2000 Gran Prix gt 3.8 L IDLE AND RPM`S JUMPING WHILE PARKED AND WHILE DRIVING

[Joeyprix]

I have a 2000 Gran Prix Gt it worked fine since I bought it but recently it can be parked and the idle/ rpm`s keep jumping and if gas is applied than it seems like its bogging out. Also while I was driving doing 100 km on a highway and it did it again
like i said like its bogging out it sputers when the gas is pressed but has nothing.

I was told to buy fuel injection cleaner which i have i will today try that I was also told that if that doesnt work to use brake cleaner and clean the ( IDLE AIR CONTROL VALVE)

PLEASE SOMEONE GIVE ME SOME TIP`S ADVICE ANYTHING THAT WOULD HELP ME DECIPHER THE PROBLEM THANK YOU AND HAVE A MERRY CHRISTMAS EVERYONE.

[olopezm]

Hello Joey,

Welcome to the forum dude!

Yes cleaning the IAC valve is a good place to start, give it a good clean with throttle body cleaner. Clean both the pintle and the shaft at the throttle body.

Also disconnect your MAF sensor and see if it works, it could be dirty too. If the problem goes away when you disconnect the MAF, then you've found your problem. Clean it with MAF sensor cleaner and test if that doesn't works you'll need to replace the MAF.

Another possibility would be a vacuum leak inspect all hoses at the engine compartment. Mine had a vacuum leak at the hose coming out of the throttle body and running to the EVAP purge solenoid.

Try the first two, and see if you have any different result. Hopefully it will be just a dirty IAC.

Merry christmas!

Best regards,

Oscar.

[grandprixgtx00]

Originally Posted by Joeyprix

I was told to buy fuel injection cleaner

I would be careful with what additives you use. I personally recommend using Seafoam. Works wonders.

How many miles are on this GP? How long has it been since a tune-up? Any CEL?? As suggested above, maybe try unplugging the MAF and see if it runs better.

[Joeyprix]

Originally Posted by joeyprix

i have a 2000 gran prix gt it worked fine since i bought it but recently it can be parked and the idle/ rpm`s keep jumping and if gas is applied than it seems like its bogging out. Also while i was driving doing 100 km on a highway and it did it again
like i said like its bogging out it sputters when the gas is pressed but has nothing.

I was told to buy fuel injection cleaner which i have i will today try that i was also told that if that doesnt work to use brake cleaner and clean the ( idle air control valve)

please someone give me some tip`s advice anything that would help me decipher the problem thank you and have a happy holidays everyone.

i have tried fuel injector cleaner so far and even took my idle air control valve off and cleaned it thoroughly
and it has seem to make a diffrence however i could not remeove the maf sensor due to lack of propper tools but thank you for your help hopefully i will get the cleaners asap

[Joeyprix]

Originally Posted by grandprixgtx00

I would be careful with what additives you use. I personally recommend using Seafoam. Works wonders.

How many miles are on this GP? How long has it been since a tune-up? Any CEL?? As suggested above, maybe try unplugging the MAF and see if it runs better.

IT HAS 177,000 on it and is it ok to run your car without the maf or is that a way o determine if it is a problem with the maf sensor ?

[tblake]

If you unplug your MAF sensor and your problems go away, your MAF is bad. ZZP looks like they have GM ones back in stock in their electronics section at half the price of a new one at the dealer.

I ran with mine unplugged for a couple weeks while I waited for my replacement to be shipped.

[grandprixgtx00]

As Tim said, yes, it is ok to run with your MAF unplugged. You may notice a decrease in gas mileage, and the car may run a bit rough until getting up to running temp. I wouldn't suggest running without one for an extented period of time however of course.

i could not remeove the maf sensor due to lack of propper tools

you don't want to remove the MAF, just unplug it. If the car runs better after unplugging it, then worry about being able to remove it.

[richtazz]

If it does need to be replaced, it requires a T-20 tamper-proof torx bit to remove, just so you know what you need to get.

[Joeyprix]

Originally Posted by richtazz

If it does need to be replaced, it requires a T-20 tamper-proof torx bit to remove, just so you know what you need to get.

thanks for leeting me know hwat tool to get. Im not sure about the second part tho ?

[Joeyprix]

Since i have cleaned the idle air control valve with a clan cloth it has been running better although it still has done the whole idle jumping thing but not near as much. Im wondering if I cleaned that with the air intake cleaner an also got the tool to take the maf off and clean around it also if that may be what i need to do where it has been acting much better ?

[olopezm]

Just UNPLUG the connector to the MAF and see if the RPM cycling is gone. If it does then get the MAF cleaner and the T-20 torx bit, remove the MAF and clean it. DO NOT TOUCH IT. Re-install it and see if the RPM problem is gone.

Best regards,

Oscar.

[Joeyprix]

Oscar someone told me that the maf sensor is just a wire an that it cant really be cleaned but rather needs to be replaced but i have also been running my grand prix without it for a day or so now and it runs jus the same but i do intend to replace it with a second hand one for now and see if i can fix this problem .

[rlamppa1]

Mine acted the same way. I had a bad fuel pressure regulator. When my MAF went bad, I got the check engine light to come on.

[Joeyprix]

My check engine light was on when i bought the car but i have recently unplugged my maf now with you saying about the fuel regulator im wondering could it be that. how much did it cost you to replace it ?

[olopezm]

Originally Posted by Joeyprix

Oscar someone told me that the maf sensor is just a wire an that it cant really be cleaned but rather needs to be replaced but i have also been running my grand prix without it for a day or so now and it runs jus the same but i do intend to replace it with a second hand one for now and see if i can fix this problem .

It's not like that, there are different types of sensors, either way I haven't heard of anybody who advises to touch the sensing element. No user in the forum would do so but I guess it's up to you how you clean it. If the engine ran the same when you unplugged it, then you don't need to replace the MAF.

Originally Posted by rlamppa1

Mine acted the same way. I had a bad fuel pressure regulator. When my MAF went bad, I got the check engine light to come on.

To test the FPR fisrt look for any fuel dripping out of the vacuum hose attached to it. As a second step connect a fuel pressure gauge to the test port, start the engine and see if the pressure reading goes up when you disconnect the vacuum hose form the FPR.

Best regards,

Oscar.