2002 Chevy Cavalier 2.2L engine. Every now and then the car will not start. Turn the key on, fuel pump does not prime. Sometimes a light tap on the backseat will cause the pump to run. Sometimes I have to tap on the bottom of the tank in order to get it to run. The most effective method I have discovered, is to remove the back seat and tap the center hump under the seat with a mallet. Usually then the pump will prime and the car will start. This has been going on for the last 2 years or so.
Every once in a while, the car will die while running. Sometimes it will restart right away, sometimes I will need to tap around with the mallet to get it to start. Usually, once I get the car started, it stays running, however.
Every now and then I experience a momentary loss of power, only for a second or two, and suddenly it surges back. I believe this is the fuel pump ceasing to operate momentarily, and then resuming operation on its own.
The fuel pump has been changed 3 times, filter twice. The last time the pump and filter was changed was by a very experienced and reputable mechanic. I have since taken the car back to him twice after that repair (which was 6 months ago), and both times that he has had it (1 week - 2 weeks), the car only misbehaved once, and by the time they rolled it into the shop, it was working fine (he did not charge me anything for the subsequent visits). He checked the fuse box, replaced the pigtail, checked the harness, tested, probed, ripped apart what he could think of.. still no fix. The previous time that he had it, it behaved for 2 months straight, and then suddenly started having frequent issues when the weather got a bit colder (though its done this on cold days, warm days, warm days going cold, cold days going warm, rainy days, etc). He is about as frustrated with it as I am.
I just picked the car up from them yesterday, after they had it for two weeks. Started and ran fine on the way home. This morning, it would not start. Yanked out the back seat, tapped the sheet metal above the tank.. she started and ran fine all the way to work. Same thing coming home, would not start, tapped and it started. Experienced a brief loss of power one time within the first 5 mins of driving, but after that it was fine.
Talking to some folks, they suggested that it might be the neutral safety switch, or possibly the fuel pump collision cutoff switch. Other folks suggest that it may be the ignition switch, that the car might be going into "theft" mode. I have tried tapping on the steering column a couple of times to get the pump running, but that has not yet been effective. Only tapping on or near the fuel tank seems to work. The starter never fails to operate, and I am not sure whether or not any of those switches would interlock the starter as well as the pump.
This is a very frustrating problem, particularly due to the fact that it seems to go dormant every time I take it back to the mechanic. It is my wife's car, and she absolutely refuses to drive it now. Really don't want to buy a different car at this point in time. I am somewhat mechanically inclined (I replaced the pump and filter myself the first 2 times, before giving up and going to the shop), and I am able to do some diagnoses, though I have no garage, and it is cold here in the midwest, so my abilities are limited. Any help / ideas would be greatly appreciated!!
Thanks,
-Paul
I'm just gonna tell you what you already know... if tapping the tank makes it work, it's something in the fuel pump. There is no fuel pump collision cutoff switch (it's not a Ford).
I would just pull the whole pump assembly and get one from a wrecker and stick it in.
Edited 1 time(s). Last edited Saturday, January 19, 2013 11:00 AM
