Need Help, Car Stumbles At High RPMs
Thread Starter
Teching In
Joined: May 2002
Posts: 4
Likes: 0
From: Anaheim, CA
Need Help, Car Stumbles At High RPMs Under full throttle acceleration, my car stumbles badly (the car is a 98 SS). I've had it in to two Chevy dealers, each of them had the car for two weeks and returned it without figuring out what was wrong. It's not throwing any codes.
What could be causing this?? I called Chevrolet customer service to ask them what to do next, and they told me that the car is operating fine under normal driving conditions so it's not a problem.
I'm getting desperate here, any advice would be helpful. It's getting to the point where I don't enjoy driving my car anymore <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
What could be causing this?? I called Chevrolet customer service to ask them what to do next, and they told me that the car is operating fine under normal driving conditions so it's not a problem.
I'm getting desperate here, any advice would be helpful. It's getting to the point where I don't enjoy driving my car anymore <img border="0" title="" alt="[Sad]" src="gr_sad.gif" />
TECH Resident
Joined: Nov 2001
Posts: 854
Likes: 0
From: san diego ca
Re: Need Help, Car Stumbles At High RPMs and it's not the knock sensor?
Are you getting enough fuel pressure and are your injectors clean? At high fuel demands (like WOT high RPM) less-than-perfect fuel injectors manifest themselves. How many miles do you have on the car?
Does this only happen when you buy gas from a particular vendor? Have you tried switching brands or adding injector cleaner? In practice, that's only for keeping them clean; once they get clogged they have to be removed and have solvent run through them to clean them out.
Are you getting enough fuel pressure and are your injectors clean? At high fuel demands (like WOT high RPM) less-than-perfect fuel injectors manifest themselves. How many miles do you have on the car?
Does this only happen when you buy gas from a particular vendor? Have you tried switching brands or adding injector cleaner? In practice, that's only for keeping them clean; once they get clogged they have to be removed and have solvent run through them to clean them out.
Thread Starter
Teching In
Joined: May 2002
Posts: 4
Likes: 0
From: Anaheim, CA
Re: Need Help, Car Stumbles At High RPMs I should have mentioned this before, but these problems started when I had it at the Chevy dealer to have them replace the fuel pump and the PCM. When I took it back to them, they told me both of them tested out fine though.
I have enough fuel pressure at idle, I don't know if the pressure drops at high rpms though. As for the injectors, how would I check if they are clean or not? There's 60,000 miles on the car.
I've tried switching gas brands, and using fuel injector cleaner, neither helped at all.
I have enough fuel pressure at idle, I don't know if the pressure drops at high rpms though. As for the injectors, how would I check if they are clean or not? There's 60,000 miles on the car.
I've tried switching gas brands, and using fuel injector cleaner, neither helped at all.
Trending Topics
Re: Need Help, Car Stumbles At High RPMs I am having the same problem with a modded 98SS. At 5 grand the damn thing seems to bog down until I shift at 6500. I cant find out what the hell is wrong with it. It just loses power. As soon as its under load, the motor loses its pull, weird and pissing me off.
TTT this guys...we both need some help!
TTT this guys...we both need some help!
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On The Tree
Joined: May 2002
Posts: 191
Likes: 0
From: Phoenix, Az
Re: Need Help, Car Stumbles At High RPMs You need to find out what pump they put in. From what I've read here, the 98's have higher fuel flow. It may be starving at higher RPM if they put a later pump in.
