THSCC Forums

yeah fuel trims are pretty much what bret described. if you are having a fuel delevery issue like you think the engine would be running lean, even if its not bad enough to cause the cel to come on you would be able to see it in the fuel trim data.

edit

i just had another thought how old is the gas in the car? how long ago did this become an issue?

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#77 nasa spec 3
e36 M3

funny you should ask..... This has been happening for the last 2 events I've run this year. Gas is fresh, or as fresh as the last tank from a week ago, so no issues there. I actually think this has been happening for quite some time. Back in 09 when I last drove the 328 up in Danville I noticed the car was doing the exact same thing, no go when you had the pedal floored. At that time I just chalked it up to mileage and bad vanos on the car. Shortly there after I picked up the mustang and thought nothing else of it.

Since Jordan was now using the car as a DD, the issue never came back up as he just never drove it hard enough to make the lean condition return. Up at NCCAR, the car would simply die, no power what so ever after it had a few runs on it. As stated at the beginning of this thread, I replaced the fuel filter in hopes that was the issue. The old filter had never been replaced and was in fairly sad shape. That replacement unfortunately was not the fix.

I'm getting a used fuel pump from Bret in a few days and I'll play/test from there. I really hope this is the fix, I'd love to be competitive again, but right now the car is very frustrating to drive.

So this begs the question. What ODBii tester should I invest in so I can chase these issues down? I know bavauto has a new tester out that's BMW specific. Looks like a smart phone w/ a display for the codes. Much nicer than the peak reader w/ the codes and booklet.

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Rodney

'08 Bullitt mustang, CAM 7
Autox VP '09-'10, President '11-'12, interim President 2nd half of ‘14
proud recipient of the Bowie Grey service award '12
Now just a guy driving a mustang....

well damn i thought might be onto something, i'll keep thinking.


as for the scan code reader, of everything i have used i like the cheap autolink reader, it reads and clears obd2 codes lets you read live data, stores freeze frame data and shows readiness monitors. and the best part is they are less than $50.

http://www.amazon.com/AutoLink-CAN-OBDI ... 508&sr=8-1

if you want something more advanced that will read bmw specific codes i cant really help. i know i dont like the bav auto thing with the analog number and the chart you have to find the car and code to get the fault information i find it irritating. other than that all of my experience is with scanners that cost 10k +

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#77 nasa spec 3
e36 M3

I've got a generic OBDII reader and it works as well as all but the $10k+ autologics, etc that sean mentioned, at least in my opinion....

Code readers are not the be all, end all- but they can give you very useful info that can be used with other data to figure stuff out. For example- my wife's car (2002 325iT) was throwing a code for a bad secondary air pump. I almost fell for it, and I would have probably put a "new" part on the car if I had one laying around, but I did a quick search for that code and that car online and found a couple of folks who had the same code that turned out to be a broken vacuum line on the back of the cyl head that goes to the secondary air valve (EGR thing). I got out my handy mirror on a stick and found out THAT was my problem too! Took me 0.05 cents worth of new vacuum hose and 20 minutes trying to fish the end of that little bastard on the fitting back there and it was good to go!


This is the reader I have:

http://cgi.ebay.com/ebaymotors/Actron-C ... 0313057690

just to add to the list...have you had the injectors flow-tested and serviced? Since you say they are original, I can tell you there was a fairly dramatic change in car performance/starting when I did that to the E30. Sent them off to Cruzin Performance and $100 later I had like-new injectors, complete with flow data before and after servicing.

I don't know how injectors alone would cause your particular situation, but I wonder if the answer is not a multitude of small issues compounding themselves and manifesting in autox driving.

Good luck!

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Steve Carter
1972 Datsun 240Z-- resto pics at http://picasaweb.google.com/srcartermd
2007 GPW Honda S2000-- STR 86

No, never pulled the injectors on the car, but have thought about it. I'll just go the cheap route for now and test the fuel pump I'm getting from Bret. I'll also pick up a code reader since everything I now own is ODBii.

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Rodney

'08 Bullitt mustang, CAM 7
Autox VP '09-'10, President '11-'12, interim President 2nd half of ‘14
proud recipient of the Bowie Grey service award '12
Now just a guy driving a mustang....

Given the car runs fine during the first few runs of an autox, it's most definitely not related to fuel injectors. Seems it must be heat-related.

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Keith Q.
2008 Top Gun
http://www.youtube.com/watch?v=KmX8XuZ_DCo&NR=1

poorly managed fuel supply can cause the catalytic converter to overheat, be it from a faulty pump or faulty injectors--even bad timing or O2 sensor can contribute.

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Steve Carter
1972 Datsun 240Z-- resto pics at http://picasaweb.google.com/srcartermd
2007 GPW Honda S2000-- STR 86

This is true, but a blocked converter is blocked all the time- it doesn't come and go.

Simply overheating a converter isn't going to cause the car to completely bog down like Rodney describes, unless it melts down and clogs the exhaust flow.

true enough...if it was a cat-related issue it *should* generate some CEL or OBD-II code as well. Also, that goes against the idea of it being heat-related unless the fuel boils and gets a vapor-lock type of condition, yes?

I guess without AFR or EGT info it's a bit of shooting in the dark....

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Steve Carter
1972 Datsun 240Z-- resto pics at http://picasaweb.google.com/srcartermd
2007 GPW Honda S2000-- STR 86