Fuel problem??

Ok. First let me say that I am unexperienced when it comes to cars, so if I sound like I don't know what I'm talking about, I probably don't!. The problem with my sunfire is that when it seems to have warmed up or the weather outside is mild, it starts to chug and almost stalls when I have the car stoped. The rpms just keep lagging to about 400 or 500 and then it jumps up to about 1200 and than back an forth. Also, sometimes I'll be driving in 3rd gear lets say with the rmps around 3000 and when I take my foot off of the gas, the car also starts chugging as if I'm just learning how to drive standard!! (oh..car is standard by the way). The car is at the garage, but of course it won't do anything for him, so he's not sure what the problem is and I'm getting frusterated. He's cleaned out the fuel injectors, replaced the fuel filter, etc, but it's still doing it to me. He's also checked the engine, and everything is reading fine.

Any suggestions?? Has anyone had anything similar occur?

A studder or lagging is often due to fuel problem or ignition. I would check your fuel pressure and if that checks out and your haven't changed the plugs and wires in a while do that. Good Luck and welcome to AF.

John

i have a 98 sunfire doing the same thing when the weather gets nice it it wants to stall at stop lights or it jumps up and down like am learning to drive a stamdard. but mines a automatic. wre clueless

i have a 98 sunfire doing the same thing when the weather gets nice it it wants to stall at stop lights or it jumps up and down like am learning to drive a stamdard. but mines a automatic. were clueless

Dont know if you found a solution to you problem or not, but the fuel pump is located within the fuel tank and is cooled by the fuel within the tank. So if your fuel is low or its warm outside your pump overheats and acts up, causing the car to buck and or have no throttle response. I had to replace mine. Luckly it was under warrenty. It can cost between 700 and $1000 to do the job at a garage.