I have a 2002 Olds Alero with the Ecotec 2.2 ...
My wife was driving it the other day, and it ran just fine. She parked it for about 2 hours and when she came back to start it up, the engine would turn over but it would not crank (i.e. would never fire). I tried pulling the trouble codes, but there were no trouble codes in memory. I checked the ignition system - it delivers spark. I checked fuel preasure - it has 58-60 PSI consistently. If you disconnect the air intake and spray throttlebody cleaner into it while cranking, the engine fires and even runs for a few seconds, but it will not operate from the fuel injectors.
I checked the injectors to see if they are getting power. One side of each injector gets 12 volts when the ignition is turned on, just as it's supposed to, but then the ECM is not pulling the other side of these injectors to ground, and therefore they are not firing. I went so far as to remove the injectors and verified that indeed no stream of fuel is comming out (they are simply not being activated). I checked each injector plug with a NOID light - indeed the circuits for each of the injectors are not being completed. The ECM is supposed to pull these injectors to ground via it's "Injector Drivers" (presumably just power transistors configured to operate as switches). I replaced the ECM thinking that this could be the only possible cause, but the car still won't crank (injectors aren't getting any signal). I and my other car enthusiest friends have come to our witt's end. But then tonight I think I may have hit on the cause, and I need an EcoTec expert to help me. I know that these engines do not have cam shaft sensors, and therefore the injector timing can not be comming from cam shaft sensors but rather from another source. I know that the crankshaft sensors provide the timing pulses (like a master clock) for the entire engine. Does the crankshaft sensor plug into the Ignition Control Module, on the 2002, or does it go directly to the PCM?
I'm thinking that if the crankshaft sensor feeds the ICM, then the ICM would then pass it's signal on to the PCM to provide timing for the injectors. But if the ICM were to suffer a minor failure - unable to output it's reference signal to the PCM, would this prevent the injectors from firing? I do know that the ICM works because if it didn't, then I wouldn't be able to run the engine off of a bottle of spray cleaner. If the CSI sensor were to fail, the reference state would stop in either high or low state, and it would stand to reason that the injectors wouldn't fire. Is this right, or is my speculative mind running away with it's self?
If the 2002 EcoTec has it's crankshaft sensor feeding the PCM directly, then the crankshaft sensor's ref signal couldn't be being blocked by a failure of the ICM to output the crankshaft ref signal. So what else could be stopping it? If the CAMOUT signal from the ICM were to stay high or low but cease to oscillate, would this prevent the injectors from firing?
I just really need some help with this. All of the conventional wisdom of myself and my friends has failed. I'm now thinking WAY outside the box here, and I need the oversight of an expert on this motor. Any help at all would be more than appreciated, and the sooner I can get this help, the better.
Thanks in advance,
Jim Butler
I have no reply but the same thing happened to mine Friday. If you find anything out would you please let me know what you did to fix this problem. Thank you. L. Self
Hi I have figured out what was wrong with my car. After beating our heads against the wall we found that all we had to do is turn the key on and leave it on for 10 minutes, turn it back off then start the car. I don't know if this will help you or not but at the least you can try. Hopefully it will save you any headaches. It had something to do with the security system. I hope this helps.
Yes allot of people have problems with GM's Pass-lock systems all you need to do is reset the computer by leaving the ignition on accessory but the car not started for 10 min then turn the ignition to the off position then start the car.
