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2004 Grand Prix GTP (SC)---Diagnosis help.

razorx92

New member
Car Specifications:
2004 Grand Prix GTP (Supercharged)
3.8L SC
93,600 Miles.

Im sick of playing guessing games with the shop. First they told me my transmission needed to be flushed. During the flushing they said to check if I see any shavings. I found nothing while watching the garage do the flush. After this flush, my shifting improved, but thats about it. Any ideas of what I should have checked or maybe even what the problem may be? This car has been named "Pegasus" because it seems impossible to figure out the issue. I will say that I have a hunch that im slowly saying good bye to my transmission, but im not about to spend a ton of money unless someone else can back that idea up. Also, anyone know if this is a common issue with these cars?

Problem:
1.) Weird Grinding/ Vibration coming from the front towards the center of the dashboard on the floor.
2.) Sounds and feels like misfiring (NO CHECK ENGINE LIGHT)
3.) Start up, runs perfectly for 5 seconds, then bogs down and almost stalls, then resumes perfect running (intermittent issue)
4.) ONLY WHEN TURNING, sometimes the car will rev high without accelerating to match. Then out of nowhere a big burst of power (intermittent issue)

Known Issues:
1.) Strut mount in the front = Binding (Probably not related to the above)
2.) Needs a brake job. (Rotors are very shot. aswell as the pads, not sure about calipers....)

What I've Fixed while trying to figure this out (everything fixed has been suggested by a garage, but done by me, except whats specified.)

1.) Spark Plugs and Wires
2.) Transmission Flush (Done by Sears)
3.) Left Wheel Bearing (This was to remedy the issue of my ABS acting up. Remedy was a success)
4.) Replaced 02 sensors
5.) Replaced catalytic converter


What the "pros" think it is:
1.) BOTH CV Shafts.
2.) Wheel Bearings (CV Shaft Slipping)
 


The fluid is perfect. all fluids are, actually. Ill check the sensors you guys have mentioned and report back. So, what are the chances it could be a CV Shaft?
 
any access to a good scanner, (watch misfire count)

Don't look for a IAC valve. Its drive by wire which is why joe said to clean your TB
 
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Just one more thing to add to this anomaly.... Not throwing a single code. I haven't had time to get those things checked yet, can i clean any of that stuff myself? I'll be flat out, i know just about nothing when it comes to the engine of a car, but if you ask me about installing lighting, sound and other equipment, i can do that with my eyes closed. haha. Its a alittle backwards i know :th_biggrin2:
 
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