Thread: Need advice.. Not supercharged

Alright. So a few months ago, I bought a 2000 2dr Grand prix gt coupe. Originally what I noticed it was brakes all the way around, front struts (springs to be exact) were broken in half and the fuel gauge didn't work properly. Well I took it to a good friend of mine who is a damn good mechanic and he told me what else was wrong with it which mainly involved the motor itself...


This past week I spent over $500 on just parts; radiator, spark plugs, plug wires, lower radiator hose, vacuum line harness and all 3 ignition coils; due to a MASSIVE coolant leak, misfire and the harness being split and or torn at every rubber adapter pieces.. I'm still having issues with the her.. the rpms run high when driving, when I go to press the brake the right front squeaks really bad, and also when I brake the rpms drop from 2000 to in between 700-900 sometimes lower then go back up...

I've replaced the front brakes and rotors along with the strut assemblies. I know there is a code about the mass air flow low circuit (something along the lines of not getting enough voltage to it) but I wouldn't think it would cause that much difference in rpms and what not..

I paid $1800 for the car and I'm not sure if I should continue throwing money into it or if it's time to get ride of her. She has roughly 250k already

Total amount replaced: $1198
Total amount left to fix: $ 1179

Sounds like the MAF or the wiring to it is suspect. If the MAF is not working it will do all kinds of strange things. I'd start with removing the wire connection to the MAF and testing for proper voltage and make sure the wires aren't cooked. If voltage is good there then I'd start with trying to clean the MAF with the correct cleaner (NOT brake cleaner). If the MAF is shot then pick a stock one up from a JY and throw it on.

All those parts you mention sound like normal maint. items to me. I have a 2000 GP also and they will keep running just with normal maint. FYI, I have 488K on my GP and it's my DD. The only thing that does not work is the parking brake. I wouldn't throw in the towel on it at that low of mileage.

Honestly I wouldn't know what 'normal' maintenance for a GP or any vehicle small than a 2500 truck. With every vehicle it's different and also the fact that I'm not a car person. Gas engines are different compared to diesels which is mainly what i know how to fix. My go to person about cars was my brother but he unfortunately passed away at 22 on his way to work.
I wouldn't never use a cleaner that is made or specifically uses another name on a different part. If it's not made for what I need it for then I'm using it.
Before I fixed the radiator I had a code for oxygen sensor 2 but after I connected the battery afterwards i no longer have it. Which the code was insufficient active. So with what you're saying and that O2 code I'm wondering if a wire is shorting out, broken or cracked within the engine wiring harness or the ECM.
Another thing what is normal temperature gauge reading? Mine usually sits under the big 2nd mark between the top 2 smaller ones the whole time I'm driving. Then when I'm at a stop light or going 30 and under it goes between that same big mark and 210 til I go back to speeds above 45mph. Does that sound normal to you? Cause it doesn't to me but that's my opinion.
Appreciate the help tho!

How would you go about checking if the booster is bad or not?

Gotcha, no problem. I feel the same way when I get asked to work on a diesel, lol.. Let's concentrate on the MAF issue first. I'd leave the O2 sensor alone for now. If it's an issue we can figure that out later. One step at a time.

FYI, that temp reading sounds normal for a 3800. These engines run warm normally. Could be some air in the system after the rad. change if the system wasn't bleed correctly which may account for the fluctuating guage.

If you look at the thermostat neck there is a small bleed screw on top of it. Get the car to full temp and loosen the screw up. Should only take a few turns to open it up, no need to remove it completely. Once you get a steady stream of coolant from it then it should be good. I usually shove a rag around the area so it doesn't pool up in the depressions of the lower intake. It may take several times of opening this to get the air out so be patient. I usually help it along by manually pulling the throttle up a bit to around 1500 to get the coolant moving for a minute or so and then let it idle and crack the screw open again.

Originally Posted by FordMan77

Gotcha, no problem. I feel the same way when I get asked to work on a diesel, lol.. Let's concentrate on the MAF issue first. I'd leave the O2 sensor alone for now. If it's an issue we can figure that out later. One step at a time.

FYI, that temp reading sounds normal for a 3800. These engines run warm normally. Could be some air in the system after the rad. change if the system wasn't bleed correctly which may account for the fluctuating guage.

If you look at the thermostat neck there is a small bleed screw on top of it. Get the car to full temp and loosen the screw up. Should only take a few turns to open it up, no need to remove it completely. Once you get a steady stream of coolant from it then it should be good. I usually shove a rag around the area so it doesn't pool up in the depressions of the lower intake. It may take several times of opening this to get the air out so be patient. I usually help it along by manually pulling the throttle up a bit to around 1500 to get the coolant moving for a minute or so and then let it idle and crack the screw open again.

I prefer diesels in Semis over gas and electric vehicles anyday lol. I can take apart a DD15 or cat, fixed what's wrong and put it back together in no time.

So I didn't bleed the system that way. I put 50/50 mix in the radiator, I pumped the lower radiator hose a few times to get coolant into the water pump and such then repeated that a few times till the level in the rad. didn't go down. Then I started the car with the rad. cap off got it up to tempt then idled for a few minutes to let the air out. Turned the key to off, let it cool down and checked. Once I was certain there was no leaks or any other problems I filled up the radiator. But I guess after driving it for 2 days the upper hose to the thermostat shifted and came lose a little so I was getting a leak above the exhaust manifold right under it which caused the car to smoke under the hood which freaked me out cause I thought it overheated but soooo glad it didn't. Fixed the hose and haven't had anymore problems with her involving low coolant or leaks.
If that tempt range sounds normal then I won't worry bout it til it gets up there quite a ways.
I don't have any rattling sounds or clogged converters and it hasn't given me any problems that I can physical hear, feel, or see so I guess that's good.
For the electrical voltage testing I'd have to wait til tomorrow since my voltage tester is at my place of employment.

Originally Posted by FordMan77

Gotcha, no problem. I feel the same way when I get asked to work on a diesel, lol.. Let's concentrate on the MAF issue first. I'd leave the O2 sensor alone for now. If it's an issue we can figure that out later. One step at a time.

FYI, that temp reading sounds normal for a 3800. These engines run warm normally. Could be some air in the system after the rad. change if the system wasn't bleed correctly which may account for the fluctuating guage.

If you look at the thermostat neck there is a small bleed screw on top of it. Get the car to full temp and loosen the screw up. Should only take a few turns to open it up, no need to remove it completely. Once you get a steady stream of coolant from it then it should be good. I usually shove a rag around the area so it doesn't pool up in the depressions of the lower intake. It may take several times of opening this to get the air out so be patient. I usually help it along by manually pulling the throttle up a bit to around 1500 to get the coolant moving for a minute or so and then let it idle and crack the screw open again.

Bad news.. I no longer have to worry bout this car anymore.. got rear ended while waiting to make a left turn at an intersection.. the person who hit me fled the scene before I could even park and get out so didn't catch anything off it.. the passenger side is pushed forward. Support frame is broke, rear struts pushed through the trunk, trunk lid won't shut, are are angled and crooked. Just totaled my car..

I appreciate the advice and everything