I own a stock, pristine 87GN with 16k miles on it. I've had the car a few years now (bought from original owner), and have rarely driven it since ownership. While the car is in immaculate condition, it has not run right since I acquired it. Now I'm finally getting around to dedicating some time to it, and sort it out. While I have a lot of car experience, have owned many cars, and worked on many cars, I have to admit I have very little knowledge of these 3.8 SFI Turbo motors, so pardon my ignorance.
The issue my car has had since day one, is not running properly. She does not idle smoothly, she sputters and surges when cruising at a constant speed. Go heavy on the throttle, and the motor seems to run ok however.
Today I just installed the Scanmaster 2.1, so hopefully it will help determine the issues I'm having.
First a bit about the car, and what I've done, checked so far. As far as I can tell, and from what the previous owner told me, the car is 100% stock with the exception that it has a Hypertech 41372 chip installed. Today for the first time, I did verify that it does indeed have this chip installed. Everything else appears to be stock, and untouched.
1. Fresh Amsoil synthetic oil and Filter installed.
2. Fresh set of AC Delco R44TS plugs gaped and installed.
3. Fresh set of AC Delco plug wires installed
4. New Coil Pack installed
5. New AC Delco Air Filter
6. Scanmaster installed today
Changing all of this stuff did not help the running rough issues I have been having.
All of the readings I got off the scanmaster today seem to be normal (I referenced the instruction manual of the scanmaster) with the exception of the timing retard. During several full throttle acceleration runs, I witnessed the timing retard jumped way above the manuals recommended 2-3. It jumped up to double digits range. 11 or so. I'm no expert, but this can't be good.
My intention is to keep this car mostly stock, I may consider doing some slight mod's to it in the future, but right now, my focus is on getting it sorted and running well before I do so.
Please advise.
Thanks, Rob.
The issue my car has had since day one, is not running properly. She does not idle smoothly, she sputters and surges when cruising at a constant speed. Go heavy on the throttle, and the motor seems to run ok however.
Today I just installed the Scanmaster 2.1, so hopefully it will help determine the issues I'm having.
First a bit about the car, and what I've done, checked so far. As far as I can tell, and from what the previous owner told me, the car is 100% stock with the exception that it has a Hypertech 41372 chip installed. Today for the first time, I did verify that it does indeed have this chip installed. Everything else appears to be stock, and untouched.
1. Fresh Amsoil synthetic oil and Filter installed.
2. Fresh set of AC Delco R44TS plugs gaped and installed.
3. Fresh set of AC Delco plug wires installed
4. New Coil Pack installed
5. New AC Delco Air Filter
6. Scanmaster installed today
Changing all of this stuff did not help the running rough issues I have been having.
All of the readings I got off the scanmaster today seem to be normal (I referenced the instruction manual of the scanmaster) with the exception of the timing retard. During several full throttle acceleration runs, I witnessed the timing retard jumped way above the manuals recommended 2-3. It jumped up to double digits range. 11 or so. I'm no expert, but this can't be good.
My intention is to keep this car mostly stock, I may consider doing some slight mod's to it in the future, but right now, my focus is on getting it sorted and running well before I do so.
Please advise.
Thanks, Rob.
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