Sit for an hour or two the car won’t start unless it sits overnight

JACKHIBBS

MEMBER
2005 CHEVROLET IMPALA
3.8L
V6
2WD
AUTOMATIC
150,000 MILES

After driving for a while and then letting the car sit for an hour or two the car won’t start unless it sits overnight. When it doesn’t start it cranks and the cluster display cycles between a picture of the battery and security. The security light doesn’t flash, it’s on solid. I’ve seen a lot of people online with issues with not starting because of the pass-lock system but everyone says the car doesn’t crank when they have this problem and the security light flashes. I have bypassed the pass-lock system at the ignition with a resistor but I’m still having this problem. If I unplug the BCM and plug it back in then it will try to start but then goes back to the same problem.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Hi Jack,

There are a couple things that come to mind but is it possible to get a picture or even a video of what the cluster is doing because I am not sure why it would cycle through these images. A video of this may help explain what is happening.

You are correct, that usually when it is a security lock out that the vehicle will not even crank. So the fact that it is cranking shows the PCM is allowing power to get to the starter. The other thing to check is to pull a spark plug and see if you have spark which this is happening. If you have spark then we most likely have a fuel issue, but we can pretty much rule out any issue with the security system because it will never allow spark if that is the issue. If you have spark, put a fuel pressure gauge on it and see what that is doing.

Here is a resource that will help with crank no starts, assuming you have spark when this is acting up. If not, we could have an issue with the security system. Last, it would be helpful to see if there are any codes in the computer.

Let me know and we can go from there. Thanks

https://www.2carpros.com/articles/engine-cranks-excessively-before-starting