For the past 2 weeks or so, on most mornings, and 1 or 2 afternoons, when i go to start my car, it idles very roughly (almost like when i put a spark plug cover on wrong, and a cylinder wasn't firing) until i rev the engine a time or 2.

The other morning i went to start it, and it didn't start at all, unless i held my foot on the gas when i cranked it. Then it idle very roughly and blew smoke out the back. Generally, during the day, it starts fine. I haven't noticed any problems on the highway.

I took a video this morning here: http://www.youtube.com/watch?v=XiP8rWnfB4A
You have to turn the sound up to hear the engine...

it's a 1999 Malibu 4 cylinder . I replaced the fuel filter last week, obviously made no difference.

7/8/2010 7:43:08 PM

It could very well be a fuel pump problem along with other various things.

Since it is having trouble starting, your pump may be getting weak and in need of replacement. It almost sounds like it is having trouble getting primed when it finally turns over and runs. Once it's running though, is it running rough the entire time and when you stop at stop lights?

If so, then it could be a dirty MAF sensor; it might need cleaning or in need of replacement. Or it could be that your ecm if fucking up, my ecm went bad on mine and when I replaced it, the same symptoms you are experiencing were fixed.

However, fuel pump would probably be the first point to start with. It is 11ish years old.

Also if you ever get stuck and it won't crank, have someone crank it. While they crank it, whack the fuel tank a few times with a hammer or crow bar. It should fire up, if it is a pump problem.

[Edited on July 8, 2010 at 8:06 PM. Reason : whack, haha]

7/8/2010 8:00:58 PM

Quote :

"Once it's running though, is it running rough the entire time and when you stop at stop lights? "

No it doesn't really run rough at all, as far as i can tell, once it gets started.

Quote :

"However, fuel pump would probably be the first point to start with. It is 11ish years old. "

The problem with that is fuel pumps are like ~$300 from what i can tell, and it requires taking off the fuel tank (which means i probably wouldn't be able to do it myself). So that's going to be nearly $500 to have that replaced from my rough guessing (correct me if i'm wrong).

I don't know if this is related, but when i turn my AC on, the compressor makes a kind of groaning noise for a second or 2 when it spins up after being turned off.

7/8/2010 8:11:11 PM

Quote :

"The problem with that is fuel pumps are like ~$300 from what i can tell, and it requires taking off the fuel tank (which means i probably wouldn't be able to do it myself). So that's going to be nearly $500 to have that replaced from my rough guessing (correct me if i'm wrong)."

You are correct, it's a bitch and a half to do. You have to drop the tank, disconnect all the hoses and straps b/c the pump is located on top of the tank and only way to get to it is to drop the tank. It will be about 200-250 labor costs at a shop. So 500 is about right. You could get one of these guys on here to do it for you though. If you do it, make sure the tank is on empty, it makes life easier.

Quote :

"I don't know if this is related, but when i turn my AC on, the compressor makes a kind of groaning noise for a second or 2 when it spins up after being turned off."

Original compressor? Might be a compressor clutch problem, tough to tell without looking at it or hearing it; bearing might be going bad in there as well. To keep it from seizing up on you, run the A/C at least once a weak even in the winter.

7/8/2010 8:18:51 PM

Do you think this means anything...

If i'm on the highway and i accelerate to pass a car or whatever, when the engine revs up, it sounds a little like the fan on an old home AC condenser unit that's a bit off balanced when its spinning. Everything's driving smooth and all, it just kind of has that oscillating sound.

7/14/2010 10:16:30 PM

As for the original symptoms you described...there are several things that come to mind. The fuel system losing its prime is the culprit here...but how it does it could occur several ways.
1. Dirty/leaking/bad fuel injector(s). If the pintle or ball/disc doesn't close ALL the way, then you end up bleeding down. Sometimes it takes hours for this to happen.
2. Faulty fuel pressure regulator. Same thing...its internal plug valve or seat might not seal well. Same as above for injectors.
3. Fuel pump...well, if it works, it usually works. Most of the time it's a go/no-go situation. This one should be a module, and yes, it drops into the top of the tank, necessitating removal of the tank to replace. It could theoretically be part of the problem, but if fuel pressure is good and the other issues are addressed, I'd say fuck this for now.

As far as the harmonic issue, pretty typical of GM cars with higher mileage. Could be coming from the transmission, could be a motor mount issue, could be the harmonic balancer on the engine. Unless it's really bad, I don't know if I'd mess with it.

7/14/2010 11:17:11 PM

One thing that might help to determine if it is the fuel pump or not is to try switching the ignition on and off a few times before you start it in the morning. This will usually help start a car that has lost its prime(like if it runs out of gas) but might help if the pump is having trouble priming. Also, open your door or roll down your window and listen to the pump prime the fuel line. It should have a consistent sound each time. If this doesnt help that doesnt mean that its not the pump but if it does help, you more than likely need a pump since you already changed the filter.

7/16/2010 11:24:30 PM

^ yeah I had a friend with a Subaru whose fuel pressure regulator went out and he would have to manually prime it like that to get a good start

7/17/2010 10:40:43 PM

so... the check engine light came on yesterday, the Advanced Auto guy read the code and said it was the MAP. He recommended i see a mechanic (probably because i looked like i didn't know what he was talking about... and i didn't). I took it to Meineke, they wanted $160 for parts/labor, and another like $300 for a transmission flush and a fuel system cleaning because the transmission wonks out when the MAP (subtly different than the MAF referenced earlier) fails (although i had to find this out online, they didn't say the problems were correlated).

I said no thanks, bought the part, put it in, and everything is working.

But... how am i supposed to make the check engine light go off?

[Edited on August 5, 2010 at 12:11 PM. Reason : ]

8/5/2010 12:11:06 PM

it should cycle off if the problem is fixed (x amount of key starts or 100-150 miles I think?). That or take it to Advance and tell them you installed the new part and need the code cleared to make sure that the problem is fixed.

[Edited on August 5, 2010 at 12:25 PM. Reason : .]

8/5/2010 12:24:51 PM

It seemed like the light went away after like the 5th time i turned the car on after swapping the part.

8/5/2010 7:06:15 PM