2000 Pontiac Sunfire GT Randomly Loses Power

[Karan]

I have had this car for 8 days, and i love it. Its a 5-Speed manual and i have not had one single preblem with it until today... So its April and almost 4 inches of snow gets dumps on us, I'm driving my new (but its used) car to school when out of no where I hear sveral beeps. The same kind of beeps that sound when you leave your lights on and get out of the car. And suddenly my engine loses power. My powersteering is gone, but my brakes still work. I take out the key, put it back in and it starts right back up! It happened 2 more times on my way home! I love this car but I'm almost afraid to drive it again . It wouldnt be a wire shorting out because then I would have lost all my power an would not be able to turn it right back on. Please help!

[manicmechanix]

It kind of sounds like your ignition switch is intermitently breaking connection or somewhere in the the ignition wiring it's intermittently losing connection.

[Karan]

That appears to be what the problem was because I tryed giving it a jump this morning and it wouldnt start. After I slammed the hood down in a fit of anger I tryed it again without the cables and it started right up. Ill be getting it fixed on monday.

Thanks so much! I really appreciate the help.

[J-Ri]

You can do a couple quick quick checks before you take it in. Slamming the hood and having it start (or bumping the cable ends when removing the jumper cables) could possibly mean loose battery cables or a broken wire somewhere. Clean the battery cable ends and tighten them up, and with the engine running, wiggle all the wire harnesses you can see. If the engine dies, you have found the general area of the fault.

Loose battery cables will cause the system voltage to drop so suddenly with a load (such as your brake lights, sounds like you were slowing and turning when this happened?) that the alternator can't adjust it's output fast enough and voltage goes below the point where the PCM can function.

[Karan]

Thats pretty much right on, I was indeed slowing down and turning when this happened.
As for wiggling all the wires, I did that to all the ones I could see and nothing happened (and the car was running) then I decided to shut a few things with some force to see if that did aything. And sure enough, after I shut the hood and the passenger door a little harder than normal it lost power. The weird thing is I hit bumps on the road harder than that and this has never happened before.
Either way, I am still going to get the ignition manafold replaced and if there are anyother problems I'll do it myself. I normally do stuff like this myself, but I dont have a garage the weather refuses to cooperate, so I'll have pros do it so I dont screw anything up.

[Karan]

Alright, I got the new ignition modual in, but this morning it did almost the same thing as bfore. I started it up but it acctually started up, but then almost imedietly lost power, so it's got to be river the battery wires or the alternator. Anybody got anyother things it might be?

[manicmechanix]

I'm thinking you have a problem in the ignition cylinder circuit not the ICM. When you slammed the passenger door, it probably jarred the passenger side fuse box. You're probably going to need a voltmeter and wiring schematic and start at that fuse box and see if power is cutting in and off.

[Karan]

I'm starting to think thats its just the batter causing it now because I drove it around in the afternoon and it ran just fine. The only thing that confuses me is that in the morning it started up but died soon after, and it was 46 outside, which isnt that cold at all.

[J-Ri]

Did you or the shop ever check those battery cable ends? Just grab them and try to twist them, they shouldn't move at all with a considerable amount of force.

[Karan]

So I took it in once again this morning after it died on me in the middle of an intersection. They did check the wire ends on the battery, and they told me later that day that they think the cause was not only the ignition monafold but the crankshaft sensor. Would this make sense to you guys? Because I'm not entirley sure at this point.

[J-Ri]

Originally Posted by Karan

So I took it in once again this morning after it died on me in the middle of an intersection. They did check the wire ends on the battery, and they toldm e mlater that day that they think the cause was not only the ignition monafold but the crankshaft sensor. Would this make scense to you guys? Because I'm not entirley sure at this point.

Ignition monifold? If they actually said that's a part, take it somewhere else!

It's very possible it's the crank sensor... the thing is if there's no code, you have to watch the CKP reading in the datastream to see if it goes to 0 while the engine's running to confirm that it and/or the wiring is bad, so if it's suspected it's really easier to just replace it rather than wait for it to fail while connected to a scan tool. Things hardly ever intermittently fail with a technician close to the car

[Karan]

I'm pretty sure I ment to say ignition module. But yeah, they said when I brought it in and they hooked it up to what ever it is they hooked it up to, that the code for the crank sensor had been activated.

[J-Ri]

If the code is set, that only means the problem is in that circuit. The way it died when you slammed the passenger door would suggest that it may be in a wire that's attached to the body. The engine mounts would probably dampen the shock enough so that it wouldn't affect the crank sensor itself or wires on the engine. Or maybe not, or maybe it just died on it's own at the time you slammed the door, it's hard to say. I would suggest just replacing the crank sensor and see if that fixes the problem, of course that is assuming that they checked for obvious problems with the wires when you took it in.

[Karan]

Well, I got it back in Monday, it started just fine on Tuesday morning but then barley started this morning and once again died. This time the check engine light remained on and it took a good 10 minutes to get it started again. Could perhaps the fuel pump be the third problem now?

[J-Ri]

It's possible. Check the fuel pressure. Also check what code set, it's possible the problem was originally in the wiring for the CKP sensor and not the sensor itself.