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Hello everybody! '07 Grand Prix GXP problems...

Brian727

New member
Hi everybody! I'm not completely auto savvy, but I'm learning. I have been having problems with my '07 Grand Prix GXP. 5.3 L V8 140,000 miles. My transmission takes forever to switch gears, I have this clicking sound when I turn ( multiple auto shops have told me that it wasn't my cv axles ), and my engine light is on ( codes : p0443, p0030, p0036 ). Lately the car seems as if it just isn't getting gas, it kind of gets weak then it just takes off. Also I was told by a transmission shop that I was missing engine mounts. How many engine mounts should I have and any diagram available? I replaced the battery with an optima red top because the battery was extremely weak. I have taken it to a mechanic shop and they attempted to fix the transmission but could not prevail. I'm about to buy one from a salvage yard just to replace transmission and extra parts. Salvage yard car engine is in great condition. Could this problem be my fuel pump, oxygen sensor, or is it just my transmission...?

And also, I want to upgrade this car under the hood. Any suggestions? Engine swaps?
And any suggestions of salvage yards that would have this particular vehicle? I know that it wasn't mass produced.
And any ideas on a good double din cd player that would fit?

Sorry to bombard with questions but I'm new to the site and this car. This car has been a major headache but I love the performance from the vehicle along with comfortability. I would like to keep this car but I also don't want to invest over $2000 fixing it. Thank you for your time guys.

-Brian
 
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Well...

You don't want to invest over $2k in repairs, but you're also talking about engine swaps and stereos. You've got to figure out what your priorities are. There's not much else I can think of that would click going through corners, so despite your mechanic saying otherwise, I still think that's what you've got going on.

However, the possible slipping transmission is something you'll want to bring to a transmission specialist to diagnose.

Get those fixed, then start thinking about upgrades.
 
Of course maintenance is my priority. Just throwing questions out there. That should've been a different thread. I apologize but this car has been nothing but problems. Transmission is my main problem. But what about the engine codes? I've had multiple different explanations for the codes. And are you saying that it IS my cv axles making the clicking noise? Putting yourself in my position, what would you do? And my fuel gauge isn't working properly, hence why I was asking about the fuel pump and oxygen sensor. Just looking for some decent opinions here. If you think I should take it to a transmission specialist, what should I know? What should I ask? And any suggestions on a good repair shop? I live in the Tampa/St. Petersburg area of Florida. Thanks guys. And again sorry for asking too much. I just need a variety of advice because I've only been getting a limited amount from asking friends and "specialists"
 
Car wasn't mass produced? Yeah it was it's a grand prix. I'd try a fluid and filter change with a bottle of lucas stop slip in your trans to help it out and a shift kit while you're in there. They might think it's missing a motor mount because the gxp only had one dogbone whereas the v6's had 2.
 
Hop on ls1 tech under the ls4 section contact either x11 nut or 08pimpalass there both in the Florida area where you are and can get you the help you need.

As for your engine codes I would check your fuses and relays. Something isn't right. And it just so happens those wires all run together. As for your engine mounts....replace them ......replace them...replace them. Lower rear and front. They are very weak and tear apart easily with age. Clicking noise might fix itself after you square that away
 


So wait a minute...
@dsmuts
I was told that there was only a limited amount produced of the GXP version. 5.3 L V8 instead of the 3.6 L V6. Along with a different transmission. Hence my questions. I have also done the Lucas stop slip along with a transmission flush. But later was told that Lucas stop slip is horrible for your transmission. Expands seals and makes them tear easier. And you are telling me that I only have one engine mount? But the next guy says I have 2?

@91parkave
I have been told to check the fuses and relays. Any guide on that? Maybe a diagram of what should be there in case I'm missing any. And thank you for the heads up with those guys in the Tampa Bay area. I will get on to that site asap and get in touch with them.
 
There were a limited number but they aren't that rare. The others came with a 3800 btw. I use lucas in everything. You have one up top one on the bottom and one on the trans.
 
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