hey people. first off Sorry for the long post. i wanna make sure im thinking okay, any and all suggestion welcome and wanted.
i picked the truck up a few months back, 147k on it, im happy with it for most part cept the oil consumption/pinging deal. How much oil does it use? Qrt. per tank maybe lil less, i gas at shell usually. 87 oct mostly, i'd like to run mid or premium but at 4.49 for 87 and 4.70 gal for 92 oct. i cant afford too. I realize thats alot of oil being used.
i donot see any smoking while driving, it does sometimes puke smoke upon startup after it has been driven, but thats bout it.

im just trying to get my head around the best way to attack the issue with the least path of resistence and cost.

this is my list from what ive gathered from all u alls posts, Thanks!

1. check the TB for oil seepage, if no oil visible should i be lookin t see if last owner installed reinforcement kit? i should prolly just install reinforcement kit right? seems obvious that im getting fair amount of blowby by amount of oil i go thru!

2. check plugwires, replace plugs, dielectric all. reroute plugwires so not running together (jump spark).

3. fuel additive which to use?

4. seafoam or chemical cleaner down TB to aid in breaking up carbon/gunk build up.

5. slowly pour methanol (windsheild wiper fluid) or cold water down TB to shock remaining gunk off valves heads while still soft from chem. cleaner.

 

It is a blown plenum. Start by reading the "End All Plenum" thread. Your plenum intake gasket is blown. The good news is if you're handy at all, it'll be a weekend project.

 

p.s. There is absolutely no doubt it is anything else. They used a steel plate on the bottom of an aluminum plenum(that big air intake on top of the engine). The differing heat dissipation characteristics of the 2 metals+probably a bad PCV has caused the gasket on the bottom of the plenum to suck into intake, allowing the oil to be sucked into the combustion chamber(oil loss) and built up in your combustion chamber and foul everything thereafter(including the catalytic converter) and causes the pinging.

 

Mantis, is there an easy way to KNOW if cat is fouled also? which gasket kit do you suggest for plenum fix?

 

If you pull the front o2 sensor and it runs better you'll know the cat's clogged. Replace it after you have fixed the Plenum. What you want is a Plenum pan made out of 1/4" thick aluminum. Best deal I found was on eBay. Then you'll need new intake bolts and an intake gasket set. I used felpro. Really consider doing cap/rotor and wires if it's due. Much easier with intake out of the way. Also timing chain and water pump. It's not much more work after the manifold is off. Truck will run way better!

 

The cat is clogged, do not start the motor after plenum repair without replacing it and the o2's.

 

What Zman said. If you're going through a noticeable amount of oil, that partially burned oil has already lined the honeycomb of the CC and baked on. It is toast. I simply took the cat off and beat out the CC material and it works fine. Others have said doing that has caused them to get repeated error codes. But for me, it hasn't done anything but make my stock exhaust sound REALLY COOL!