Dies at Idle when cold
06-22-2014, 09:01 AM
#1
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Dies at Idle when cold At my wits end here!!
Mostly Stock 93 Z.
After replacing many parts and looking for any obvious things, I cannot find why the car is doing this. No codes. I dont know why, but it seems worse with the temperature (for the heater) in hot mode.... I know its crazy! Im sure the air is bled out of the cooling system. Car runs cool and fans cycle as normal.
Car starts perfectly, idles well for a few minutes, then just dies like someone turned the key off. Starts back up perfectly.... ususally does fine as it gets warmer. Drives down the road well, full power at all rpms.
I removed and looked at the o2 sensors. They were black like a fouled plug. I wiped them off and hit them with some compressed air & reinstalled.
What parts of the system are involved when cold idling that I could have missed?
Heres whats been replaced in the last 2 weeks
MSD opti (loctited rotor screws)
FPR
ICM
MSD Coil
Packard 8mm wires
NGK Irridiums
Map sensor
EGR valve
EGR solenoid
EVAP solenoid (was throwing a code 26)
Replaced In the last 2-3k miles
Water pump
Radiator
temp senor (in pump)
temp sensor (in head)
Oil PSI sender
IAC
O2 sensors
Mostly Stock 93 Z.
After replacing many parts and looking for any obvious things, I cannot find why the car is doing this. No codes. I dont know why, but it seems worse with the temperature (for the heater) in hot mode.... I know its crazy! Im sure the air is bled out of the cooling system. Car runs cool and fans cycle as normal.
Car starts perfectly, idles well for a few minutes, then just dies like someone turned the key off. Starts back up perfectly.... ususally does fine as it gets warmer. Drives down the road well, full power at all rpms.
I removed and looked at the o2 sensors. They were black like a fouled plug. I wiped them off and hit them with some compressed air & reinstalled.
What parts of the system are involved when cold idling that I could have missed?
Heres whats been replaced in the last 2 weeks
MSD opti (loctited rotor screws)
FPR
ICM
MSD Coil
Packard 8mm wires
NGK Irridiums
Map sensor
EGR valve
EGR solenoid
EVAP solenoid (was throwing a code 26)
Replaced In the last 2-3k miles
Water pump
Radiator
temp senor (in pump)
temp sensor (in head)
Oil PSI sender
IAC
O2 sensors
06-22-2014, 07:38 PM
#5
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Fuel pressure reads 38 KOEO 39/40 engine running. I even had the opportunity to watch the gauge while it was experiencing its "issue"...it remained at 38-40 psi even after it stalled out. The fuel pump and filter were also changed about 2 years back, but low mileage was put on the car even after the new pump.
thank you
thank you
06-22-2014, 11:24 PM
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Decided to go out for a drive tonight. Started up first hit of the key. Idled fine for about 4-5 minutes...stubled hard almost stalling, but it caught itself and kept running...this happened about 3 more times. When the engine was warmer, it stopped caughing every few minutes and idled fine.
This has been the problem for the most part...the shutting off completely seems to only happen with the heater in the hot position....
Out on the road, it drove perfectly. Went to the store across town with stop lights and all normal conditions. Didnt miss a beat....
I cant pinpoint the isssue.... it also seems to run richer when it happens, but it is running open loop at that point....
This has been the problem for the most part...the shutting off completely seems to only happen with the heater in the hot position....
Out on the road, it drove perfectly. Went to the store across town with stop lights and all normal conditions. Didnt miss a beat....
I cant pinpoint the isssue.... it also seems to run richer when it happens, but it is running open loop at that point....