i had a hanging RPM @ 1900 all week with weather changing. only way i could get it to stop was flip the key off then back on. i tightened my exhaust and it had no change. i changed the TPS today this morning. i havent had a hanging idle afterwards or a jumping idle as i have had too. i drove it vigorously to duplicate and had no return. have you tried this?
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MadStang
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Vermilion said:
TPS is new. I'm going to work on it tomorrow, I noticed that after I run the car hard now and heat the exhaust up, I get one hell of an exhaust leak on the driver side, the cupped flange is leaking. So I've got some ultra copper gasket maker, Loctite Red, and new locking nuts from ford to resolve the problem.
As far as my electrical system goes though, if I have my music off, you can hear the alternator through the speakers, so that thing is on the way out to the trash...
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MadStang
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Vermilion said:
I'm looking to get a chrome alternator, making my engine bay shine a bit haha.
MadStang said:
My Mach picks up tons of "collapsing fields", as the electrical shop said. Then again my car took a drive into a lake.
You have tried clearing the learned memory, right? I think the battery needs to be disconnected overnight.
I'm not inclined to believe an exhaust leak is going to influence your engine to misfire, or perform in the way it does. I ran my car with the front O2's disconnected with no obvious performance hit.
Your misfire is being influenced by three things not coming together. Your fuel, your spark, or your air is causing the issue. Your ECU meters and controls the amount of fuel delivered and when it is delivered, when the spark is fired through your coils, and the amount of air flowing into the engine. ECU's can go bad, and I know at work the transmission control module is becoming an increasing cause of returns.
So we have the basis for what your engine needs, and now we can rule out controls one by one. We have generally ruled out spark, whose function is from the COP's and would generally be localized by one bad COP. I guess MAF's can go bad, but I haven't heard of it as you can assume since your car is on the surface of the planet it will be receiving air.
Finally we are left with fuel. Fuel is trickier, as it is a bigger system. The elements of your fuel system will include your fuel pump, fuel filter, the lines, the rails, the injectors, and of course the computer inputs. That's simplified, but it's roughly the right ideology. You've replaced the filter, the lines and rails are probably not clogged, you've replaced the injectors, so what's left?
Fuel pump? FPDM? I look at your datalogging sheet and ask myself WTF am I looking at. All I can say is you seem to have a fuel delivery problem at this point, and since you've replaced the injectors we're down to the last two things for this round of diagnosis. The way I look at things is that your fuel pump could be going out. With my 97 when the fuel pump was going out I could drive it for about 45 minutes and then the car would run rough and shut off when the pump failed. When the pump got hot and worked, then the failure would show up. With your vehicle, it may run fine until it warms up, when the pump will start to operate erratically and not deliver the requested fuel from the FPDM causing your car to misfire and eject the unburnt fuel, into your nostrils sometimes.
Maybe I don't know shit and it's a vacuum leak. But there's something more to think about.
Lee12609 said:
I must have missed the post where it said "the car is running perfectly now, thanks for the suggestions".
As far as I can tell from piecing together several different posts together, the car still has a crappy idle and acts erratically on acceleration. If the OP would care to update us on the performance of his engine, then I would be happy to relent upon hearing his vehicle works fine.
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MadStang
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enough guys.
The car has still be running like crap. I did have an exhaust leak pre-o2 sensor. I just took care of it with some Ultra Copper Gasket maker and some thread locker. The driver flange (the cupped flange) had a leak, so i just reinforced that there would be no issues with it by adding the gasket maker. I'm letting it dry now and will post results tomorrow when I drive to work.
If this doesn't solve the problem I'll be surprised, The hanging idle only was apparent when the exhaust leak was. Otherwise the car has been decent to drive, I've only had one close call to the car stalling, it's an off ramp by my house that requires both steering as well as braking input, and it went down to 300rpm, I noticed, gave it a little throttle and it leveled out at normal idle.
So I feel like I'm getting closer, if I don't find that the exhaust leak fix was the cause, I'll be getting another smoke test to verify if I have another leak or not.
The car has still be running like crap. I did have an exhaust leak pre-o2 sensor. I just took care of it with some Ultra Copper Gasket maker and some thread locker. The driver flange (the cupped flange) had a leak, so i just reinforced that there would be no issues with it by adding the gasket maker. I'm letting it dry now and will post results tomorrow when I drive to work.
If this doesn't solve the problem I'll be surprised, The hanging idle only was apparent when the exhaust leak was. Otherwise the car has been decent to drive, I've only had one close call to the car stalling, it's an off ramp by my house that requires both steering as well as braking input, and it went down to 300rpm, I noticed, gave it a little throttle and it leveled out at normal idle.
So I feel like I'm getting closer, if I don't find that the exhaust leak fix was the cause, I'll be getting another smoke test to verify if I have another leak or not.
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MadStang
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Vermilion said:
the main reason I noticed the leak was because of the black soot on my oil pan when I pulled the car out earlier in the week. then I listened heard the TAP TAP TAP TAP TAP. haha.
Honestly if they used the gasket like they do on the passenger side on the driver it would seat a lot better. only problem with that would be fitment with a fixed flange vs. the cupped style, so it's understandable, just gotta ensure perfection.
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MadStang
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<----- is getting frustrated. I torqued the mid pipe down, and I mean I TORQUED it down. put the gasket maker on in excess, and even put loctite on the threads. I fired it up and it was fine just idling even when I got it up to temp. took it out for a nice light drive and for most of the drive the car was PERFECT, no idle hang, no sputtering letting off the gas. then I'm a mere block away and I feel only at 2100 rpms the car sputter. pull back in and now i hear TAP TAP TAP, once again from the driver side. WTF. I did everything perfect.
I'm getting very, VERY aggravated now. I have to wait until next weekend to fix this.
I'm getting very, VERY aggravated now. I have to wait until next weekend to fix this.
Mustang Mark
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yes you mayJDwhite98gt said:
something to eat while we wait to see how it turns out.Lee12609 said:
JDwhite98gt
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What midpipe comes with the stg2?
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MadStang
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JDwhite98gt said:
h-pipe with 6 cats... I hate California...
but I'm running a Mac O/R H-pipe.
JDwhite98gt
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yea but thats right you switched to the stocker and had the same problems....so maybe the leak is not as big of an issue as u think
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MadStang
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JDwhite98gt said:
it is the issue, guaranteed. I had a vacuum leak so that made things all outta wack. I guarantee you if I put the Catted h on it would solve the rough idle, but, my alternator took a crap on me about 5 times. I heard one of the pulleys squeaking it's ass off all 5 times when the car died. Looks like imma be buying an alternator...
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MadStang
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getting a PA performance 200A Chrome Alternator. Should do the job me thinks 
