Well no one I know including the places I have taken my car have been able to figure this problem out. I drive a '00 Cavalier which other than this small problem has been great for me. The problem I am having is the car doesnt want to start when the temperature is like > 90 degrees and it is very humid outside (such as today). This has nothing to do with the engine or car running hot, never has any overheating issues or anything of that nature. This only happens when the physical temperature of outside is very hot. It has no problem actually cranking or turning over or whatever, just wont actually start. Basically from what I can tell the car just isnt getting gas, this is further evidenced by the fact when this problem happens my gas gauge will sit on E while the car is in the ON position. As soon as it has cooled down a bit outside I will be able to go out and it will fire up without issue. The battery lines have been replaced, fuel pump replaced, relays checked, hooked up to computers, etc. Problem is this started 2 summers ago, last summer I worked a night job so I never had a chance to see if it was actually fixed as they claimed it was. Now it is happening again this summer on and off and of course my warranty came up during the winter time. I am at a loss as to what might be causing this and its getting quite annoying not wanting to drive anywhere in the afternoon/evening for fear I will be stranded for hours. So I bring this problem to all you car nuts on the wolf web and hope you can come up with some ideas, any other questions feel free to ask I will give as much info as possible.

8/3/2006 6:59:16 PM

wellwhatyou'regonneedtodoistakesomeofdatdereuhkeroseneanduhpouritonthedaggoneengine,thenyagontakeyondermatchandlightit

itellyayourcartroublesbegone

8/3/2006 7:02:52 PM

I'm betting that it happens less if the gas tank is full.

8/3/2006 7:04:12 PM

Negative, I thought about that as well, tank is full right now and this is the first time I have had the issue this week. One thing I have noticed is if I havent driven the car all day and its fucking hot outside it will usually start the first time, but soon as I cut it off and try to start it again I am pretty much screwed, so going to grab some drive through dinner works ok, trying to stop at food lion, not so much.

8/3/2006 7:09:52 PM

you said it was replaced but sounds like a fuel pump issue to me

8/3/2006 7:36:09 PM

Yer gonna laugh...but I bet a large pepperoni pizza from my favorite place, Gumby's, (shut up with yer smart ass remarks)...

...that it's a relay problem. Ten dolla says it is one of your relays. I've seen relays do some crazy shit when the weather changes, especially if they've got some age on them and the inside terminals get a little pitted and oxidized from use. Humidity can do it. Heat can too (expansion or flexure of the contact, or humidity affecting the layer of oxidation, etc.).

I've changed several relays that did this. You just need to hunt down the right one.

OH, and current running through the contacts may heat them up more and prevent them from working the next time around.

[Edited on August 3, 2006 at 7:43 PM. Reason : blahblahblah...]

8/3/2006 7:42:36 PM

^i was gonna say the same. i remember a couple years ago someone had the same prob, i wanna say on a honda. twas a relay prob i beleive

8/3/2006 7:53:01 PM

It pops up quite a bit with Honda main relays, and I know ^you know this. Especially in the heat.

8/3/2006 8:06:33 PM

FYI On the hondas to get them started, a little trick, with the drivers door open, knocking the shit out of the dash where the door and the dash meet will usually get it going.

8/3/2006 8:32:49 PM

Yeah I had come to the same conclusion so I found the relay box under the hood and found the relay for the fuel pump assuming that would be the most obvious culprit, the one for hte A/C was exactly the same so i figured pop that one out, check if the AC is working, it was, so moved that one over and got nothing. I agree to me it sounds like something is either making contact when it isnt supposed to or not when it is, due to the heat causing expansion or what not, only problem is if it isnt the fuel pump relay where to check next.

8/3/2006 8:38:01 PM

What about an ignition relay? Power to the starter but not everything else...

8/3/2006 8:39:33 PM

only way to know is to check the spark strength and fuel pressure with the no-start condition, and hunt down your electrical problem from there

8/3/2006 9:18:44 PM

yeah see if there is not anything labeled as shut-off relay under the hood.. i had one act up on my dodge a couple weeks ago, swapped it and with my a/c relay and the truck started right up.

8/3/2006 10:39:40 PM

im going to say relay issues as well

im having the same problems now

8/4/2006 1:03:55 AM

Though I admit it does sound like a relay/electrical issue, I'd be suprised to see relay issues on a car that's less than 7 years old. Am I being naive, are the relays not shielded from the elements in these cars, or maybe it's a northern car...

Who manufactures the relays on Cavaliers, anybody in the know care to share?
Ahmet

8/4/2006 1:36:09 AM

Well only relays I can find are the ones in the box under the hood, one for like the A/C, Fuel Pump, etc. There isnt one for ignition only a fuse. This happened again today wouldnt start at 3, 6 oclock fired up like it never had anything wrong with it. This is by far the most conclusive evidence of the existence of gremlins yet.

8/4/2006 6:58:42 PM

I wouldn't think the temp would have changed enough in the time to do anything. Was it parked in direct sunlight?

8/4/2006 8:31:02 PM

Im thinking coil

8/4/2006 11:52:44 PM

Yeah, but a Cav has more than one coil. Module heat soak?

8/5/2006 3:00:14 AM

I've been having this same issue with my '96 dodge avenger. My first thought is fuel pump, but when the car actually starts it has no signs of malfunction on the fuel system's part. I haven't actually thought about checking out the relays though....reckon i should do that

8/6/2006 12:53:46 AM