Intermittent FUEL PUMP

[CavyCT]

The fuel pump doesn't always come on when I turn the key forward... sometimes it won't work for days so I get stuck places. I don't want to replace the fuel pump if it's an electrical problem or something else.. when I brought it to the shop in town it worked perfect, they had it for two weeks, the next time I drove it -- it stalled in a drive thru and had to push it out of the way. Its a 2000 Z24 with less than 70K miles. If anyone has any advice on what to start with that would be super. THANKS!

[deadBird]

Perhaps a wiring short.

What makes you think it's the fuel pump?

[CavyCT]

I don't know what it is, I thought the fuel pump might be going out, that's why it doesn't work all the time. But when it does work it sounds normal.

I don't know how to check for bad wires because i don't know what wires are for what, but that's probably what it is since it starting happening when the weather got warm and humid. Do you have to drop the gas tank to check the wires running to the fuel pump? And if I find a bad wire, which I had before in the lights, is there a good way to fix them without resoldering? Like some connector that doesn't look tacky? Sorry for all the ???'s but I really want it fixed. Any advice would be greatly appreciated. Thanks

[leojleblanc]

Originally Posted by deadBird

Perhaps a wiring short.

What makes you think it's the fuel pump?

Just to put my 2 cents worth in, I have a 2001 sunfire and I was having similar problems. the car would be working great, starting up with no hesitation for weeks on end, then all of a sudden, nothing. It would try to turn over but never take. I brought it to a local shop who diagnosed the problem as the fuel pump. I didn't have the money to fix it right then and there so they got a rubber mallet and gave the gas tank a bit of a tap and the car started up. I ended up doing that a few times until the pump had to be replaced.

[CavyCT]

Yeah, I have a mallet I carry with me...it hasn't worked to start it but at least it's amusing for people to watch someone crawl under their car with. So you haven't had a problem with it since you replaced the pump? I'm going to do that next week... hope that's it and I can quit thinking about it. Thanks for your 2 cents!

[deadBird]

Ahh humid... check your coil pack thoroughly for cracks of any kind. I've heard of them running rough when it's humid & bad. When it rains does it get worse?

[00 cavalier 2.2]

im having similkar problems as leojleblanc.

car will run fine and continue running. but sometimes it wouldnt star back up, and not for hours or days at a time.

ive replaced the fule pump once already and now the new one quick working in only 8 days.

i took the new one out, hooked it direct to a battery and it worked fine. hooked it back up to the car and it wont work.

im getting voltage at the connection to the pump.
but its only 9.6 volts going to the pump while cranking the engine. is that not enough to run the pump?

does anyone know how many volts the pumps needs while priming (first two seconds of ignition in ACC position)

and how many volts the pump needs whiel cranking the engine(trying to start it)?


any help would be greatly appreciated
-eric

[CavyCT]

STILL having problems. Sorry I don't know ANYthing about voltage. What do you use to check it? I'll have mine checked. Otherwise sounds like similar problems, I've replaced the fuel pump, car worked perfect for about a week, then one morning it started really hard.. it would turn over fine, run for a second or so and quit.. like the car was stuck in Start mode.. but as soon as u would turn the key to on it would quit.. it did that and about an hour later it quit on the road and hasn't started since. Now the fuel pump won't turn on when u turn the key forward, hope that doesn't mean the pump is burned out. Does anyone know how to check for bad wires? like where to start? and how to replace the MAP sensor? someone said it might be that... OR ANY suggestions spoken in not too technical terms?? THANK You so much.

[CavyCT]

I had that stuff checked, plugs, coil pack, other maintenance things twice in the last year and everything looked great. It never ran rough tho, when it did run it ran perfect. Just a problem starting and staying lit. The car was in a wreck before I got it so some wires may have been damaged, but I've been driving it with absolutely no problem for almost 3 years since then. I even had no problem starting on the coldest WI winter mornings! Just cuz I need to sell it now..it acts up...figures.