OK. i bought an 86 22 ret a couple months ago. The guy i bought it from said it wouldnt pass smog so he said he changed one spark plug that looked bad ( ill get to that in a minute) and did the valves and timing. I bought the truck and went to the smog shop and passed smog.

The tech said it was a good looking truck but it had a small miss around 2500 rpm. I noticed an idle miss and a miss around 2500 too.

I then replaced all plugs and wires and the tps and adjusted it according to 4crawl website.

the miss is still present and i am stumped. i know my turbo is cracked on my exhaust housing could that be the culprit? Im gonna have it shpped out to turbo electric to be serviced.

I pulled the spark plugs today and i found that #4 plug looks like Sh**. I cant understand it. it doesnt smell like gas and it was a little oily so i checked compression on the #4 cylinder again and its @ 150.

Could it be my injector? Cap and rotor? I double checked my tps and its within spec on all 4 tests. IM STUMPED AND NEED HELP

The pic with 2 plugs is #2 and 3. The other clean plug is #1 and the nasty one is #4. plugs are two months old

 

I verified last night the timing is at about 5 to 6 btdc with plug jumped. I havent looked at the valves yet. OH and the truck has 182,000

 

Youre burning oil it seams. I'm guessing its the valve stem seals since compression is decent. What is the compression from the others?

 

compression is around 145 150.

 

Bump. Please help. Pulling the valve cover to check valve clearance and seals. Will it be obvious the the seal is blown when I pull the cover?

 

If its def oil there are only so many options.

What are the chances it's a head gasket or crack?

Is it moded out, or still stock.

Pics help.

 

Its stock. There is no milkyness in the oil and it doesnt smoke

 

Since compression is good,

Must be what vital says. valve seal.

 

My rte was the same, really oily plug in #4 cyl. Sounds like valve seals, another thing to check is your egr stuff. Mine was completely choked with carbon. Hope this bit helps!

But also, oil in a cylinder will raise the compression when you check it

 

is it possible to do the seals with the head on? Any special tools required?