Thread: 06 Grand prix GXP rev/misfire issue???

So I just bought a 06 gxp with 91,000 miles and had a code for oil pressure sending unit. Went to autozone and replaced the sensor and code went away. Now I have this odd rpm rev happening. ill be driving on the highway at a constant 70mph and the rpms will go up a couple hundred like your tapping the gas. this happens on cruise and in town at slower speeds too. So I went back and got a new oil sensor to give that a shot...the revving issue disappeared....till I had it parked a few hours and fired it up later that day. issue popped back up. I figure it has something to do with that oil sensor but not positive. started happening when I changed the sensor the first time and now I have this problem.... no idea whats happening and I cannot find anybody else that has a similar issue. Hope someone has some advice/information.

Originally Posted by Derickgxp

So I just bought a 06 gxp with 91,000 miles and had a code for oil pressure sending unit. Went to autozone and replaced the sensor and code went away. Now I have this odd rpm rev happening. ill be driving on the highway at a constant 70mph and the rpms will go up a couple hundred like your tapping the gas. this happens on cruise and in town at slower speeds too. So I went back and got a new oil sensor to give that a shot...the revving issue disappeared....till I had it parked a few hours and fired it up later that day. issue popped back up. I figure it has something to do with that oil sensor but not positive. started happening when I changed the sensor the first time and now I have this problem.... no idea whats happening and I cannot find anybody else that has a similar issue. Hope someone has some advice/information.

Sounds like the first stages of trans failure...

yea that's funny cause thats what I thought too because we had a tcc code also. long story short got screwed when I bought the vehicle. had codes for trans, wheel bearing, and oil pressure sending unit. Just got it back from the tranny shop today cause it was shifting horrible the day after we bought it. Luckily i purchased the 24,000 mile warranty with it so it was fixed farely easily. but trans has been rebuilt and shifts like a dream. so got the new oil sensor today and the rpm issue went away for a little then came back. I was pissed at first cause I figured it was still the trans but im 99% sure its not.

Well, the TCC is what sounds like is kicking the RPMs up and down...which usually on these is the sign the trans is getting ready to go.

Yea I had a 99 grand prix that threw the tcc code so I pulled the side cover off and replaced the 3 solenoids right there and never had a problem after that. maybe still could be a problem with a solenoid. but no codes so far and tranny shifts flawless. Going to take it to the local transmission shop Monday and have them scan it. but how it came after the first oil sensor then went away for a little bit after the second oil sensor confuses me.

Coincidence.

The tranny now has a 12 month/12,000 mile warranty so that's the good part but im tired of this thing being in the shop and I have only had it 3 weeks. I have worked on many of my own grand prixs doing top swaps motor swaps and all that but this was all warranted so there was no way I was working on a brand new(used) car I just purchased when I have insurance to cover it all.

Yeah, I'd take it and get it done right. No reason for a car with that kind of mileage to be having these issues anyway unless it was beat.

the shop that did the transmission definitely would not have been my first choice but the insurance selected it. So im not gonna say they rebuilt everything 100% but I will find out Monday because the shop im taking it too is only a transmission shop so they have all the bad ass scanners that tell them everything that's going on inside the tranny.

Well, a scanner will give them an idea. Make sure you give them every ounce of information you can so they can get it diagnosed right the first time. Like "When I'm travelling at _______MPH on incline/flat road/etc with my cruise on/steady throttle my trans does ____________"

Yea definitely. It still being the trans is not what I wanted to hear but kind of figured because it feels exactly like the torque converter acting up. Guess ill find out Monday.

I wish you the best bud.

Thanks man I appreciate the help.

No problem. We're all here for a common cause.

yes I know exactly what your saying. this guy said he did a whole list of stuff, a rebuild kit, valve body, torque converter and some other things that im not sure if there even in a tranny lol. like I said it wouldn't have been the first place I would have chose. but yea I'm thinking he figured all sensors or whatever was good and didn't mess with them. like u said fixed the obvious broken things.

Originally Posted by 91parkave

Your oilpressure directly affects your dod system Which is why you're having these sympoms . take it in have a tech drive it with a scan tool and proceed from there. Don't automatically assume its a trans issue

This I didn't know. Learn something new every day. Thank you 91parkave!