automotive mystery, any help would be appreciated

[roosterjuicer]

my friend has a 2004 pontiac grand prix with the 3800 v6. he says it has been hesitating slightly whenver he hammers on it. i drove it and i noticed a slight hesitation.

he's an idiot and thought he accidently drained his transmission when he was changing his motor, but no fluid came up...and yet he continued driving it. besides this stupidity, upon looking over it briefly, it seems like its in good shape and has 60,000 miles approximately.

i checked the transmission and the fluid is beautiful and was well within the operating range. i checked the bolt he took out when he thought he accidently drained it and it wasn't the drain plug at all, but rather one of the bolts holding the thing together. no leaks or anything. so i think tranny issues are out. the air filter was clean. spark plugs are 100,000 mile spark plugs and all the wires leading to them were in order. the check engine light is not on.

the only thing i could think of was maybe a fuel filter which he says he has not replaced since he bought the car at 30,000 miles. however, he says the thing starts up fine.

im gonna put a new fuel filter on it this weekend. anyone have any other things i should look at or any other theories?

it is the middle of winter and it hasn't gotten above freezing in a while.

[Rockefella]

Oxygen Sensor?

[roosterjuicer]

wouldn't that make the check engine light come on?

[Rockefella]

wouldn't that make the check engine light come on?

Yeah, most likely. I forgot about the 'check engine light isn't on' part.

[johnnynumfiv]

Did you check the tranny fluid while the car was running and in park? Also, where is the fuel filter located?
It sounds like a weird problem. Although it could be just cause it's a 5 year old pontiac. All the modern ones(ranging from a few years old to mid 90s) I've worked on and driven run like complete shit. I think if it was something serious it'd throw a code for running to lean, knocking, etc. Do you have access to a obd2 scanner/computer?

[roosterjuicer]

Did you check the tranny fluid while the car was running and in park? Also, where is the fuel filter located?
It sounds like a weird problem. Although it could be just cause it's a 5 year old pontiac. All the modern ones(ranging from a few years old to mid 90s) I've worked on and driven run like complete shit. I think if it was something serious it'd throw a code for running to lean, knocking, etc. Do you have access to a obd2 scanner/computer?

Yes it was running and in park when i checked it.

i dont have direct access, but i suppose i could go down to o'rieleys and use theirs. but would any codes come up without a check engine light coming on?

[johnnynumfiv]

Yes it was running and in park when i checked it.

i dont have direct access, but i suppose i could go down to o'rieleys and use theirs. but would any codes come up without a check engine light coming on?

Good. A lot of people don't know about that.

I don't know how in depth their tools are but if there is no present code, it probably won't read any. With our snap-on tool at the shop you can check pretty much every reading from every sensor on the car, it helps to figure out whats wrong with the car. You can also see if any codes have been present in the past.

Let us know how it is after the fuel filter change. Hopefully its not an in-tank one.

[roosterjuicer]

Good. A lot of people don't know about that.

I don't know how in depth their tools are but if there is no present code, it probably won't read any. With our snap-on tool at the shop you can check pretty much every reading from every sensor on the car, it helps to figure out whats wrong with the car. You can also see if any codes have been present in the past.

Let us know how it is after the fuel filter change. Hopefully its not an in-tank one.

haha no kidding about the fuel filter. its an in-line (for lack of a better term) deal about a foot and a half in front of the driver side rear tire.

those snap-on computer deals are sweet. my mechanic/friend dale has one and i was having some fan issues on my camaro and he just plugged that thing in a turned the damn fan on from there with not much more than the push of a button. a little spendy for a hobbyiest like myself though.

[johnnynumfiv]

haha no kidding about the fuel filter. its an in-line (for lack of a better term) deal about a foot and a half in front of the driver side rear tire.

those snap-on computer deals are sweet. my mechanic/friend dale has one and i was having some fan issues on my camaro and he just plugged that thing in a turned the damn fan on from there with not much more than the push of a button. a little spendy for a hobbyiest like myself though.

Oh definitely, I'm glad the shop pays for it. Good to hear it's an in-line, it makes things a lot easier. We just had a Pontiac that a drunk kid crashed, he hit so hard/tumbled so many times, all the doors were ripped off, the roof was peeled off, the trunk lid was ripped off, and the gas tank was a few hundred feet from the car. But his handle of vodka was still intact.

[roosterjuicer]

. But his handle of vodka was still intact.

well those plastic bottles that the good stuff comes in are tough to crack

[johnnynumfiv]

well those plastic bottles that the good stuff comes in are tough to crack

It was glass. Supposedly he drank one before he started driving, went off the road at 100mph, hit a pole and started flipping and tumbling. He had a scratch on his head from the accident.

[drakkie]

Did he put it on the tester yet ? What error code come out of it ?

My suspicions go to the air-mass-meter or the injection systems. He got a aftermarket air filter mounted ? Sometimes these can cause problems.

Saw you checked the fuel filter yet, did you also check the throughput of the fuel pump yet ? If that's ok, check the injection system (what kind does this car have) ?

[roosterjuicer]

Did he put it on the tester yet ? What error code come out of it ?

My suspicions go to the air-mass-meter or the injection systems. He got a aftermarket air filter mounted ? Sometimes these can cause problems.

Saw you checked the fuel filter yet, did you also check the throughput of the fuel pump yet ? If that's ok, check the injection system (what kind does this car have) ?

as i said, no check engine light so i didn't bother putting a tester on it because i dont think it would put out any codes without a check engine light.

the car is completely stock.

i havent really checked the fuel filter, i just found it and promised to replace it later. no i havent checked the throughput of the fuel pump. its just a 3800 so i assume its just sequential port injection.

[johnnynumfiv]

Any update?

[roosterjuicer]

yeah apparently i have the magic touch haha. he says its not doing it anymore we never did the fuel filter or anything like that. cars are weird sometimes.