Plastic Intake Gasket Problems

[91GranSport]

Has anyone ever experienced problems with their plastic intakes on 3100 SFIs, 3.1L MPFIs, 3400 SFIs, etc? I have a 3800 TPI and the intake is aluminum and the runners are cast iron. I think '93+ were plastic. Anyways, here's a site I came across...

 

http://www.gm-v6lemons.com/

 

Strangely I haven't heard of anyone having this problem before.

[Chris A]

Surprising you haven't heard of bad intake gaskets on a 3.1 2.8 3.4 etc. Its quite common for them to leak internally through the gasket into the engine. Typically if this isn't caught soon enough it can take out the engine as the crankcase fills with water. The business with it taking out the cam might be true, but not neccesarily because of dexcool. Any water in the engine could cause serious problems. The "plastic" he refers to is the actual gasket, not the intake itself. They are cast plastic gaskets with oring seals in them. The plastic cracks over time and leaks. FWIW, i've seen this happen on many cars of different makes with plastic gaskets. THe gaskets are nice because they do a good job of sealing initially. However, they can shift over time and crack.

 

I can understand this guy being upset. But he's the kind of guy that burns bridges. He buys two USED cars from a dealership. The second develops a problem that he himself claims is COMMON. The dealership while being empathetic won't do anything to fix the problem. Why should they? He bougth a USED car!!!

 

Second his reasonings are weak. The gaskets are on back order so that means its such a chronic problem GM should recognize it? How long did it take Ford to admit the 3.8 had a headgasket problem? Good luck on a CA lawsuit. The last CA (class action) against GM resulted in crappy payouts for the end consumer (wbody brake litigation).

[Steve LS]

Heres a link to a discussion about this on the 3800 .

 

http://discussions.gmforums.com/showthread.php?s=23b30c663e6f039b3bcb93833d134abe&threadid=27788

[Steve LS]

Heres a link to a discussion about this on the 3800 .

 

http://discussions.gmforums.com/showthread.php?s=23b30c663e6f039b3bcb93833d134abe&threadid=27788

 

I wanted to ad - Chris A I do understand what you mean about buying a used car. But this is a manufacturing defect of even engineering fault. Because the original owner didnt drive the vehical long enough for the problem to show up doesnt mean the poor unsuspecting fool buying a excellent used car for serious money should have to eat a entire expensive engine job. This is not normal ware and tare were talking about here. Its a sleeping lion.

 

My example : I bought our 97 LSS L67 with 60,000 miles on it. It was a original owner trade in, and I bought it from a Oldsmobile, Cadillac dealer.It did and still does run ,look, drive and ride like a almost new car. So I decided I would finance nearly 10,000 dollars for four years for the car. Now if this problem awakens before I have it paid for and say it gets the engine. I may be scrambling to figure out how to afford the repair. The engine and car is still in great shape ware wise but due to some engineering or penny pinching executive decision to start to make engine parts out of plastic I should have to eat it ?

 

I have stuck with cars with the Buick V6 because I'm fimilar with it and it has a reputation for being tough and high milage. I new nothing of this plastic parts business untill this post. My fault for not being more read of informed ? I think not , I'm pretty busy taking care of other important stuff surrounding my daily life and figured I new enough about the 90 degree V6.

 

Everyone knows plastic shrinks ,warps and becomes brittle and even eventually turns into gue or dust. Thats why all our window weather stripping becomes 2" to short after 4 years. Or many other things us common folks have seen happen to plastic over our life times. SO WHY THEN WOULD SOME HIGHLY SCHOOLED & PAID ENGINEER decide it would be OK inside or on a engine. I remember around 10 years ago or so seeing a program on why new cars were now so expensive and it was all about how they were now using higher quality alloys all through out a car. What kinda alloy is this manifold ?

 

This is a factory delivered defect. Though the percentage of awakening may be low the ones it happens to should not have their financial lives compromised due to some penny pinching by a "cant see it from my house" rich executive. Anyone buy a excellent clean used GM product is doing so in good faith and knowledge that it is a quality engineered and built vehicle . Its not like your being cheap and buying a Yugo.

[91GranSport]

Say, while we're on the topic, is it possible to replace those plastic intake manifold gaskets with cork or rubber gaskets?