2007 Ford Mustang GT 4.6 V8 3v running lean

[Beerus]

hello i hope someone could help me and give me an idea where to look to sort my problem out as im at a loss and many others have tried to fix it but have no clue, big lengthy post incoming,

so basically i had an engine swap last year in October as my last engine was completely destroyed, passenger side cams completely destroyed, no oil delivery on that side etc it was a wreck and suggested for a new engine by these mustang specialists i took it to, my last engine ran lean but never had loss of power or anything, this new engine i had rebuilt from timing components to brand new OEM cams with uprated rollers etc to prevent having this problem ever happening again, so i got the car back, its has loss of power under heavy load, so it sputters and holds back from 0 to 60 but after 60 it seems to burst to life and stop sputtering and goes as it should, i took it back to the specialists 3 times for this issue only for them to take my money and no improvements at all, i am a experienced mechanic but when it comes to this car there is not alot of info on these in the UK so its hard to find parts and any info on these cars, this is why i took it to a garage that specialises in these cars, but they have no clue and pretty much guessing really and i seem to be wasting my money, there last suggestion was replace the wiring loom as mine is in poor condition but to get it replaced by them was alot of money so i walked away from that as that will be my last resort if anything below doesn't work,


from the way the car is acting its not getting the fuel it needs so i looked into fuel delivery, when looking at my fuel trims short and long, my long fuel trims are maxed out at 25% they do not move at all at idle, my fuel trims on both banks was between 10% to 16% but bank 1 was around 6% to 8% so bank 2 seems to be more leaner in general and that was at idle, the fuel gauge also randomly at 72 miles or 46 miles it drops to 0 and says there isn't any fuel it in and acts there isn't any fuel in the tank, i even got a fault code of B2879 Fuel Tank JET Pump Error which someone said my transfer pump has failed, i took the top off on the passenger side and the fuel pump side and i had a full tank of fuel on the passenger but the drivers side was almost empty, so i replaced the transfer pump with a new one, filled it up and tested it, no different in the fuel trims still runs lean and the gauge STILL drops to 0 at 72 miles or 46 miles and acts like there is no fuel, i replaced the fuel pump and fuel filter, no different still does the same thing, sputters under load, fuel trims no different and fuel gauge to 0 when i hit 72 miles left or 46, replaced the fuel pressure sensor after getting a fault code P0193 Fuel Rail Pressure sensor High Input which that code hasn't come back since, but made no difference for my issue, so i started to look at injectors, i got brand new stock injectors but i also bought some uprated injectors of 24lb from last year, so i swapped injectors thinking it could be injectors, made no difference had slight improvement on bank 2 short trims but nothing major, so i swapped them back to stock as no point using the 24lb injectors,


so i started focusing on the air side of things, i did have an IMRC error saying my runners on bank 2 was stuck open, so i took off the intake manifold and cleaned them up and made sure the motor was working as well and it appears to be working fine, i put it all back together, not had that fault come back since but still made no difference to my fuel trims and lean issue etc, i tested purge valve which was fine after i had a fault code P0443 Purge Valve Circuit Malfunction so no clue what that was about but it hasn't come back since (its the valve on top of the engine right side near air filter not sure if that was the valve it was talking about), i bought a brand new OEM maf sensor and replaced that, made no difference (my car does have a ford performance cold intake filter on but it shouldn't effect my car this bad and came with the car originally when i bought it), so i borrowed a smoke tester and looked for any air leaks, low and behold the throttle body is leaking badly, i do have a spacer on between the throttle body and intake manifold but it was leaking bad, so i took it off cleaned it all up and resealed it and tested it, and my short fuel trims improved alot on idle, bank 1 -0.8 to 0.8, which is normal i believe and bank 2 however between 4% to 8% which is still bad so compared to how it was which was 10% to 16% is big improvement but still lean, so i did some readings driving it, and both banks was jumped to 16% to 21%, if you moderately accelerate the long fuel trims do drop to 4.6% so its improved them as well but still maxed out at 25% on idle and driving normally, so its still running pretty lean, so i did a smoke test again and its still slightly leaking from the throttle body but not from the same places as it was but from the sensor side (left) and it was also leaking from the breather pipe that connect to the inlet pipe ( i have a plastic inlet pipe as my rubber pipe spilt in the past) so i tightened the clips to seal them and that's stopped leaking, so i'm going to replace the throttle body next month with a brand new OEM one to rule all that out and going to remove the spacer as well because really it doesn't really do alot at all if barely anything so i can rule that all out, but i have i feeling this isn't going to fix my lean issue and think it might be something else but its a start,


and odd one but not sure if its related to any of this, but my battery gauge works when it wants to n says low input and high input then does a full circle then works normal then doesn't work at all which is the majority of the time now, it used to work perfect till the engine swap was done, so im not sure if there is a ground issue somewhere or causing the car to be lean i don't know, or maybe my stepper motor is gone i don't know, but thought might be worth mentioning that one but i tested alternator for precaution and its charging normal so no idea what that's about or if its related


i am at a loss here and don't know what else i can try to fix this issue, i was going to go down each list to replace everything related from brand new o2 sensors to doing an IMRC delete to rule all that out as i know its common problem for them to fail and get it tuned, new sparks and coils etc, just going down the line what might effect it but its all seems to be guess work with this car right now,


if anyone has any ideas or where to start or knows the problem i really appreciate your help to get this sorted once and for all and so i can start driving it again as it was my daily till all this happened if you can send pictures or videos what to look at or what to replace or try if its the problem would be a massive help for me too!

many thanks

Beerus

 

[bambam 06]

Your first mistake was to take it to "mustang specialists" Claimed by who? You live in UK, i don't know how the law works there against scammers, but i would try to recoup your money and try somebody else.

 

[Beerus]

Your first mistake was to take it to "mustang specialists" Claimed by who? You live in UK, i don't know how the law works there against scammers, but i would try to recoup your money and try somebody else.

well they are very known in the UK and was highly recommended and regarded as specialists in the mustang/muscle car scene here, and nothing i can do about getting my money back in regards of trying to fix this issue as they could argue it was time spent on the car etc, but it is what it is with the money spent and not going to chase the money back, unfortunately there is no one around here willing to look at these type of cars really, not even normal garages would look at this car they would turn you away in seconds because they have no clue on them, they will tell you to take it to specialist or ford dealership which not even ford want to look at it because its too old to them and have no knowledge or parts to get to repair them, its pretty lame here, i just want my car working as it should and not cost me another engine down the line =/


me posting this here was my only and last hope

 

[Dino Dino Bambino]

@Beerus welcome to the forum.
You've run into the same problem that all of we European Stangers have. Since the S197 platform was never sold in any European dealerships and all of them were personally imported LHD vehicles, mechanics know nothing about them and many won't touch them. Even the so-called Mustang specialists are only familiar with older vintage Mustangs, but they should surely at least be able to work on the S197 suspension, steering, braking systems, and drivetrain since they aren't rocket science.

Therefore you'd better arm yourself with as much knowledge as possible about these cars and find trusted parts sources in the US. We can guide you with a few tips. Believe it or not it's cheaper to buy new parts in the US and ship them yourself than buying in the UK. You might be lucky enough to live not far from a scrapyard that has some used parts if they happen to be breaking an S197. I'm lucky enough to have a trusty local mechanic in Cyprus who does good work on my car and I supply him with the parts. My advice is to buy multiple parts in the same order to minimise shipping costs.

You definitely need to have your own ECU code scanner, and I'd highly recommend you buy an ELM 327 Bluetooth OBD 2 (I have the Total Diagnostics version) scanner that plugs into your under dash diagnostic port. If you download the Car Scanner app onto your smartphone and pair it to the scanner, you'll be able to monitor live data, record it, and save the files. You can also create your own custom dashboard with gauges of your choice. Pretty cool stuff.

Let us know if replacing the throttle body fixes the lean issue. As for the throttle body spacer, it's a waste of space (pun intended) whose main purpose is to lighten your wallet, though it's anodised finish does make it pretty enough to use as a paperweight!

 

[Beerus]

@Beerus welcome to the forum.
You've run into the same problem that all of we European Stangers have. Since the S197 platform was never sold in any European dealerships and all of them were personally imported LHD vehicles, mechanics know nothing about them and many won't touch them. Even the so-called Mustang specialists are only familiar with older vintage Mustangs, but they should surely at least be able to work on the S197 suspension, steering, braking systems, and drivetrain since they aren't rocket science.

Therefore you'd better arm yourself with as much knowledge as possible about these cars and find trusted parts sources in the US. We can guide you with a few tips. Believe it or not it's cheaper to buy new parts in the US and ship them yourself than buying in the UK. You might be lucky enough to live not far from a scrapyard that has some used parts if they happen to be breaking an S197. I'm lucky enough to have a trusty local mechanic in Cyprus who does good work on my car and I supply him with the parts. My advice is to buy multiple parts in the same order to minimise shipping costs.

You definitely need to have your own ECU code scanner, and I'd highly recommend you buy an ELM 327 Bluetooth OBD 2 (I have the Total Diagnostics version) scanner that plugs into your under dash diagnostic port. If you download the Car Scanner app onto your smartphone and pair it to the scanner, you'll be able to monitor live data, record it, and save the files. You can also create your own custom dashboard with gauges of your choice. Pretty cool stuff.

Let us know if replacing the throttle body fixes the lean issue. As for the throttle body spacer, it's a waste of space (pun intended) whose main purpose is to lighten your wallet, though it's anodised finish does make it pretty enough to use as a paperweight!

i appreciate the wise words, i do have an OBD 2 scanner i paid abit of money for that reads and takes data from the car, but not like the one you have. ill have to invest because i need to find this issue, i tested the lines in the tank today and they seem clear and not leaking so my fuel lines in a tank is ruled out,

yeah i bought that spacer to try out last year and it doesn't do really anything but a extremely slight throttle response but im going to take it off when i get my new throttle body, its pointless to have really, i will keep this thread updated,

in the mean time if anyone else has any other ideas to try or know what is causing this issue please let me know! thank you!

 

[Autokyrios]

Like Dino said, it'll be hard to find someone who's experienced with the 3v, and parts can be tricky. Getting Ford parts isn't usually that bad, as even if the dealerships don't know it, they're able to get on the parts network and order if you know what you need. Other places ship global (like RockAuto, Summit...Jegs will if you call them first). Who knows in today's whacko.

As for the problem, like Dino said, being able to datalog will be helpful.

The purge valve (what you mentioned) needs to function, as does the emissions kit under the trunk. If either of those are disconnected, codes will throw. I had mine not start once because I forgot to reconnect the kit in the back.

New fuel pump, driver and filter so that should be fine. If you have access to a fuel pressure gauge you can put on the line, you can see if it's actually doing anything. You'd probably hear it if it wasn't, though. It makes a good sound on fresh startup.

You mentioned your harness was in bad shape, and you're having a whole bank fail. Have you traced the wires to see if there's a fault? Replacement harnesses are incredibly expensive, but before going that route I'd crack open your loom and hunt through it. Everything's fairly straightforward as far as runs.

I unfortunately no longer have contact with two friends over there who had S197's but I remember one was affiliated with a local mustang club and the other was doing parts testing with Vortech or Roush or something like that (always seemed to have new parts he was testing).

 

[Beerus]

Like Dino said, it'll be hard to find someone who's experienced with the 3v, and parts can be tricky. Getting Ford parts isn't usually that bad, as even if the dealerships don't know it, they're able to get on the parts network and order if you know what you need. Other places ship global (like RockAuto, Summit...Jegs will if you call them first). Who knows in today's whacko.

As for the problem, like Dino said, being able to datalog will be helpful.

The purge valve (what you mentioned) needs to function, as does the emissions kit under the trunk. If either of those are disconnected, codes will throw. I had mine not start once because I forgot to reconnect the kit in the back.

New fuel pump, driver and filter so that should be fine. If you have access to a fuel pressure gauge you can put on the line, you can see if it's actually doing anything. You'd probably hear it if it wasn't, though. It makes a good sound on fresh startup.

You mentioned your harness was in bad shape, and you're having a whole bank fail. Have you traced the wires to see if there's a fault? Replacement harnesses are incredibly expensive, but before going that route I'd crack open your loom and hunt through it. Everything's fairly straightforward as far as runs.

I unfortunately no longer have contact with two friends over there who had S197's but I remember one was affiliated with a local mustang club and the other was doing parts testing with Vortech or Roush or something like that (always seemed to have new parts he was testing).

would the purge valve or emissions kit under the trunk cause any lean problems and cause any power loss under load???


got no pressure gauge but ill see if i can borrow one if not buy one and try it,

yeah he harness isn't in the best condition and it has repairs in places what the last owner did, i have been tracing wires in the past but everything seems ok, but with the new engine i haven't checked so it might be worth looking again, especially the ground wires as my battery gauge isnt working properly at all i have a feeling they haven't grounded it properly some where =/

i appreciate the reply and the insight, i will start checking some wires tomorrow n see if i can find anything

 

[Juice]

Is the car actually throwing bank lean code? And how long does it take for the code to set?
I ask, because the description sounds very familiar (way lean idle) to an issue I had that was a small vacuum leak.(intake to head)

 

[JC SSP]

If you think there a vacuum leak, then a spray bottle with soapy water might work. If not, then try a smoke tester, that will definitely show where a leak is.

 

[Autokyrios]

would the purge valve or emissions kit under the trunk cause any lean problems and cause any power loss under load???

Emissions kit (under the trunk) really only takes in excess vapors. It only causes an issue if the computer can't sense it (I think it's tied to one of the readiness checks). They CAN get clogged or fail (my original had a failing switch and I replaced after about 2 years) but it's not common. I don't know of any service-period information for them.

The purge valve in the engine bay will cause problems if it goes bad or is disconnected. It's involved in the engine vacuum/pressure setup and if it's bad it can essentially be a plug. They're fairly easy to check. Just disconnect it from the tubes and electrical connector and give it a little shake. If it rattles, it's bad. If you haven't changed yours before, it's worthwhile to just get a new one and be safe.

On the lean side of the argument, the engine ECU by default tends to go rich when it encounters a problem its aware of, since being fuel-rich is better than starved.

 

[Beerus]

Is the car actually throwing bank lean code? And how long does it take for the code to set?
I ask, because the description sounds very familiar (way lean idle) to an issue I had that was a small vacuum leak.(intake to head)

Yes i have a both lean codes for bank 1 and 2, i had this on the previous engine but it wasn't so bad that it took away power from me you see, but this time on the new engine its so big its taking power away, but i did do some live testing for last couple of days.

 

[Beerus]

I have being doing some tests as i bought one of them OBD 2 dongles that dino recommended and i bought an app to do some tests while driving, while driving the long fuel trims do go down if you give it abit of heavy acceleration, short fuel trims can be all over the place, but i switched it to the boost gauge on the app and it confirms thats there is a vac leak some where, n i never noticed this before but when you floor it you can hear something sucking in under load, so after the tests i have done i defiantly got a vac leak, my boost on normal driving is -9.6 to - 6.0. but then when you boot it, it drums to +4.4 confirming its sucking in air from somewhere, so i know the throttle body isnt right so will replace that in next 3 weeks and will post an update, i appreciate everyone's help and suggestions and we are slowly winning,

as i said before any more suggestions what it could be please lay them on and ill check them out thank you all so much

 

[Beerus]

Emissions kit (under the trunk) really only takes in excess vapors. It only causes an issue if the computer can't sense it (I think it's tied to one of the readiness checks). They CAN get clogged or fail (my original had a failing switch and I replaced after about 2 years) but it's not common. I don't know of any service-period information for them.

The purge valve in the engine bay will cause problems if it goes bad or is disconnected. It's involved in the engine vacuum/pressure setup and if it's bad it can essentially be a plug. They're fairly easy to check. Just disconnect it from the tubes and electrical connector and give it a little shake. If it rattles, it's bad. If you haven't changed yours before, it's worthwhile to just get a new one and be safe.

On the lean side of the argument, the engine ECU by default tends to go rich when it encounters a problem its aware of, since being fuel-rich is better than starved.

thank you for this info, ill will swap it anyway for safety and to rule it out

 

[Juice]

Loss of power, hmmmm, cat converters clogging up? Bad converters can also cause system lean codes.

 

[Beerus]

Loss of power, hmmmm, cat converters clogging up? Bad converters can also cause system lean codes.

the loss of power only happens on full throttle, so it sputters like its choking or not getting enough fuel, but i will be decatting the car this year, but im going to buy new o2 sensors to also rule that out too.

 

[Dino Dino Bambino]

but i will be decatting the car this year

Won't that be an instant MOT failure in the UK? BTW if your cats were going bad, they'd trigger cat efficiency codes in the ECU and since you don't have those, there's no need to go down that rabbit hole just yet. New O2 sensors probably aren't a bad idea since the originals are old enough to vote now. Only buy NTK branded sensors. Don't buy Bosch as these have been problematic on some cars.
Replace the throttle body first and go from there.

I have being doing some tests as i bought one of them OBD 2 dongles that dino recommended and i bought an app to do some tests while driving,

If that helps you fix the problem, you can buy be a beer next time I'm in the UK.
The evap charcoal canister shouldn't clog up unless you overfill the tank with fuel. You could try removing the assembly from under the spare wheel well and blowing compressed air through it. If air comes out of the other side you know it's good. Unfortunately you can't buy a new assembly because Ford has discontinued them.
It's recommended to stop filling as soon as the fuel nozzle does its first click. However many of us get that as soon as the tank is only half full because the fuel filler neck on models built before May 2008 doesn't have a vent tube (stupid design) to release trapped vapours.

 

[Beerus]

Won't that be an instant MOT failure in the UK? BTW if your cats were going bad, they'd trigger cat efficiency codes in the ECU and since you don't have those, there's no need to go down that rabbit hole just yet. New O2 sensors probably aren't a bad idea since the originals are old enough to vote now. Only buy NTK branded sensors. Don't buy Bosch as these have been problematic on some cars.
Replace the throttle body first and go from there.

If that helps you fix the problem, you can buy be a beer next time I'm in the UK.
The evap charcoal canister shouldn't clog up unless you overfill the tank with fuel. You could try removing the assembly from under the spare wheel well and blowing compressed air through it. If air comes out of the other side you know it's good. Unfortunately you can't buy a new assembly because Ford has discontinued them.
It's recommended to stop filling as soon as the fuel nozzle does its first click. However many of us get that as soon as the tank is only half full because the fuel filler neck on models built before May 2008 doesn't have a vent tube (stupid design) to release trapped vapours.

Cats are required for an MOT in the UK yes but there are ways around it, as long as a car passes an MOT there is literally nothing anyone can do about it as its passed as road legal, as long as the emission don't go over a certain point how can they argue? but millions of people in the UK have them cut out anyway and no body is assed over them, not even the police unless its a jobs worth,

i have always been told to always go for the OEM parts if possible and luckly i can get some motorcraft o2 sensors new on rock auto so that will be my mission, if all this works ill buy crates of beer mate haha,

this car has been a a nightmare since my gearbox blew up (completely different story) and following my engine just after, but i can't just take the loss on it as i love this car too much, its definitely a mystery car and something special about it, not alot of info about this car, all i know about it was made in Michigan was taken to Dubai which apparently a prince owned (personally think the guy who sold it to me was talking crap abit on that one) n it came to the UK wasn't used because it was breaking down every 10 miles ( was an ECU wire corroded) and i bought it n sorted it out n it was great for the first year, had it dyno tested because it was faster then a stock 4.6 3v around here, had 380bhp at the crank and 323whp with 360ft lbs of torque, but don't know why it did what it did, but with the new engine i don't know if it will be the same or not or if its a map on the car, but either way its best car i have ever had till all problems stated above, n now i just trying to get it restored and sorted out as i miss driving it as it is my daily,

when i refuel it cuts out on half all the time and i did fix it with a sensor under the car near the fuel tank but its started cutting out again at half, i always thought maybe getting these canisters cut out would work but if its actually the nozzle thats the issue i might have to find a way to get the vapors out to prevent this issue.

 

[Dino Dino Bambino]

Cats are required for an MOT in the UK yes but there are ways around it, as long as a car passes an MOT there is literally nothing anyone can do about it as its passed as road legal, as long as the emission don't go over a certain point how can they argue? but millions of people in the UK have them cut out anyway and no body is assed over them, not even the police unless its a jobs worth,

Criminals have made a big business out of crawling under people's cars and stealing the cats for their precious metals so I guess owners have given up in frustration and decided to do a permanent cat delete.

not a lot of info about this car, all i know about it was made in Michigan was taken to Dubai which apparently a prince owned (personally think the guy who sold it to me was talking crap a bit on that one) n it came to the UK wasn't used because it was breaking down every 10 miles ( was an ECU wire corroded) and i bought it n sorted it out n it was great for the first year, had it dyno tested because it was faster then a stock 4.6 3v around here, had 380bhp at the crank and 323whp with 360ft lbs of torque, but don't know why it did what it did, but with the new engine i don't know if it will be the same or not or if its a map on the car

The part about a prince owning it is definitely BS. In Dubai princes drive Ferraris, Lambos, or AMG Mercedes G Wagens. The more likely story is that the car was accident damaged in Michigan, written off, sold in a Copart auction, exported to Dubai where the car was repaired in a backyard workshop, and then put back on the road. All the problems you've had with the car are probably a legacy of that previous accident. It probably sat for a few months as well in salty sea air before it was even repaired.

had it dyno tested because it was faster then a stock 4.6 3v around here, had 380bhp at the crank and 323whp with 360ft lbs of torque,

Those are impressive dyno numbers, and 360rwtq is higher than anything I've ever seen from an N/A 4.6. The dyno operator evidently divided 323rwhp by 0.85 to arrive at a rather optimistic 380 crank horsepower, given that the "industry standard" 15% drivetrain loss for manuals dates back to the 1960s when drivetrains were less efficient. A figure of 12% (divide rwhp by 0.88) is far more representative, making yours 367 crank HP.
You didn't mention any mods apart from.an ECU remap but things like a CAI, headers, aftermarket exhaust, and shiny underdrive pulleys will be very obvious. Charge motion delete plates won't be unless you look on the back of the engine and see the CMCV actuators either disconnected or missing, and Steeda underdrive pulleys are black so they look too subtle to the untrained eye.

when i refuel it cuts out on half all the time and i did fix it with a sensor under the car near the fuel tank but its started cutting out again at half, i always thought maybe getting these canisters cut out would work but if its actually the nozzle that's the issue i might have to find a way to get the vapors out to prevent this issue.

There isn't anything you can do unless you jack up the rear end. I just trickle the fuel in slowly once the tank gets past half full and it's a pain in the backside that I've learnt to live with. Rotating the nozzle in different directions doesn't make any difference.

 

[Beerus]

Criminals have made a big business out of crawling under people's cars and stealing the cats for their precious metals so I guess owners have given up in frustration and decided to do a permanent cat delete.


The part about a prince owning it is definitely BS. In Dubai princes drive Ferraris, Lambos, or AMG Mercedes G Wagens. The more likely story is that the car was accident damaged in Michigan, written off, sold in a Copart auction, exported to Dubai where the car was repaired in a backyard workshop, and then put back on the road. All the problems you've had with the car are probably a legacy of that previous accident. It probably sat for a few months as well in salty sea air before it was even repaired.



Those are impressive dyno numbers, and 360rwtq is higher than anything I've ever seen from an N/A 4.6. The dyno operator evidently divided 323rwhp by 0.85 to arrive at a rather optimistic 380 crank horsepower, given that the "industry standard" 15% drivetrain loss for manuals dates back to the 1960s when drivetrains were less efficient. A figure of 12% (divide rwhp by 0.88) is far more representative, making yours 367 crank HP.
You didn't mention any mods apart from.an ECU remap but things like a CAI, headers, aftermarket exhaust, and shiny underdrive pulleys will be very obvious. Charge motion delete plates won't be unless you look on the back of the engine and see the CMCV actuators either disconnected or missing, and Steeda underdrive pulleys are black so they look too subtle to the untrained eye.


There isn't anything you can do unless you jack up the rear end. I just trickle the fuel in slowly once the tank gets past half full and it's a pain in the backside that I've learnt to live with. Rotating the nozzle in different directions doesn't make any difference.

Very true, its very common in UK to get your cats nicked, especially in my area,

and you are correct on the car being in an accident, but we didn't know about it till we was getting it through painting you see, looks like it had a front end smack with a lorry, but here a kicker for you, the guy who bought it in the UK bought it broken, bodged it to be road legal, only did 2000 miles in 4 years then sold it to me, when we took off the front bumper i was shocked because the front bumper was reinforced with wood.....no joke, even got a picture will leave below, if i ever got into an accident, that engine would be in the cabbin with us....couldn't believe it,

yes it shocked me as well because i thought stock had 300bhp with 300 - 320ft-lbs of torque, but this one doesn't and its a total mystery, i have not added any mods personally besides fix the engines issues which improved its power over time and i only uprated the radiator with a Mishimoto but this was the old engine, only mods i could see was an cold intake kit installed, but i can't see anything n there is no history on this car with engine mods not with what the old guys had done to it previously anyway, but its a total mystery, ill post the dyno sheet as well because it baffles me this car, the guy said it was around 380 at the crank n i did ask for a sheet on that but i never got one so i had to take his word for it but 360bhp seems more accurate to me, but only thing i could think of that maybe the car was mapped, and the ECU is from a 2008 mustang as they must of replaced it thinking the ECU was dodgy in the past when it was breaking down, but its a mystery,

i have had a 0 to 60 in 4.8 seconds in this and a 1/4 time in 13.0 and the speed at 109mph n thats when engine was on the way out, if i sort this new engine out i think it could be abit better as the people at the garage have transfer abit of parts from the old engine as well as replaced major parts with new, they seem to think it would be faster despite the lean issue and loss of power.

 

[Dino Dino Bambino]

yes it shocked me as well because i thought stock had 300bhp with 320ft-lbs of torque
View attachment 105193

Yeah, stock '05-'09 GT engines were rated at 300hp & 320lbft at the crank but I reckon the '06+ versions made a little more since the hydrocarbon trap inside the airbox lid was deleted in late '05.
Your torque curve below 3200rpm doesn't look right since it starts higher from 1800rpm when it should be lower. A true torque peak of ~303rwtq at 4500-4600rpm makes a lot more sense and since the HP number is higher, this makes me wonder if the engine has aftermarket camshafts (the popular Hot Rod cams maybe?). Perhaps that's why the ECU was remapped.

The front bumper reinforcement was certainly bodged up but it shouldn't be too difficult to put right. Once you get rid of all that surface rust and repaint everything, it'll look a ton better.

Your coolant expansion reservoir looks a nasty rusty colour. I wonder if a previous owner might have put tap water into the cooling system or used the wrong coolant. Ford recommends Motorcraft Gold concentrate with deionised water. If you can't find it in the UK, any green coolant that's compatible with aluminium engines will do fine. Never use tap water 'cause the limescale will clog up the radiator and the cooling passages inside the heads/block, eventually resulting in a blown head gasket. Remember the Triumph Stag 3.0L V8 engines that were renowned for this?