I have a 2001 1500 with the 5.2. I'm pretty sure I need a plenum gasket, I see oil in the intake through the throttle body but here's my question. I'm fouling plugs about every 5-6000 miles but just 3 of them. They have oil on them when I pull them out, the other five look to be in good shape.

The engine has 200K on it but runs good with new plugs. Could the plenum gasket just be fouling the 3 plugs? I'm not sure it's the same 3 every time or if it is 3 every time. I just noticed the oil when I changed the plugs yesterday.

I'm going to do a compression check as soon as I can find a gauge, what should the compression be?

 

If you have oil in the plenum, then you definitely need to fix that first. Do you have serious oil consumption problems? (mine was going thru roughly three quarts a WEEK, and it gets driven less than 100 miles in week......)

Real possibility that the plenum is the major contributor to fouled plugs. Compression test won't tell you how good your oil control rings are though.... As for the test itself, anything over 100 pounds is considered 'acceptable'.... all cylinders should be within 25% of each other. (which seems like a LOT of variance to me......)

 

Are these plugs toward the rear of the engine? Oil was gooping up my number 8 plug where I would get a really bad miss. I had to pull it out, clean it, and swap it with another plug every other week or so. Fixed the plenum and no more issue with that.

 

Yes, the plugs are at the rear of the engine. The engine also feels like it's running under a strain now too. I've started to notice some oil burning but not sure how much yet, I keep check on it though.

I'll change the plenum first. I'm ordering the hughes gasket kit, that's pretty much a permanent fix to the plenum problem isn't it?

http://www.hughesengines.com/Index/p...p?partid=26190

 

It's been noted that usually the rear plugs go first when it is a plenum leak. Yes it is a permanent fix. I have only heard of 2 people having a plenum leak after installing the hughes kit, but the oil they saw in their manifold could have been from a faulty PVC valve (which you may also want to check into). I have had the hughes kit in my manifold for over a year now, and no oil consumption, or goobered up plugs.

 

And don't use the PCV valve from the parts store.... I made that mistake, and my oil consumption got WORSE, even after the plenum fix. The aftermarket valves seem to have WAY to high of a flow rate, so, you suck oil right out of the valve covers. Get the valve from the dealer. Ended my insect-fogger-like behavior.

 

Your losing power because the blown plenum has destroyed the cat too. It needs replacing as well as both o2's.

 

Well I've ordered the plenum gasket, I have noticed my PCV valve is rattling a lot too. I replaced it with one from the parts store last time, I'll get one from the dealer today.

I'll also have the cats checked as well.

Thanks for the help guys.