Driving me F#@*&! nuts

Hawgman

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Well, the car has decided to be a pain in my ass. As you (may or may not) know, my boost bypass valve was bad. FINALLY got through to Saleen and purchased a new one, it arrived earlier in the week. While replceing the bypass valve, I also replaced my belt. Even though it only had about 7k miles on it, it was starting to become a little stretched.

Since the replacement the car has been acting pretty odd. Symptoms are not as bad when at full operating tempature as they are when cold, but still exist.

On a normal takeoff, like neighborhood driving for example, the a/f jumps off the damn gauge. Goes up to around 17.5 according to the WBC gauge. No power, loud air sucking noise through the intake ( sounds like a smallblock with no air cleaner! ). Does this up to about 2200rpm, then runs fine. If I take off "spirited", the a/f doesn't jump as badly but still jumps to about 15.5 ~ 16. Although it does seem to run better. Running around 2500rpm in 2nd gear and floor it, a/f acts normal. Goes down to around 11. Power seems fine.

Two days ago, drove it for about 10 minutes, parked for about 15 minutes, got back in and drove. It didn't have the odd a/f readings or loss of power on takeoff. So I decided to romp on it from about a 20mph roll in 1st. It had plenty of power, got a little squirley getting in to 2nd, I stayed in it up to about 6000rpm, then shifted to 3rd and let it settle down. Looked at the dash and had a CEL. Got to where I was going and pulled the DTC and it was a P0170 ( fuel trim ). Damn... So I start poking around and trying things that I already had parts laying around to try. Replaced the fuel filter, pulled tht GT fuel pump and put the stock pump back in. Still same running symptoms. Nothing changed.

This morning I drove it around the neighborhood to do a little datalogging ( don't know why... it doesn't mean squat to me! ), parked for about 20 minutes, then headed to work. About 2 minutes in to the drive to work it threw a CEL. Pulled over and checked the DTCs, they were P0172 and P0175. Bank 1 and 2 too rich. Screwed up thing is, the WBC said it was lean. Was again around 17.5 when I pulled off from the stop, and was at 15ish when the CEL flashed up.

WTF?!?!
 

thump_rrr

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I'm grasping at straws here Doc but...

I would first concentrate on the boost bypass valve and anything you may have touched to access it. Is the vac hose snug? Does it function smoothly?

The other thing may be what was touched to replace the belt.
Did anything get on the maf by any chance?
Is there a loose vac hose?
Is the maf plugged in firmly?

I would pull the WBC sensor and re calibrate it in free air also.
 

Hawgman

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Vaccuum lines to the bypass valve are good. Valve seems to be working normally. Kind of hard to actually tell since I would have to be running beside the car with the hood open to watch it :) But it does at least come up off the stop when the car starts, and you hear it hit the stop when you shut the car off.

As for anything touched during the belt replacement. All I did was remove the intake tube. Did not unplug the MAS, or move the air filter/MAF/heatshield.
 

DirtyDogOfTheDesert

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I would try reloading your tune. Your adaptive learning may have altered things slightly to compinsate for the other valve not working correctly. Like for example if you did have a vacuum leak, computer would have added fuel. Now the leak is gone, but fuel is still being added.

I may be way off, but it's worth a try.
 

Hawgman

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I completely agree, well worth the try. And have done that. Didn't make any difference.
 

SoundGuyDave

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I'm going to agree with Thump here, my bet would be on the saleen bypass valve. What you are describing sure as hell sounds like an air leak after the MAF. The computer sees "X" amount of air coming in, which means "Y" amount of fuel, but if some of your air is taken out of the equation, you'll be running rich. The big tipoff is that all of yor codes were for fuel-related events, particularly the "rich on both banks" problem. While the MAF could be fouled, I would doubt it as the drivability returns when up to temp. I would look first at the bypass valve and see if you have an air leak there. Did you have to pull the blower body to replace the valve? If so, you may have a touch of debris in the gasket mating surface that allows leakage cold, but seals up a bit under heat...
 

Hawgman

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Bypass valve is external to the blower. Did not have to remove anything other than the two bolts that held it in place and the bolt on the butterfly actuator arm.
 

Hawgman

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Yea... didn't think of that.

The valve is working. Like I said, start the car, the arm pulls up off the stop. Turn the car off, the arm goes back down on to the rest. Which is a hell of a lot more than it was doing with the bad valve. The diaphram was completely separated from the housing in the old valve. Actuator arm wouldn't budge. BUT.. except for a rough idle and a little hesitation the car ran fine with the bad valve. Just that it wouldn't build but a couple of pounds of boost.
 

MikeVistaBlue06

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Doc,

I betca got a vacuum leak. Take a can of WD40 and squirt it around fittings and stuff until you hear the engine respond.

Also be sure your CAI hasn't cracked or is loose letting air in that the MAF doesn't sense.

Also, check to be sure an o-ring or gasket didn't slip or roll on it.

Hell gimme a holler tomorrow and we'll take a look at her. A 2nd set of eyes might do the trick!

Let me know.

Mike
 
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Hawgman

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Well, here's todays update.
MikeVistaBlue06 and I went up to HPP today to see what might be going on. Pretty much wasted an entire day today up at the shop waiting on a diesel truck dyno day to finish up so they could have someone at least look at the car. Did some datalogging and it is a complete contradiction of itself. O2 sensor voltage indicates a lean condition, yet the PCM is pulling fuel during the lean condition. This lasts for like five seconds. Then it snaps back in to normal mode. And while it was showing lean and pulling fuel, it threw a rich bank 1 DTC. Now how in the hell does the car indicate lean, still pull fuel, and throw a rich code?!?! So Manny ( owner, tuner at HPP Racing ) took my tune and adjusted it to where it went in to an open loop and we datalogged again, no change. So I am going to try to get back up there on Thursday when they have some free time and he is going to jack with it for a while to see if we can figure out what the hell is wrong.
 

Hawgman

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Peter.
If it was a stuck injector, wouldn't I see some sort of bleed down of fuel pressure when the car is not running? Meaning, turn the key on but not start the car, let full pressure build, then watch the gauge and see if pressure goes down. That should tell me if an injector is stuck open, right?

Reason I ask, is I have tried that. No pressure drop.
 

donnyonee

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im not sure about a open injector but i did have problems with a couple of mine not opening, stuck shut.
what i did was get a extra wire connector for the injectors and connect a pushbutton in series with the plug and connect it to the battery. just HIT the button, DO NOT HOLD THE BUTTON DOWN. youll burn out your inj. anyways you can hear each injector click as it opens and closes. i had a couple that after repeated hits would finally start to work and then a couple that didnt go at all. and this is because i think i got carried away with fuel octane booster and it gummed up the injectors. anybody heard of this?
(it was "pro blend" nitro power additive. i flushed the system, changed the filter and the 2 bad injectors and now on the 2nd tank of 76 premium gas, 91 oct. seems to be ok. havent tried anymore additive yet, but will in smaller amounts.)
sorry to hi jack your thread but if you think its injectors you may want to try this.
 
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Hawgman

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No hijack at all.

BTW, pretty much all off the shelf octaine booster is a no no. About the only thing that works without screwing stuff up is Torco. And even that will turn your plugs orange.
 

DirtyDogOfTheDesert

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If you had an injector stuck closed you'd have a notiable misfire. It would probably throw a code, and should be pretty easy to find it that was the case.

You could unplug your injectors 1 at a time with the car running, you should hear a noticable change every time, unless you come to a bad one.

Based on what you're saying though, I don't think this is your problem.
 

Hawgman

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Yea, I agree. Considering what the data log is showing, I would tend to think if one was stuck it would be stuck open not closed.

If I can't get it figured out soon I might be able to help Chevy Killer with him looking for a salvage title. Because I am going to torch this fucker.
 

ChevyKiller

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Come on - when you hit the 1 year mark like me, then you can get really upset...:beerdrink:
 

cekim

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Yea, I agree. Considering what the data log is showing, I would tend to think if one was stuck it would be stuck open not closed.
If I can't get it figured out soon I might be able to help Chevy Killer with him looking for a salvage title. Because I am going to torch this fucker.
No torching the stang - bad form....

Seems to me the possibilities are limited - time for some S. Holmes:

1. vacuum f'd up?
2. O2 sensors F'd up?
3. IAT sensor F'd up?
4. TCS F'd up?
5. injectors F'd up?
6. wiring between #2 through #5 and the PCM F'd up?
7. Tune F'd up?
8. PCM shit the bed... (btw - if you don't have kids or an elderly ward that phrase doesn't quite have the impact it does if you actually seen someone "shit the bed")

So, unless I missed something - Quit yer bitch'n, run 'em down and start replacing stuff Ford Service Department style until it gets better...

Have you monitored IAT and Load to see if they go nuts?

TCS stuff is new to me, but given that it does pull fuel, I'd be looking for issues there to (i.e. F'd up ABS sensor?)

Seems odd that you would have a bypass valve failure AND some other mysterious failure at the same time... Mr Occam is scratching his chin suspiciously, but can't think of why that would cause this positive fuel pulling feedback loop?

p.s. forgot about fuel pump F'd up - can't remember what your BAP/pump setup is? I presume you are watching fuel pressure and have ruled that out?
 
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