2002 Alero cranks but won't start
I have joined the ranks of Alero owners who are reporting the "cranks but won't start" problem. I have read though all the posts about this condition being caused by a passcode key issue. My situation is slightly different from everything I've read so far and I wonder if anybody has some suggestions of what I might try to diagnose this problem
The car is an '02 Alero 3.4L GLS. In the morning when the car's been in the garage all night it starts on the first attempt; it doesn't even crank for more than a rev or two. Once it has been parked all day in the sun at work it's a different story. It may take 10 or so attempts to start. I let it crank for no more than 5 or 6 seconds each attempt. There are no blinking security lights or any other trouble indicators. After the failed starting attempts, if I smell the tailpipe there's no hint of raw gas odour. Once it does start, it runs smooth, no problems and very responsive ( for an Alero ).
I recently changed the spark plugs and wires and had the fuel pump tested; it's in spec. I've gone through several tanks of gas, so I don't think it's condensation. At one point the inside cabin lights came on and wouldn't turn off - even if I opened and closed the doors; I had to pull the fuse. There were no trouble codes when I brought it in to GM service. They kept the car for 3 days, but the problem did not occur; it was cool and rainy the whole while.
Yesterday morning it started right up as usual. I put a space heater in the car and let it heat up to what it might be after a day in the sun. It took 3 attempts to start.
So... I'm thinking this is a computer problem. I understand that there's a "Body Control Module" and a "Powertrain Control Module" that are both involved in starting the car. Any thoughts on how I might narrow it down to what needs replacing?