GM 3.1 SFI--Intake manifold gasket ALWAYS go bad? (considering cancelling deal on '95 Century)

Hi folks, I posted yesterday re. buying a '95 Buick Century wagon. 3.1 SFI, 85k miles, $2500. I've put down a small deposit on the car but haven't paid for it yet.
Some helpful folks on these newsgroups have since told me that the intake manifold gasket tends to go bad on these engines, about every 40k-50k miles based on what I read on newsgroup archives.
Should this pretty much be expected of almost every GM vehicle with this engine? It's a $500-$800 job from what I read. The car's seller is a very honest retiree who bought the car with 66k miles 3 years ago from a Cadillac dealer, and he himself has not had problems with the car (I completely believe him).
The '87 Chevy Celebrity it would be replacing is very rusty, but the 2.8 MFI in our Chevy has never given us any trouble. I figured that the 3.1 SFIs would be as good, but I'm starting to have doubts.
(if these engines always need a $500-$800 repair every 40k-50k miles, then it would seem almost as much of a gamble as buying a Ford Taurus wagon of the same vintage and keeping my fingers crossed about the transmission!)
Any/all thoughts greatly appreciated. My positive experiences with the Chevy 2.8 encouraged me to look for another GM product, but I just want to make sure that I'm not looking an an engine that's generally considered inferior...
Pulling my hair out now, John
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I think it's the luck of the draw. The 3100 I have in my 94 Grand Prix has 150k on it, and does just fine.

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<snip>

John,
The primary cause of intake manifold failure in these vehicles is a backfire in the intake manifold. The likely hood of this happening can be significantly reduced by having the vehicle powertrain control module 'reflashed' with the current version of software. GM is well aware of this issue and has had a fix out for almost a year.

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"saeengineer" wrote
The primary cause of intake manifold failure in these vehicles is a backfire in the intake manifold. The likely hood of this happening can be significantly reduced by having the vehicle powertrain control module 'reflashed' with the current version of software. GM is well aware of this issue and has had a fix out for almost a year.
Wrong engine....and even on the right engine.....the backfiring is "not" the primary cause of intake manifold problems. The 3800 has far more intake problems caused by the EGR pipe in the lower manifold then it has problems with the backfiring issue. The OP's engine is a 3.1 v-6.
Ian
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snipped-for-privacy@caregroup.harvard.edu (John Yang, MD) wrote in message

<snip>
A few months ago, the man who delivers parts to our shop brought out a flier that was advertising an aftermarket intake manifold for these engines (I believe) that was made by Dorman. For those of you who have not heard of Dorman, they make a lot of small parts such as nuts, bolts, washers and the like. Anyway, in their flier, they were touting all the benefits of their manifold and how their design was so much better than the factory and how you would never have any problems when using their new manifold. First, I was surprised that they were making this manifold because it seemed like a completely new line for them. Now, has anybody used this aftermarket manifold? I'm curious how well they've done their homework........
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snipped-for-privacy@caregroup.harvard.edu (John Yang, MD) wrote in message

<snip>
Forgive me if this is posted twice. Anyway, a few months ago, our parts supplier threw in an ad for an aftermarket intake manifold for these engines that supposedly eliminates all intake manifold sealing problems. It was an ad from Dorman. The suprise is that Dorman is a supplier of small parts, such as washers, bolts, nuts and small specialty items. The ad showed the intake and all the benefits it had that eliminates all sealing problems. Anyone used this yet? I have not seen any details on this intake and our parts supplier has yet to order or sell one of these. Any comments from you Dorman suppliers? Surely if one aftermarket company is selling this intake manifold, others will follow.....
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Well, you might get 80K after the 1st repair. I've had 3 mini-vans....different years 1990 - 1992 -1994 all had the same problem. Plus two had the "o" ring problem. Fortunately, I've learned how to do the job myself.
Nicest thing about GM... they have catastrophic problems acrross several engine lines...I bought a 2002 with a 3.4 Engine...which I'm expecting the lower intake manifold gasket leak any week now (soon as it gets out of warranty).
My friend has the GM 3800 with the plastic intake plenum. 1994 Buick Regal with about 20K miles... No signs of warpage yet. It'll happen.... no doubt in my mind.
And I won't mention about the Alternator's which need replacing every 50 - 80K miles. (I did one on a friends car at 20K miles, but the car was 10 years old and rarely driven. Unfortunately the alternators are NOT a DIY bench job although it takes just a few minutes to swap them out of the car. DIY about 80 - 120. A mechanic charges about 200 - 250 plus finds a lot of other defective things in the process.
For comparision a friend has a Honda Civic 1988 150,000 K miles... engine runs great but the body had rust spots... She sold it and the new buyer did some body work and uses the car for a daily commute.
Here's a success story....Another friend owns a 1990 Honda 190,000.... never touched the engine, (Well he replaced the plugs at 190,000 and an O2 sensor. Minimum maintenance and uses the car for a daily commute.
If I were looking for reliable transportation, I would probably buy a Honda (which is assembled in America). For me a mini-van is a necessity..... thankfully I can repair most of the problems. I can even accept design flaws as a fact of life.... but, when I wake up and face reality. GM quality across it's product lines leaves a LOT to be desired. ( I'm still buying GM... all of my FORD products..sucked BIG TIME... Maybe someday I'll own a Honda provided they do something about that UGLY lack of styling.
You pays you money, and you takes you chances....
On 30 Nov 2003 23:09:01 -0800, snipped-for-privacy@caregroup.harvard.edu (John Yang, MD) wrote:

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