Another hard starter

[1843lamp]

I think the Most common problem for the earlier e30 cars is idle and starting issues .I have read many postings on this I have also noted how few return and report what was found to be the issue.My 86es has had a hard to start when warm problem since I bought it about 8 months ago.the car starts normally when cold never touch the pedal and fires on the first turn it goes on to run quite normally but when it is turned off and you try and restart it will not start unless you hold the gas pedal then it sputters and trys to clear itself eventually in about a minute of running you can gently begin to accelerate and the car will again run and behave fairly normally but it also smells rich when this happens and then goes away.Two different shops told me the AFM was bad so I installed two different known working units this morning the problem remained .One person who diagnosed the AFM Being the problem examined the car and said I still had installed a bad AFM he tried to make his point by unplugging the maf entirely and starting the car ,it started a number of times but as he stated it would not accelerate ,this is where I am now,any thoughts?

[Das Delfin]

these cars have an AFM, not a MAF

This problem is normally solved by replacing your crank sensor but sometimes swapping out the fuel pressure regulator or even the fuel pump does the trick

[15Michaeljoseph]

Is the warm cranking normal? Its not uncommon for a starter to get heat soaked.

As for the rest of the bit... any check engine light? Delphin is correct, i'd bet the fuel pressure regulator.
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[1843lamp]

The car is only a problem when it is warm .It takes about a minute to clear out and begin to rev up,there is a rich slightly smokey smell ,then the car runs as fairly normal ,you just can not restart when it is warm .Both shops never made mention of the sensors just the AFM itself,the first shops said leaking injectors as well but I had them redone and only one was a bit low on capacity ,originally when I first bought the car and pulled the plugs out they were very fouled ,also found whe performing other work on the car the exhaust system was completely broken away right at the base of the header ,so I had originally concluded that might have been giving the oxygen sensor false readings .The car never had check engine...note I am wondering why the car will start right away when warm and idle, with the new AFM in place when you disconnect the AFM entirely?,it will only idle for a short time and obviously you can not accelerate.

[jlevie]

It sounds to me like there is a problem with the cold start system.

[15Michaeljoseph]

Any clouds on startup? Sounds like youre getting too much gas in the beginning.

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[1843lamp]

No clouds on startup,only a sooty smell, from cold everything is normal .I replaced the fuel rail press reg yesterday and it made no difference .I opened the original AFM that I took off the car I can find no physical problems with it ,the two tracks on the strip do not look very bad ,not at all worn through ,I tested it and it has constant resistance changes throughout the whole range up and down up and down ,is this normal for the ETA AFM?

[1843lamp]

I think I have eliminated the AFM as the problem.I tested two different ones today with a power source and the temp sensor and flaps seem to indicate no issues,they both were very similar in operation I think since you disconnect the AFM after it is warm and the car will restart right away that it is related to something that is giving an incorrect message or possibly supplying too much gas once the car has warmed up,the DME might be a problem ?...I will go over the cold starting injector system again to make sure I checked it in a satisfactory fashon .

[1843lamp]

I am still working on this starting problem ,I have changed the cold start injector,the fuel rail valve ,main fuel filter .Today I went to fill the tank with fresh higher octane gas ,the starting problem was worse than ever you can carefully get it started after it is hot but it will barely run and will not accelerate for over two minutes then you can very gradually begin to move the pedal it will eventually clear itself then I took it back to the shop.I tried starting it at the shop had the same issues until I disconnected the AFM the car instantly ran normally but of course would not accelerate ,I did this 3 or 4 times with the same results the car started right away first turn using no pedal and it idled normally .

[uturn]

Normally the fuel pump check valve. Put a guage on the fuel line and see if the pressure drops after you turn off the car.

[1843lamp]

Thank you for that suggestion,that was one of the next things I was going to do ,but I put that off because I don not see the relationship between disconnecting the AFM and fuel system ,I am thinking there may be a communication problem between the AFM and the computer?

[1843lamp]

[QUOTE=1843lamp;4646410]I am going to reply to myself since no one else has commented ,and for the Benefit of others with similar issues ,I will be one of the few to ever come back and share what they believe the heart of the issue was.i have slowly and painfully testing and swapping out individual parts one at a time to try and find the real issue ,yesterday even though i with my feeble brain could not see a good reason to do so other than a few comments being made that the oxygen senser can contribute to running rich issues and idle ,I decided it was time to install a Nos original sensor the I found on eBay about 4 months ago.Today I started the car ,it ran a little rough time for a minute ,I decided to take the car home about 10 miles ,I got home and shut the engine and then tried to restart it started right up with no pedal ,then I parked the car in the sun and for the next three hours went out and started the car ,I had no starting issues.I realize that others have reported similar results only in a day or two to find the car seems to revert back to its old ways and the original problem persists .,I am happy today after owning the car for 9 months and hardly driving it at all because of this issue and many others we will see in the next week what is truly going on ,it is ironic because I was told when I bought the car on eBay everything was in great working order ,the car is in very nice original condition physically after 9 months of mostly detail work and cleaning I think I can start driving it .I think I should have waited to post,took it out for another drive and it started right away but took about 15 seconds to clear out and accelerate...to be continued...