Race Egr

I just swapped a ls motor into my eg hatch it starts up and runs good when accelrating and it will idle at 750 for about a minute, but then it will drop down fast and almost stall out and when i step on the gas it wants to stall even more what could cause this. Also, i checked the plugs and they have alot of carbon on them and it's not throwing any cel's. All help is greatly appreciated

Red_EM1

is the o2 sensor ok?

Race Egr

seems good to me its not throwing a cel light ,but i didnt have the exhaust hooked up just straight header

NA95d16z6

if the plugs are dirty then replace them
NGK PLATs =

is the compression good?

Race Egr

compression was good, the plugs where new could timing do this?

NA95d16z6

wait.... you said the plugs had a lot of carbon on them????

timing could be an issue, if its severely retarded. if you gotta timing light hook that bitch up and check her out. but you would probably be able to hear if the timing was off (if you know what it sounds like)

Race Egr

yeah the plugs had alot of carbon on them after just a short period of running. It will idle fine for about a minute then it will drop really low like its gonna stall then shoot up to about 1300 then start all over again. My only guess would be the timing

Race Egr

bump for some ideas

NA95d16z6

sorry i woulda posted sooner but my computer tried to off itself.

does it keep doing that over and over again. up down up down etc. etc.?