I looked through the other threads as much as possible without much luck as to finding an answer to my issue.

I have an '02 Monte SS with about 94K miles that's just recently begun to act up. At idle and off-idle, the car runs fine, but it won't immediately start, and usually requires a bit of throttle to get it to finally run. It's not posting a CEL nor throwing any codes, so I don't have a lot to go off of.

My initial thought was possibly the fuel pump, but off-idle and even hard acceleration is possible with no issues. Reading through the other posts made me wonder about the MAF sensor, but I'm curious as to why it would idle and drive fine, but not start well. Someone also mentioned crank position sensor, but again, why would starting be affected an not the actual performance of the car?

Any help would be appreciated!

 

I've got what sounds like the same issue. I sometimes have to give it a little bit of throttle for it to start. Doesn't do it all the time either. No idea why this happens but I'm curious to find the answer...

 

So I've got a bit more info, though again, not too terribly helpful.

I've noticed that it starts fine when it's been sitting for a while. For instance, first thing in the morning and after work, it starts. But when I drive to the gym after work and come out an hour or so later, I run into the starting issue. Once you tip into the throttle it goes, but I'm curious what this could indicate. I may be getting paranoid, but I almost think it smells a bit rich too, though that could be coming from any unburnt fuel during attempted starting.

Again, any help with this will be appreciated. I'll continue to update with any info/developments.

 

Well, after doing a bit more reading and troubleshooting, I narrowed it down to the fuel pressure regulator, which multiple people had said tend to go out around 100K miles. After I shut the engine off, the pressurized fuel would leak past the regulator, into the vacuum line and throttle body, giving that "rich" smell. After a little bit the pressure had leaked down, and extra fuel was in the throttle body, giving it that stumble on starting. If I waited a long time (overnight), the fuel would have evaporated, alleviating the problem. I replaced the regulator, and all symptoms have disappeared. Hopefully this helps someone else.

 

That was a well solved case of your car acting up, acted on the slightest clues, added it all up, and you were left with the the truth, the fix. Good thread, I like running across these ones

 

THANK YOU MUCH!!!!!! exactly whats going on with me!!!! THANKS!!!!

 

A thanks from me as well! A real nice fix!