Engine dies when put into gear when cold ??!!??
Thread Starter
Instructor
Joined: Jan 2001
Posts: 126
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From: Murrieta, CA
Engine dies when put into gear when cold ??!!??
Was so successful in finding a resolution to my Code 33 problem on the Forum (turns out the chip just needed to be reprogrammed to increase the GPH setting) that I thought that I would ask for help on another matter. This is it... when the car is cold, in the morning, it stalls (engine dies) when I put it in gear. Takes many attempts to get it to continue to run after put into gear (automatic). Once it decides not to die, it will not exhibit the same behavior any other time during the day... but always in the morning when cold... any ideas ??
Team Owner
Joined: Dec 2000
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From: SE NY
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Re: Engine dies when put into gear when cold ??!!?? (vett4cw)
I would suspect the IAC may be binding when cold or perhaps the coolant temp sensor to the ECM is not telling it to increase idle speed enough when dropped into gear.
You might check out the cold-start injector. The engine may not be getting enrichment till it warms up.
BTW is the IAC movement when going into gear an EPROM function??
You might check out the cold-start injector. The engine may not be getting enrichment till it warms up.
BTW is the IAC movement when going into gear an EPROM function??
Thread Starter
Instructor
Joined: Jan 2001
Posts: 126
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From: Murrieta, CA
Re: Engine dies when put into gear when cold ??!!?? (65Z01)
Thanks for responding... Have replaced the IAC within the past 3 years... and checked within the past month... but who knows, the engine also surges when cold... maybe the IAC is still the problem. Will check both the IAC and the coolant sensor... thanks.
Do not have a cold start valve... took that out a number of years ago when I went to the Acell big mouth manifold and runners (cold start will not fit with these components)... my after market chip, however, is set to widen the pulse width on the injectors for the first minute or so... the problem that I am having is a fairly new problem... so expect that this is not the issue.
IAC counts are definitly a EPROM function, and I expect that the EPROM should be sensing the shift into gear and making the appropriate change to accomodate the shift... good point. I will look into this also.
Do not have a cold start valve... took that out a number of years ago when I went to the Acell big mouth manifold and runners (cold start will not fit with these components)... my after market chip, however, is set to widen the pulse width on the injectors for the first minute or so... the problem that I am having is a fairly new problem... so expect that this is not the issue.
IAC counts are definitly a EPROM function, and I expect that the EPROM should be sensing the shift into gear and making the appropriate change to accomodate the shift... good point. I will look into this also.
Team Owner
Joined: Aug 2000
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From: Sydney, Australia
CI 6-7-8-9-10 Veteran
St. Jude Donor '07-'08-'09-'10-'11-'12-'13-'14-'15-'16-‘17, '22
Re: Engine dies when put into gear when cold ??!!?? (vett4cw)
Can't help you with this one but I'll be watching to see if you get any suggestions that might help you sort it out. I have a similar problem with my 90. IAC is okay and coolant sensor is less than 12 months old.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Engine dies when put into gear when cold ??!!?? (vett4cw)
Cold start lean condition.
Surging and dieing on cold start are most often tracable to a lean condition.
Without having to have the PROM tweaked, you could try raising your TPS voltage setting to .62/.63
IAC counts should be abot 25, closed loop, in neutral/park and increase to very low 40s in drive gear. This gives the IAC the best range of controllability.
Hope this helps.
Jake
[Modified by JAKE, 7:10 PM 6/10/2002]
Surging and dieing on cold start are most often tracable to a lean condition.
Without having to have the PROM tweaked, you could try raising your TPS voltage setting to .62/.63
IAC counts should be abot 25, closed loop, in neutral/park and increase to very low 40s in drive gear. This gives the IAC the best range of controllability.
Hope this helps.
Jake
[Modified by JAKE, 7:10 PM 6/10/2002]
Team Owner
Joined: Aug 2000
Posts: 42,935
Likes: 20
From: Sydney, Australia
CI 6-7-8-9-10 Veteran
St. Jude Donor '07-'08-'09-'10-'11-'12-'13-'14-'15-'16-‘17, '22
Re: Engine dies when put into gear when cold ??!!?? (JAKE)
Thanks JAKE. :)
Looks like I'll be breaking the diacom out to have a look see...
edit Assuming it is a cold start lean condition, is that something that could be traced to one factor (ie: bad injector/s, O2 sensor, TPS or similar??? If so, is there one common factor. Just wondering & I realised I can't tweak the TPS because 90's have a non-adjustable TPS.
[Modified by Red 90 L98 Coupe, 7:06 PM 6/12/2002]
Looks like I'll be breaking the diacom out to have a look see...
edit Assuming it is a cold start lean condition, is that something that could be traced to one factor (ie: bad injector/s, O2 sensor, TPS or similar??? If so, is there one common factor. Just wondering & I realised I can't tweak the TPS because 90's have a non-adjustable TPS.
[Modified by Red 90 L98 Coupe, 7:06 PM 6/12/2002]
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Engine dies when put into gear when cold ??!!?? (Red 90 L98 Coupe)
Thanks JAKE. :)
Looks like I'll be breaking the diacom out to have a look see...
edit Assuming it is a cold start lean condition, is that something that could be traced to one factor (ie: bad injector/s, O2 sensor, TPS or similar??? If so, is there one common factor. Just wondering & I realised I can't tweak the TPS because 90's have a non-adjustable TPS.
[Modified by Red 90 L98 Coupe, 7:06 PM 6/12/2002]
Looks like I'll be breaking the diacom out to have a look see...
edit Assuming it is a cold start lean condition, is that something that could be traced to one factor (ie: bad injector/s, O2 sensor, TPS or similar??? If so, is there one common factor. Just wondering & I realised I can't tweak the TPS because 90's have a non-adjustable TPS.
[Modified by Red 90 L98 Coupe, 7:06 PM 6/12/2002]
Anyone got any other ideas?
Jake
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