Yet more issues. Multiple DTC's.

[Sinotis]

Stop wasting your time and fix the vaccum leak. This is causing all your problems. Don't change ANY other parts until your fix the vaccum leak or you will be just flushing your money down the toilet. Also the whole "its in your tune" problem is getting old to. If you had a bad plug or COP you wouldn't get a random misfire code. You would get a specific code for a specific cylinder. Random misfire and lean codes are usually (there is always an exception) a vaccum leak. Please let me know where you found the leak on the passenger side.

 

[Sinotis]

Spray some brake cleaner on the passenger side area on a cool running engine and listen for the rpms to raise. This helps locate the leak. Keep a fire extinguisher handy.

 

[white05gt]

Spraying brake cleaner isn't the smartest fucking thing to do, most brands of it will eat paint. SO if you want to give advice, don't give advice that will fuck up someones car.

 

[Sinotis]

I didn't know his engine was painted.

 

[white05gt]

It usually splatters and would get on paint in the engine compartment and could cause problems. I have some brake clean in my garage I won't use because it's so nasty. I sprayed it too close to my Snap on box and it ate into the powder coat where it splattered on it.

 

[marcspaz]

A vac leak is not caused by adding Octane Boost and other fuel additives. Dirty plugs and adaptive tuning issues are though.

Spraying brake kleen all over the engine is not only a bad idea for paint on the engine, under the hood, and exposed body panels, but it dry-rots rubber seals and hoses, wires, harnesses, plastic connectors and (as mentioned) can catch on fire and do some major damage.

There is also the fact that you will be spraying this stuff all over a runing engine. The belt, cooling fan(s), and other vented items can spray cleaner back all over the person doing the spraying, causing skin burns, damage to the eyes and other soft tissue, along with the inhalation dangers.

Sure, you might find the leak spraying that crap, but shit dude, it aint 1970. Spend $20 for a vac leak test gauge.

 

[bolted3v]

subscribing

 

[navbtcret]

Spray some carb cleaner if you want to spray anything. I have used it many times over the years looking for small vaccum leaks.

 

[Tom]

Well I fixed my promblem.. Me and Tony G from Tuners inc( Hurricane and Tuners inc share the facility) had to go to a local mustang this evening, so we datalogged the whole time, and ended up retuning the car 3 times. It was running way to rich causing the issue, Running rich will not always cuase these promblems, but the fuel trims were off, so we corrected the timing and the fuel tables. At WOT it has always been on point, but the drivability aspects were way off. The cold weather completely changed everything.

Im not implying that the OP doenst have a vac leak, or bad sensors, but if the sensors were bad the car would stay in open loop and it would really act funny. Even though his car seems to be acting funny anyway lol

 

[Miracle]

Ok... here's my assumption.

The O2's are fucked up.

All the plugs have been replaced with Autolite HT0 sparklers, and it still has a SLIGHT, SLIGHT "misfire" of sorts. It still hesitates and stumbles at anything over just a LITTLE bit of throttle. So going to try some new O2's, and hopefully that cleans her up enough to fix the problem.

 

[marcspaz]

Sorry to hear that man. I was hoping that cleaning them would do the trick. Did it show any signs of improvement with the cleaning?

 

[Miracle]

Sorry to hear that man. I was hoping that cleaning them would do the trick. Did it show any signs of improvement with the cleaning?

Minimally.

It's fine and smooth as hell, up until you try to get on it any. Cruising is smoother than it's ever been though, with that minor misfire issue I fixed with the replacement HT0's.

COULD it be a vacuum leak? That guy from earlier has me thinking now... or do we know for SURE it's the O2's?

 

[marcspaz]

I don't know anything for sure, as I have not been able to put my hands on the car. I am taking an educated guess and making recommendations based on how these cars work vs what you told my you are experiancing.

Now, with that being said... it is extremely unlikely you have a vac leak as your primay issue. Changing plugs would have made zero change. Is it possible that there is some vac leak... absolutely. A $20 gauge can help tell you that. If you want to test it, it is very easy. I can also tell you the common leak points to check...

A Mass Airflow Sensor being unpluged or bad could also cause this issue. An air intake leak too. There are many things that cause these types of symptoms.

Along with testing vac, you can get some MAF and TB cleaner and clean you intake assembley before you spend $90 on o2 sensors. If you know anyone with a good running s197 that you can swap MAFs with for testing, that is an option too. All of these are valid tests and it will give you some peice of mind.

Before this started, did you ore anyone else work under the hood?

 

[Miracle]

Before this started, did you ore anyone else work under the hood?

Nope.

And my boost gauge does not flutter at all, given any condition of throttle input. It always holds steady at right about 18-19 in/hg at idle.

I had always had a slight misfire issue with the Brisk plugs, but since replacing the plugs with HT0's, I THINK it may have gone away. (Spark blowout, perhaps?)

But no, prior to this issue, no work was done to the car/intake/manifold systems at all. Only thing I did out of the ordinary was add some STP octane booster, and the Redline fuel system cleaner, trying to clear up that damned misfire. And then THIS problem started about a half a tank of fuel later, after the octane booster.

 

[marcspaz]

Nope.

And my boost gauge does not flutter at all, given any condition of throttle input. It always holds steady at right about 18-19 in/hg at idle.

I had always had a slight misfire issue with the Brisk plugs, but since replacing the plugs with HT0's, I THINK it may have gone away. (Spark blowout, perhaps?)

But no, prior to this issue, no work was done to the car/intake/manifold systems at all. Only thing I did out of the ordinary was add some STP octane booster, and the Redline fuel system cleaner, trying to clear up that damned misfire. And then THIS problem started about a half a tank of fuel later, after the octane booster.

Ah, cool... you have a Vac/Boost gauge and the vac levels sound right on the money. That's great news. I am assuming that while in boost there is no noticable changes either?

I am not a fan of Brisk. On any car I have ever owned, I have always used NGK, Autolite, or Motorcraft. I always have problems with other brands, regardless of the vehicle.

I am glad this turned out to be a simple (affordable) fix.

Now that everything is swapped out and you have good gas, etc., I would still clean the MAF and TB. After that, clear the short term fuel trims again and follow the reset process. Those few things may take the last little bit of lag/chatter out of it.

IIRC, once the engine is at normal temps, re-flash the car with your hand held, but before you start it after the flash, you pull the battery cable for 10 - 15 minutes (if the alarm horn beeps when you hook it back up, then you know enough time went by).

Hook the battery up, start the car, and without touching the gas or brake, let is idle for 60 seconds with the AC off. Then let it idle for 60 seconds with the AC on. Then go for a ride for about 10 minutes driving causually. Once you shut off the car and restart it, the clearing and retuning process is complete.

 

[Sinotis]

So after cleaning the MAF didn't work did you finally find the vaccum leak?

 

[bullitt boy]

Just a stupid question ,when was the last time you changed your fuel filter?Car idles fine but under load loses power, load = fuel demand change your filter before tearing the thing apart.

 

[Miracle]

Just a stupid question ,when was the last time you changed your fuel filter?Car idles fine but under load loses power, load = fuel demand change your filter before tearing the thing apart.

Hmmm... good question. It HAS been a while... about 20,000 miles or so since I changed it. May look into that before the O2 gets replaced.

So after cleaning the MAF didn't work did you finally find the vaccum leak?

I can pretty much promise you that it isn't a vacuum leak man. Due to the fact that vacuum holds steady at idle, and doesn't surge or drop off at all, and also due to the fact that it's only at application of any throttle do I get any change of the car's behavior.

 

[marcspaz]

Just a stupid question ,when was the last time you changed your fuel filter?Car idles fine but under load loses power, load = fuel demand change your filter before tearing the thing apart.

Good idea... If he has a paper filter it might be ok, but the plastic ones melt a little and get glogged after adding some types of fuel system cleaners. Even with 20k on it, he may want to change it anyway.

So after cleaning the MAF didn't work did you finally find the vaccum leak?

LOL...

 

[white05gt]

That guy won't give up on the vacuum leak theory lol