..G.M. 60o 3.1,,3.4 from 1998 to end of run are prone to intake gasket failure,there is a HIGH gasket failure,,I have just learn that this has resulted in destroyed engines.if your 3.4 hasover 60,000 miles or you do not know if it has been replaced. It is a good idea to check your oil weekly on all/any 3.1 & 3.4 engines ..The original gasket was a plastic looking material with a record of failure.the G.M. new improved gasket sucks ,,make sure you recieve the metal(steel gasket) with rubber inserts.fel pro ,ect. also there are still old style gaskets around,get the latest steel gasket ..I have never done this job ,my post is promted by listening to a man on a mechanic talk show whose engine destroyed itself,just a heads up ,im sure this has been reported on before ..there are many post about this on the internet,watch one of the videos, then use photos on d-tips.com ..this job will cost $350 to $500 to have a garage do it,, this is not a simple job,but with internet can be done ..Newbie use lisle tool to prevent damage to aluminum heads $16 to $20 there are many many articles on the internet about this
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02:13 PM
PFF
System Bot
Blacktree Member
Posts: 20770 From: Central Florida Registered: Dec 2001
Just to clarify, the gasket in question is the one between the lower intake manifold and the cylinder heads. And the engines in question are the 3100 and 3400 SFI V6, which were used in lots of GM FWD cars and minivans.
The typical failure mode allows coolant to leak into the intake ports and/or the crankcase. If the coolant leaks into an intake port, you will have steam coming out of the exhaust. And if the leak is bad enough, it can hydro-lock one of the pistons. If it's leaking into the crankcase, coolant will mix with the engine oil and trash the engine bearings.
This is a pretty common and well-known problem. But not everybody is "in the know". So repeating the information can't hurt.
Oddly enough, the 3800 V6 has a similar problem.
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03:04 PM
ericjon262 Member
Posts: 3135 From: everywhere. Registered: Jan 2010
GM recalled 1.5 million vehicles with this engine on April 14, 2009 due to risk of fire from engine oil leaking under the valve cover gaskets onto hot exhaust manifolds. The fire could spread to the nearby plastic spark plug wire retainers on the valve cover and then to the rest of the engine compartment. GM fitted the affected vehicles with redesigned spark plug wire retainers.[3] These engines were noted for having problems with the plastic upper intake manifold cracking around the EGR passage. The engine would then vapor lock. The lower intake gaskets and upper intake manifolds were revised, correcting all these issues.
3100/3400-
quote
From the mid-1990s to 2003 these engines had failure prone intake manifold gaskets which could cause coolant leakage often leading to engine failure. A series of class action lawsuits, implicating deterioration of the nylon/silicone material of the gasket are pending on this issue. Tell-tale signs of such eventual related damage are a white foam that appears on the inside of the oil filler cap and the gradually increasing loss of antifreeze coolant (due to seepage into the intake passages which will lead to engine lock up failure in such cases). External seepage is also found near the valley edge of the lower intake manifold.
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03:41 PM
1fatcat Member
Posts: 1519 From: Zimmerman, Mn Registered: Dec 2010
This problem is common on any engine that used plastic framed gaskets. It's been a problem since the early 90's with the 3.1L. It's a problem with the 3.1, the 3.4, the 3.8, the 4.8, the 5.3, the 6.0 and probably a few others.
Plastic framed gaskets suck, no matter who made the engine (GM, Ford, Chrysler, imports, ect, ect, ect).
Always use a metal framed gasket to replace them when/if available.
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11:10 PM
Feb 20th, 2012
ericjon262 Member
Posts: 3135 From: everywhere. Registered: Jan 2010
GM recalled 1.5 million vehicles with this engine on April 14, 2009 due to risk of fire from engine oil leaking under the valve cover gaskets onto hot exhaust manifolds, and because 3800's suck. The fire could spread to the nearby plastic spark plug wire retainers on the valve cover and then to the rest of the engine compartment. GM fitted the affected vehicles with redesigned spark plug wire retainers.[3] These engines were noted for having problems with the plastic upper intake manifold cracking around the EGR passage. The engine would then vapor lock. The lower intake gaskets and upper intake manifolds were revised, correcting all these issues.
See matt, the problem with wikipedia is that anyone can edit it like I just did...
------------------ there's a Group on 60degreeV6.com for us 660 Fiero owners!
This is ALL 3.1 & 3.4 there were a lot of bad aftermarket gaskets installed on 3.4 and 3.8 the worst are the later 3.1 & 3.4. but all 3.1,,3.4,,3.8 are suspect,,not because of leak,s but because your engine could lock up or water/coolant in cylinder could bend rod. faulty plastic gaskets were installed on earlier models at replacement time any hint of trouble,, replace
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03:05 PM
jaskispyder Member
Posts: 21510 From: Northern MI Registered: Jun 2002
This is ALL 3.1 & 3.4 there were a lot of bad aftermarket gaskets installed on 3.4 and 3.8 the worst are the later 3.1 & 3.4. but all 3.1,,3.4,,3.8 are suspect,,not because of leak,s but because your engine could lock up or water/coolant in cylinder could bend rod. faulty plastic gaskets were installed on earlier models at replacement time any hint of trouble,, replace
The the main factory culprits are the 3100, 3400... the Gen I and Gen II 60* engines didn't really have an issue with the LIM as they have completely different gaskets than the Gen III engines. The 3500 still has a questionable gasket but the issues of proper installation were much better understood at that point.
The real issue with the lower intake manifold gasket is that it was weak and improper torque application caused the gasket to distort or break during install but it would go unnoticed.
Fel-Pro has a problem solver gasket that eliminates the issue with a metal and rubber gasket. FEL-PRO Kit Part # MS98003T
Really? Who cares, I bet you it was removed within seconds. They do not let you edit more important articles like Obama and the like without some big permission.
I WILL continue to cite Wikipedia as a source, that will not stop me, ever.
[This message has been edited by mattwa (edited 02-20-2012).]
Really? Who cares, I bet you it was removed within seconds. They do not let you edit more important articles like Obama and the like without some big permission.
I WILL continue to cite Wikipedia as a source, that will not stop me, ever.
You're so hard core Matt...
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05:17 PM
ericjon262 Member
Posts: 3135 From: everywhere. Registered: Jan 2010
Really? Who cares, I bet you it was removed within seconds. They do not let you edit more important articles like Obama and the like without some big permission.
I WILL continue to cite Wikipedia as a source, that will not stop me, ever.
it was there for at least 5 hours, just because it says so on the internet doesn't mean it's true, or false!
I'm sure those plastic framed gaskets are crap, but I also believe in the Dex-cool demon. I just haven't seen this problem in vehicles without it. The sh=t gets acidic with age and eats gaskets.
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10:24 PM
Doober Member
Posts: 445 From: Oro Valley, AZ/Swartz Creek, MI USA Registered: Nov 2006
I did this on a friend's '99 3400 Alero... not a job I wanted to repeat so I went with the expensive 'fix it' Fel Pros. His was luckily leaking to the outside of the engine. I also went with these same steel core Fel Pros on my Vortec headed 383... my mom's '99 Suburban (Vortec 350) failed and my dad & I did the steel core gaskets several years back.
I believe everything I read on the internet; Fieros suck.....They all catch fire, they all have Lotus suspension, They're all plastic, they're just a Citation turned backwards.....and, oh yeah- They all suck!
