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View Full Version : smoke from throttle body? UPDATE



n240sx
02-06-2006, 10:23 PM
I just replaced my headgasket on a brand new (0 miles) built motor (ka24de) since my cometic didn't want to seal. i replaced it with a felpro oem replacement. i got everything back together last weekend, cranked it up and it fired on the first try. at first there was no throttle response at all (where i could floor it and the rpm's wouldn't budge), but that ended up being due to a couple of vacuum ports i forgot to cap. i took the intake off (still running n/a til i get all my turbo parts), opened the throttle body, and white smoke came out of it very slowly. i'm not exactly sure what this means, but the only thing i can think off is maybe i don't have my 248 intake cam rotated incorrectly by one link. this could force the combustion from the exhaust stroke back through the intake valve if it closed too late, couldn't it? as of now, it runs/sounds fine as long as i keep my foot on the gas. i did spray a rag with brake cleaner and wiped down my throttle body before i cranked it up, but i doubt that has anything to do with it. any help would be appreciated. thanks

wizdom240
02-07-2006, 10:31 AM
It's most likely your cams. Is the intake manifold warm/hot while idling? If so, you might have the cams on the wrong side or timed wrong.

n240sx
02-07-2006, 01:34 PM
the car won't idle, which is the main problem. i have to keep my foot on the gas to keep it running, and when i do that it revs, and runs nicely. releasing the throttle kills the engine almost instantly. the intake manifold is warm, but nothing compared to the heat coming off of the valve cover and exhaust manifold, which leads me to think that everything is fine minus my idle issue. btw, the cams can't be on the wrong side because they are both the same cam (dual exhaust cams). the 248 exhaust cam is rotated to work on the intake side. i will check this weekend on whether or not i screwed up on the timing, but i'm pretty sure that i did it correctly, which is leaving me pretty stumped.

cdlong
02-07-2006, 03:50 PM
are you sure it's smoke? there is coolant that runs through the TB, it might be leaking or something. probably not, but it's a thought.

tErbobOOst
02-07-2006, 04:49 PM
How bout the fact that it is a newly rebuilt motor and it may be oil/grease that is slowly burning off.

I bet your idle problem is unrelated unless its A LOT of smoke. Are you sure your IACV is working properly?

TS4l
02-08-2006, 11:14 AM
I was thinking the same about it being a new engine. After doing a lot of work on an engine it almost always burns off some oil and even grease from your hands. How long did you run it?

n240sx
02-08-2006, 07:18 PM
are you sure it's smoke? there is coolant that runs through the TB, it might be leaking or something. probably not, but it's a thought.



i don't know what else it could be cause i'm pretty sure that there aren't any coolant lines that run inside the throttle body/intake manifold. although i could be wrong.



How bout the fact that it is a newly rebuilt motor and it may be oil/grease that is slowly burning off.

I bet your idle problem is unrelated unless its A LOT of smoke. Are you sure your IACV is working properly?




it's not a lot of smoke, but I thought it was enough to make me a little concerned. i just assumed the IACV was working. i think i forgot to mention the fact that it DID idle once and fluctuated between 200-400 rpm until i tried to adjust the idle using the screw on teh iacv. it died right after that (possibly turned it the wrong way), and wouldn't idle after that.



How long did you run it?



We ran it long enough to heat up to normal operating temp.

n240sx
02-12-2006, 09:20 PM
I didn't get to spend as much time with the car as i wanted this weekend, but when i tried cranking it, it would not fire. I pulled the plugs and they had a good bit of oil on them. is this to be expected since the motor has yet to be broken in? after i replaced the plugs, it fired right up and idled pretty good (changed nothing since last time ) , but low. so i tried to adjust the idle again and it bogged whether i turned the screw left or right. also, if i would give it a quick rev to about 2 k, it would die immediately after the rpms dropped. i tried looking/hearing for a vacuum leak but it's kind of hard to hear anything with a open header ka (i also lacked throttle body cleaner). if my boost gauge would have come in like it should have, i would have been able to confirm it. now to wait until next weekend . . .