I recently swapped an obd1 b18c into my ek. The only mods have been a clutch and flywheel. When the motor is cold it surges and will die without help until it warms up, when the motor is warm it runs good but it still doesnt hold a steady idle, it doesnt really surge but it may run at say 750rpm for a minute and then rise to like 1100 rpm for a minute. Here are the things ive tried. I cleaned out my FITV valve and i made sure the valve was screwed in all the way. I cleaned out the IACV. Ive changed the o2 sensor. I did a spray check for leaks and found none and all of my hoses are hooked up. Ive also tried another ecu and still had same results. wtf is going on and what else should i try? If u know of anything else this could possibly be please let me know and thanks so much in advance.

 

bump

 

Try your TPS...Got any codes... I used to have a surge in idle...changed my TPS no more surge...

 

take the intake elbow off the throttle body. Start the car and cover the lower hole in the throttle body. Did your idle problem stop if so you have a bad FIT valve, if no SLOWLY cover both holes if the engine dies thats good if it doesn't you have a vacuum leak at the throttle body gasket or at the intake manifold gasket. Or you might have a vacuum leak at the injectors.

 

no codes and i forgot to add that if i try to drive it before it is warm it will sputter, but i will check all that as soon as i get a chance, and if you or anyone else knows of anything else that could possibly be causing this please let me know. thanks for all your help guys

 

oh and im sure that its not the FITV because i swapped it out with one of my friends that i know for sure works

 

chcek your throttle cable. it's probably too short. go to inlinefour.com and order the GSR throttle cable for it.