S2000 started smoking today like crazy out of no where and then stopped. I let the car sit and idle for around 5 minutes or so and then when I went to back it out of the driveway it smoked like a 2 stroke on a cold start. White smoke. Once i drove down the block and turned onto the main road it stopped. The car was already warm before idling. So I got home and pulled the plugs on it and heres what i got. number of fingers in pic represents cylinder number. 4 was looking darker than all the others. Did a compression test less than a month ago and got 225-235 across the board. The car wasn't missing or anything. I did notice whenever i pulled the hose off the PCV valve there a decent amount of oil on the tip of the valve and hose. Car wasn't being ran hard or anything, just normal cruising under 5k. Oil was a clean golden color. Also didn't notice it running odd or out of normal. Did just replace the intake manifold, installed kpro along with new oil jets and valve retainers in the last 500 or so miles. Any ideas?

 

You might have just had lots of condensation in the exhaust system, it will cause a whitish exhaust vapour. Spark plugs look normal, number four does tend to run differently , it may be burning a bit more oil or running richer than other cylinders.

When you changed the intake manifold did you use a new intake manifold gasket ? , hopefully not running one of those thermal plastic gaskets ? Maybe check the torque on the intake manifold nuts to make sure it is tightened down. Probably fine but worth a check.

 

All the plugs look normal except #4 which looks irregular in that it looks like its sooty, like its not firing consistently, or poor working fuel injector. Not really seeing anything related to white smoke/coolant on it though, or oil contamination on plugs for that matter so at a bit of a loss there. Not sure the #4 cylinder is correlating to your white smoke issue or just hasn't had time to reflect that yet, but it would seem as though a possible coolant leak into that cylinder maybe slipping past gasket on intake manifold you removed. Are you running a Hondata style thermo gasket by chance? Manifold bolts and nuts are all tight? No signs of coolant leaks anywhere?

 

No signs of coolant leaks anywhere and used a brand new honda gasket when i replaced the manifold. All the bolts I checked that I can get to are torqued down fine(24ish ft-lbs). One main one i couldn't get to was the on the bottom of cylinder #4. Wondering if that bolt has worked itself loose. If it were leaking coolant from the gasket wouldn't it do it all the time? I let the car idle for a couple minutes and revved it some whenever I got home and there were no signs of smoke or the problem. Also the exhaust smelt strongly of burnt oil whenever it was smoking could've been a coolant smell but i have never really smelt burning coolant.(rolled my windows down while stopped when i noticed the smoke as i backed out).

 

^ coolant smell has a very pungent sweet smell to it , different than burnt oil. The one manifold bolt on the very corner near cylinder four is important as the water jacket hole is there where coolant runs through the system, a leak there will end up in the intake manifold. But that torque is only 16 foot lbs, if you torqued them to 24 ish it is likely fine ?

 

I read to torque them from 20-25 on the Hondata manifold write up so I just did that when I put them on. Maybe they say more just because of the shitty Hondata gaskets. As long as they didn't break I guess it's fine? Lol

 

yes that torque is fine.

 

Leak down test results. Pretty damn strong in my opinion. 78k on the engine

 

Numbers look good. I've also seen smoke on mine after extended idling [especially when my oil is filled near the H-mark on the dipstick.]

Did you smell yours? Did it smell like something burning, or the sweet coolant described above?

What part of the country are you in (weather-wise), you sure it wasn't water vapor?

 

I'm in Kansas City so it is cold but it definitely smelt like oil. I tried to get it to do it again and I can't now. Drove it around a little and then let it idle for 10 minutes and revved it and nothing. Wondering if maybe the pcv could've got a little gulp of oil for some reason? Really at a loss at what it could be besides possible my intake manifold having a loose bolt which I am going to check tomorrow. The one that would be causing 4 to leak I can't really get a good turn on without taking off a coolant hose