I have a 95 monte carlo z34 3.4 L v-6 and first thing in the morning when I start my car it revs itself to 2000 rpms like any normal start but when it comes back to 1000 rpms it stalls. so when I start it again to keep it from stalling I give it a little gas for a few seconds then I let it be but it'll rev on its own to 2000 rpms for a second then back down to 1000rpms then back to 2000 rpms. It goes back and fourth like this for a few minutes. well today I woke up a little late and was in a hurry so I started my car and put it in drive but when I pressed the gas pedal it would not move but when the car revs up on its own like it does when it sits thats when it will move but when it revs down the fuel Im trying to feed it by prssing the pedal will not register or something. so when it finally starts going after a minute it drives rough but I go to a mcdonalds 2 blocks away leave my car running while i grab a cup of coffee and when i get back in my car the check engine light is on but it goes away when i give it some gas. This happens everyday. CAN SOME ONE PLEASE HELP ME!!!

ps I dont have a vacuum leak because i smoke tested it and i replaced the fuel pressure regulator,oil change. oh and my catalytic covertor is bad!

Thanks for taking the time reading my post

 

I think you may have answered your own question. Get that cat changed and see if that fixes the problem. Plugged cats can do some weird things. When mine was going the car would idle fine but when you gave it gas it would bog down, given enough gas it stalled the car. Sounds sort of like what is happening to you.

 

Yep, clogged/failing Catalytic Converter = Stalling

 

It only happens in the morning/first start of the day or if I let it sit for 8 or more hours...?????

 

I'm throwing this out there, I'm not positive on it but if that cat is clogged just enough so that when it is cold it causes the problems, but once it heats up say after your car has been running, it could start to break down some of that junk clogging it. after you let it sit for an amount of time it just re-solidifies and clogs it up again.

 

ok thanks I'll replace it as soon as possible! I knew I should of done it when I had the chance but I'll do it when I get to class monday. Thanks for the help and confirmation !!!!!!!!!!!!!!!!!!!!!

 

Ok, just got my 04 SS Itimidator 5 days ago. Was running like a champ. About 99xxx miles on it. I guess when I'm steady on the gas let's say 40 mph, it kind of intend to jerk a little then stops. On the freeway same thing. 65mph steady on the gas then jerking. Feels like my fuel system is clogged or something but I don't know if it is. Could it be the same problem? Can you guys help me?

 

I have a 2000 Monte carlo ss and it stalls sometimes while driving or idle I have replace the fuel pump, the therosat,the water pump, the crank shaft sensor, and the oil pressure sensor, but it still stalls what can I do I,m outta my league I think.

 

If you believe it is a fuel problem, you can run a can of seafoam and see how that does. Just stick it in the gas tank. If it's an Intimidator, you know that it requires premium fuel? Just making sure. Also have you noticed anything else? Any check engine lights? Is it running hot? Is the oil pressure low? The more you notice the easier it is to diagnose your problem. By the way it's described it sounds like more of a trans problem to me, they are said to be the weak point in Montes. Perhaps when shifting into overdrive. Maybe get a trans fluid flush if all else fails. I'm just throwing some ideas out there so that you aren't completely stuck! I hope this helps even a little bit.

 

This sounds more like a clogged cat, such as the OP's problem. I'd give that a try, or just cut it off and see if that helps Unless you have inspections in your area, then that might not be a great idea, however if you have it cut off and the problem persists than you can just have it welded back on. Or if you're handy with a blowtorch you can do it yourself.