Engine Mechanical problem
2003 Oldsmobile Alero 4 cyl Front Wheel Drive Automatic 160K miles
2003 Oldsmobile Alero
Ok. My car won't start when its above a certain temperature outside (around 85 or 90 Degrees F). Here is what I know so far:
*The fuel pump is good, however doesn't come on when I turn my key to "On". I know this because my car will run at night when its cool.
*I can turn my key off and on and cannot here the fuel pump kicking in.
*When fuel pump does come on, fuel pressure is great.
*Tried replacing fuel pump relay and PCM. Still no go.
* When it doesn't start, I can also here the fuel pump buzzing like crazy. I have switched relays around (relays I know are good), and they all do the same thing in the fuel pump relay spot.
*If I sit with the doors open for about 15 minutes (allowing the inside of the car to cool down), I can usually get the pump to come on, after cycling the key from off to on a few times.
*Problem is NOT type or level of fuel related. I've been buying the same gas from the same place, as well as other places, and the problem has occured on a full tank, half tank, and quarter tank.
*No engine codes. I've had the best mechanics in town working on this. Plugged in a very nice diagnostic computer, and saw the following while cranking:
*Engine RPMs normal
*Fuel Pump Relay Command is staying off.
Thats the problem right there. My computer isn't telling my fuel pump to come on. The mechanics even put a jumper on my fuel pump and it turned on and the car ran fine. What is causing my computer to not tell my pump relay to not power the pump? I don't think it is a Passlock Problem, as my light on my dash blinks like normal. I have also tried the old "leave the key on for 10 min to reset the security system" trick and still no go. I have even disconnected my battery before and left it for about 10 minutes to reset the computer, and still no go.
Monday, November 12th, 2018 AT 3:59 PM