[rchilcoat]

Yesterday morning my wife tried to start our 2002 Town & Country Limited in the garage. She described an "enormous explosion" from under the hood and smoke exiting the fresh air inlet in front of the windshield.

It sounded like a simple backfire through the throttle body, so I first checked the air filter to see if it was damaged. It was perfect. I then started looking over the induction system to see how smoke could have been exiting where she had indicated. I found that the entire top of the center rear runner of the plastic intake manifold was gone! There was a fist-sized hole in the manifold, with ragged edges around it. Obviously the car was not going to start, so I just called AAA and had it towed to the dealer.

I've never seen an intake manifold damaged by a backfire before (I worked professionally as a mechanic in an earlier life). It's plastic, but it should be able to take a simple backfire.

Have any of you ever seen anything like this? I'm really curious. The car only has 76,000 miles on it. Out of warranty, but I'm thinking about complaining to Chrysler anyway.

Bob

 

[AzTraveller]

One of the guys on the Fuel Saver Forums, blew his manifold in half, literally. He'd left the HHO generator on while going in to Vote. :blink:

When he came back, 2 hours later, He turned the key, and was suddenly the "talk of the parking lot".
:lol:

 

[shipo]

Yesterday morning my wife tried to start our 2002 Town & Country Limited in the garage. She described an "enormous explosion" from under the hood and smoke exiting the fresh air inlet in front of the windshield.

It sounded like a simple backfire through the throttle body, so I first checked the air filter to see if it was damaged. It was perfect. I then started looking over the induction system to see how smoke could have been exiting where she had indicated. I found that the entire top of the center rear runner of the plastic intake manifold was gone! There was a fist-sized hole in the manifold, with ragged edges around it. Obviously the car was not going to start, so I just called AAA and had it towed to the dealer.

I've never seen an intake manifold damaged by a backfire before (I worked professionally as a mechanic in an earlier life). It's plastic, but it should be able to take a simple backfire.

Have any of you ever seen anything like this? I'm really curious. The car only has 76,000 miles on it. Out of warranty, but I'm thinking about complaining to Chrysler anyway.

Bob

I have seen intake backfires serious enough to damage the butterfly valve in a carburetor, and I have little doubt that a backfire event serious enough to do that could easily damage a plastic intake plenum. Based upon the engines I've seen do this, I'd say there's a good chance that you either have a burned intake valve, an intake valve that is sticking partially open, or a bad lifter that isn't allowing its valve to completely close.

Keep us posted on what you find.

 

[Hokiefyd]

On GM engines with plastic intake manifolds (like the plastic uppers on ours), there is a backfire blowoff valve on the intake that pops out in the case of a backfire. The valve is sacrificed, but the manifold is saved.

 

[sideburns2009]

On GM engines with plastic intake manifolds (like the plastic uppers on ours), there is a backfire blowoff valve on the intake that pops out in the case of a backfire. The valve is sacrificed, but the manifold is saved.

Same goes with my 97 T&C and the 94. It has a "freeze plug" type thing on the side of the intake manifold(metal one).

 

[paart]

On GM engines with plastic intake manifolds (like the plastic uppers on ours), there is a backfire blowoff valve on the intake that pops out in the case of a backfire. The valve is sacrificed, but the manifold is saved.

That way the cheezy plastic GM manifold can just die a normal death by cracking and leaking like all the others do! :lol:

 

[Organized Confusion]

AWESOME!
glad no one was hurt!

those old Ford Bronco II and Ranger engines used to do that when the fuel pressure regulator check ball would get stuck and fill up the intake with fuel and blow the intake and hoods off of them from what I told by a friend who almost got really hurt from his. I have seen an S-10 backfire and destory a metal valve cover

 

[AzTraveller]

On GM engines with plastic intake manifolds (like the plastic uppers on ours), there is a backfire blowoff valve on the intake that pops out in the case of a backfire. The valve is sacrificed, but the manifold is saved.

My brother purchased one similar to these from a "dealer's auction". The vehicle wouldn't start and was pushed through the auction. Got it for a "song", then just had to "re-seat" the spring loaded pop-off valve when he got it to his shop. Started right up, ran fine.
:lol:

 

[IssaquahWA1979]

A friend that I used to work with had this happen to his Ranger back in the 80's and the truck burned to the ground there were flmaes pouring out of the tailpipe he said by the time the thing got going.

AWESOME!
glad no one was hurt!

those old Ford Bronco II and Ranger engines used to do that when the fuel pressure regulator check ball would get stuck and fill up the intake with fuel and blow the intake and hoods off of them from what I told by a friend who almost got really hurt from his. I have seen an S-10 backfire and destory a metal valve cover

 

[Hokiefyd]

That way the cheezy plastic GM manifold can just die a normal death by cracking and leaking like all the others do! :lol:

Huh?? I'm talking about the Northstar/LS1 intake manifold. I've never heard of one of them leaking. I know the ones on the 3800s leak, but that's because they ran coolant through them (unsure why). The ones on the Northstars and LS1s were dry intakes. :thumb:

 

[Hokiefyd]

My brother purchased one similar to these from a "dealer's auction". The vehicle wouldn't start and was pushed through the auction. Got it for a "song", then just had to "re-seat" the spring loaded pop-off valve when he got it to his shop. Started right up, ran fine.
:lol:

Awesome. :ThumbsUp:

 

[sideburns2009]

Huh?? I'm talking about the Northstar/LS1 intake manifold. I've never heard of one of them leaking. I know the ones on the 3800s leak, but that's because they ran coolant through them (unsure why). The ones on the Northstars and LS1s were dry intakes. :thumb:

Yes it was definately the 3800's and the 3100/3400's and also the vortec 4.3 and 5.3 V8. The "almighty" dex-cool coolant that GM "requires" is the culprit...not the gasket as many believed. The Dex-Cool has "plastisizers" in it that eat through plastic/rubber...leading to the intake gasket failing. Get a new GM and flush out the dexcool and replace with good ole green anti-freeze and you won't have a problem.I had a 1996 Oldsmobile Achieva with the 3100. Gaskets among other problems were nightmares. I'll stick with Chrysler.