Weird Cold Start Issue '05 6 Speed
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Weird Cold Start Issue '05 6 Speed
Hello everyone, Im having a very weird issue and need some advice, car is 05 6 speed, LS3 swapped and cammed.
When the car is cold and I try to start it, It starts and dies immedietly, but If I start it and start to move it asap (its like a 1 sec window) car wont dies and works normally, but I have to drive it like at least 100 meters, Once it starts to warm it never does it again. When its warm I can leave it idling, start it and wait it just works fine. I suspected fuel pump first but fuel pressure seems fine. Is ECU going bad or its just a sensor issue?
Any advices will be very helpful
PS: I havent done anything new to the car in 2 years, It was working fine without any issues
When the car is cold and I try to start it, It starts and dies immedietly, but If I start it and start to move it asap (its like a 1 sec window) car wont dies and works normally, but I have to drive it like at least 100 meters, Once it starts to warm it never does it again. When its warm I can leave it idling, start it and wait it just works fine. I suspected fuel pump first but fuel pressure seems fine. Is ECU going bad or its just a sensor issue?
Any advices will be very helpful
PS: I havent done anything new to the car in 2 years, It was working fine without any issues
Last edited by ogulcanio; Sep 14, 2021 at 02:02 PM.
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From: Cape Coral, Florida
Hello everyone, Im having a very weird issue and need some advice, car is 05 6 speed, LS3 swapped and cammed.
When the car is cold and I try to start it, It starts and dies immedietly, but If I start it and start to move it asap (its like a 1 sec window) car wont dies and works normally, but I have to drive it like at least 100 meters, Once it starts to warm it never does it again. When its warm I can leave it idling, start it and wait it just works fine. I suspected fuel pump first but fuel pressure seems fine. Is ECU going bad or its just a sensor issue?
Any advices will be very helpful
PS: I havent done anything new to the car in 2 years, It was working fine without any issues
When the car is cold and I try to start it, It starts and dies immedietly, but If I start it and start to move it asap (its like a 1 sec window) car wont dies and works normally, but I have to drive it like at least 100 meters, Once it starts to warm it never does it again. When its warm I can leave it idling, start it and wait it just works fine. I suspected fuel pump first but fuel pressure seems fine. Is ECU going bad or its just a sensor issue?
Any advices will be very helpful
PS: I havent done anything new to the car in 2 years, It was working fine without any issues
Maybe bad ECT sensor or dirty throttle body. After the car sits overnight look at your coolant temp and compare it to the outside air temp…should be close !!
Last edited by C5 Diag; Sep 14, 2021 at 04:57 PM.
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Car has a speed density tune, I was using the same tune for like 2 years, I went to the tuner and he checked everything about the tune, everything seems normal.
So the verdict is, If ECT is below like 90 ish degrees. Car starts and dies immedietly, but even in neutral if the car is moving, it works perfectly. And after 90 degrees it never shuts itself down even when its not moving.
Last edited by ogulcanio; Sep 17, 2021 at 07:59 AM.
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Maybe crank sensor ??…I’d suggest taking the car to a “diagnostic” shop and hopefully they can scope 4 or more circuits or sensors and see what’s dropping out when the car dies…if not you’ll be changing a ton of parts !!
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Disabling the VATS
Trying a new BCM (they said they have seen some 05s with the same issue)
and last: a new PCM
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Joined: Sep 2013
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From: Cape Coral, Florida
Was it a diagnostic shop or just a "Bob's Auto Repair" ??...I highly doubt the PCM is shutting off enough of the "driver" circuits in the PCM to allow the car to shut down...there is a separate driver circuit for each injector...I hope they're right !!...I'd ask them if they are going to "buy" that mistake in case it's not the engine computer ??
Last edited by C5 Diag; Sep 18, 2021 at 05:04 PM.
