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Loss of power AND whining noise above ~1700RPM

AGlass0fMilk

New member
Hello, due to recent events (my Dodge Neon broke down) I have been forced to resort to using my sister's old car (she has since bought a new one).

It's a 2002 Pontiac Grand Prix SE with a 3.1L 6 cylinder, standard everything. There's not much keeping this car on the road, but it still runs and drives for the most part. With more than 222,000 miles it's a miracle.

Anyway, I'll skip the other stuff I've fixed on this car and just jump to now. While my sister was driving it, the car developed a dramatic loss of power. It doesn't shift very well, there is a whining noise coming from the engine compartment, along with check engine codes related to the emissions system (I believe it was the catalytic converter efficiency). Before my sister got her new car, she drove it to work with pretty much no gas in the tank (the gas gauge was erratic and unreliable). I took the car for a spin to see how it was behaving, I parked it afterward, went back out to start it to check the transmission fluid, and it wouldn't start. Got it towed by a friend back to my house and then determined it was the fuel pump which kept burning out fuses.

I replaced the fuel pump, got it running and it had a misfire in cylinder 1. I checked the spark plug (a real pain in the ass compared to my neon and my old MGB!) and found that it was pretty black and deteriorated, merely a pinhead of the center remained. The old plugs look a healthy tan but should probably be replaced soon.

Replaced the plug and the misfire is gone, but the loss of power and whine still remain.

The whine only exists above and around 1700RPM. The car's response is very slow, the acceleration is very slow and I'm lucky to get it up to 60 MPH.

Does this sound like any problem you know of?

At 222,000 miles I know that I shouldn't be hoping for much more out of this car. For now, it's good for a max 25 mile travel radius which gets me to work and school but I'd like to fix the problem if I can.
 


What about a transmission vacuum modulator? It sounds like there's a vacuum leak kinda.

Is there a vacuum modulator on a 2002? And also, how would I check for a clogged cat?
 
When you open the hood.. stand in front of the drivers headlight. Look straight down at the transmission. Right on the front should be the vacuum modulator.
 
Shouldn't be a vacuum modulator on a 02. You could pull the upstream o2 it and if it runs better the cat is clogged.
 


Yes, the whining is coming from the drivers side. Trans fluid was at a good level last time I checked it (after this started happening). I will check it again
 
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