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3800 w/supercharger reliability

I have the opportunity to purchase a well-cared for '99 Grand Prix GTP. I am a bit unsure on a couple of fronts: first, is there any data (anecdotal or otherwise) on the reliability of the supercharged engine vs. the base 3.8? I put lots of miles on my cars (my current daily driver is a '93 Bonneville with 165K and I need this one to go a similar distance). What are the known failure points (and associated repair costs) for this engine?

Also, this model year "requires" premium fuel (though later GTPs do not). Is there a substantive difference between the two engines? Is this a technical requirement (that is, will 87 octane knock or cause other problems) or a legal one (to claim horsepower numbers or some such)?

Thanks for any informed commentary.

JGM

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JGM
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I (we) have a 94 SSEi, supercharged. It currently has 180,000 miles on it. I use Valvoline Synthetic oil. Did a compression test at about 150,000 miles, don't remember the nos. but it was like new. As for the supercharger, I did add a little oil to it once. No other problems with the supercharger. The dealer seems to want to blame other problems on the supercharger though, such as a miss. Plugs and wires have been changed two times. I've had to replace one injector and one coil on the coil pack. Had the transmission seviced at about 75,000 miles and again at 130,000. I am having trouble right now with radiator fan not running and AC not working properly, I believe these problems are related to the computer, but I may have to take it to the dealer to confirm. I do most of the work on my vehicles myself, and take it to the dealer if I need help diagnosing a problem.

Reply to
Jeff & Carol

Almost a year ago, I bought a '99 GTP with 90,000 miles. Before I bought it, a friend of mine who is a GM mechanic performed a computer diagnostic on it and everything seemed fine. Within the next couple of days, I'll be hitting the 100,000 mile mark. So far, I haven't had a single problem with the car. I've just done normal maintenance, nothing special and I've run premium fuel as recommended.

Reply to
Dave

Oh, I've driven it. My main worry is that it's too much fun, especially with some relatively new drivers in the household, to last.

I very much appreciate all the posts. I started out worried about the reliability of the supercharger itself and now I'm paranoid about the plastic intake manifold problems described in another thread. I maintain the cars well and don't mind wear and tear expenses but dread those thousand-dollar-plus type failures that seem to plague most GM cars at 100K or so (many of the 3.8s being notable exceptions). I guess I'll have to accept this risk and the need to buy the premium fuel as the price of admission, though.

JGM

Reply to
JGM

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