So I was at work today talking to a dodge mechanic that came in about my truck and the plenum gasket. He told me to spray some brake cleaner down the edges of the intake manifold to check for a rise in rpms. I have heard of this with carb cleaner to look for vacuum leaks, which this is, but it doesnt seem like it could really get down to the problem area. Im just wondering if anyone has tried this and if it works. He claims it does, "just dont have a bad plug wire" he said, "good chance of fire" lol.

 

I've never heard of that before. Seems kinda risky. If you have a dodge...then you have or will have a blown plenum gasket. Looking down the TB will tell you if you have a leak if you see oil

 

This might tell you if you have a intake manifold gasket leak, but I dont see how it would tell you if your plenum is blown. The tell tale sign of a blown plenum gasket is A)Losing oil (without leaking oil) B)Burning oil C)Look down your throttle body for oil pooling D)Take the tb off and look in your intake for oil pooling or E)You have a 2nd gen, so your plenum is blown. Take your pick

 

Yeah i know all the regular stuff, just didnt see this working, Im sure my plenum is fine, i have no oil loss anywhere, no pinging, no oil in the intake anywhere, I checked the oil level before i changed it last weekend and it didnt move anywhere, but im still doing the hughs fix eventually just as a preventitive measure

 

spraying anything around the external side of the engine will not show a leaking plenum. plenum sucks air/oil in from the lifter valley.

 

that was my thought also, i just wanted some other input on this test from ppl that have been there, not a salesman mechanic

 

BUMP
i'm there right now...i bought my truck and it had been well maintained and was(still is) mechanically sound (no oil issues)...plus it had a few mods lift kit,solid rebuilt tranny w/cooler, exhaust & a few cosmetic toys...
question is, how can i tell if the plenum has already been done without pulling the engine apart??? lost contact for the prev. owner too.

 

easiest way to test if you have a blown plenum gasket is to look at the emblem on your doors. If they say 'V8 MAGNUM', it's shot.

 

Yep what he said

 

Yah I'm getting kinda tired of hearing E....If the op is like me he bought the truck used and theres a good chance its already been fixed...my plenum is fine and I have 140k on the truck....I know another guy out by my cabin with a 96 who has never touched his and he has 120k and it doesnt burn oil so.... the whole joke about assuming can be true...for example I had a lot of stuff go wrong with my truck shortly after i bought it I join here and find all these people with the same common issues....does that mean I can assume all second gens are lemons??....no thats silly...just most (Im kidding to make a point)

I read a thread here yesterday where a guy took off his throttlebody and found no oil in his throttlebody and also stated he wasnt burning any oil....and right away everyone here was quick to tell him its blown anyway and to change it....so which is it? the sad fact is not every shortcomming on these engines is from a blown plenum gasket.... and the other thing that goes unmentioned here often is the largest contributing factor to the blown plenum is the fact that the bolts holding the plenum plate sandwiching the gasket were too long from the factory and everyone here you has actually just changed out the bolts to the proper length when replacing the gasket have never come back to report a failure afterward. Including one guy here who runs a garage and have done this many times....everyone insists its caused by expanding and contracting rates of different metals used and an aftermarket overpriced plate is needed (steel against aluminum) if that were true most head gaskets would have failed on most new motors with aluminum heads right?