Smoking after VTEC?

First off I have searched but couldn’t find anything this specific! Well I just recently swapped a 94 B18c1 w/64,xxx on it into my 91 Ls. Setup is as follows: 94 B18c1, PR3 ECU, Comptech header, skunk 2 IM, resonated test pipe. OK the problem is after I hit VTEC when I come to a stop there is a good amount of smoke coming from my exhaust briefly, then it goes away. I had a friend follow me today and he said when I get on it 4800+ rpm it smokes a bit but if I drive normally nothing at all. He said that the smoke looked like it was white at first then he said it seemed blue?

I haven’t yet performed a compression test. I plan to do that on Sunday. But from what I have read it could be a blown Headgasket? But my thought is it would do it all the time. I also read it could be rings, which smoke during acceleration, or valve seals which smoke during engine braking or deaccleration. I also read that a plugged PCV valve can cause you to burn oil. Any ideas or suggestions would be appreciated.


since you’re too good to be on AIM, do your compression test joshypoo and we can go from there. :up:

Don’t rule out a head gasket, the high cylinder presures at high rpms could be causing a small leak in the head gasket, that are only apparent at those times. Good luck.

but if its also blue thats usually oil …but yea do a compression test or take it to a reliable machanic if you really cant figure it out …

Thanks guys, I am taking it to Honda on Monday, I have a friend there and he is going to hook me up with one of there better techs to get me pointed in the right direction. Just for shits I replaced the PCV valve today and it seemed to have reduced the amount of smoke. The old one only rattled half the time at most so that was shot. I am hoping its only a head gasket, otherwise the LS engine is going back in and I am going to build the B18c1 to get a bit more perfromance. I was thinking of maybe some ITR pistons and cams. Basically an OEM rebuild with the better OEM parts…:wink: Suggestions would be appreciated…



i hate when stuff breaks but i love the outcome …its just a reason for me to go bigger and badder :crazy:

Wasn’t able to get the compression test done today, hopefully tomorrow. But I will keep you guys updated on what I find.


It sounds like HG to me too, it just can cause so many symptoms…

Ok I am almost positive its a HG. I did a compression test today and with the throttle closed I got:
cyl 1:160
cyl 2:125
cyl 3:130
cyl 4:160
I read somewhere that if the lower cylinders are right next to each other its most usually is a headgasket. My other question what cylinder pressure should I expect to get on a stock p72 in good shape? Thanks for all your help guys…


you did a closed-throttle test right? normally you want to have the throttle plate open. :wink:

those numbers seem a bit low, but i would say do one with the plate open and let us know what you get. :up:

(helms spec for a stock GSR brand new is 270–typically people with used engines tend to be around 180-220)

I tried one with the plate open but it was going pretty high and I couldn’t tell how high, so I stopped thinking that that wasn’t right. LOL Oh well I will do it tomorrow.


eh, just watch it; if it’s over 200 after 5 or so cranks then you’re fine. :up:

Ok this is what I came up with.
Cyl 1: 227
Cyl 2: 185
Cyl 3: 182
Cyl 4: 230
Much better looking than the previous numbers.


there it is!! i had a feeling that was the problem.

granted, your headgasket’s gotta come off. but those other two cylinders look just fine.

Yea its the HG most likely, BUT I’d try dropping a teaspoon of oil in the chamber then do the test again (just for the low cylinders). If the compression rises significantly, then it’s your rings. If it doesn’t rise much (like less then 10-15) then its the HG. Cause that would suck if you did the HG and it turns out to be the rings…

headgasket fer shizzle. :sad: could’ve been worse!



where the fuck are you stationed now big boy?

love, your offutt/keesler/lackland punkin (mark). :stuck_out_tongue:

LMAO remember what happened last time we jacked a thread? make a new one. lol. or use global address book and look me up.
Charleston AFB, SC btw :wink: punkin??? lol

Just an update here guys. Well I recetnly started a new job at Honda. And the tech that I am paired up with decided we should do a leakdown test. Well what we found made me very unhappy. Cylinder 3 was infact a headgasket problem, but cylinder 2 thats another story. We belive I have a ring or a valve issue. So I have orderd all the parts I will need to get the job done. I am going to rering the pistons, and a complete valve job. So hopefully I will be back on the road NFULFX in no time…LOL just kidding Neil. This is a valuble I have learned…Don’t go through the trouble of swapping in an engine you only THINK is healthy.

-Josh :cross:


I coulda toldja that, gopherboy. :stuck_out_tongue: