Hello,
I'm having a hard time getting my fresh b20v build to idle. It has 12:1 compression pistons, blox type b cams. No vacuum leaks, mechanical and distributor timing both correct, tps calibrated, no check engine lights for fuel injector or iacv. Run stock map on an OBD1 ECU with stock injectors. Does not have knock sensor, was hoping to disable it when i tune.

Idle is slightly stable at above 1000 rpm ~ bounces 50-100 rpm
Below 1000 rpm the idle bounces 700-1000 rpm. I sprayed alot of break clean and dont think its a vacuum leak.

Been playing with the screw that holds throttle body and idle adjust screw on the throttle body haven't had any luck. Am I missing something? Do I need to burn a chip and make adjustments through ecu? Or should i be able to get car running stable as is with the stock ecu before taking it to a tuner? Thanks in advance.

 

Valves adjusted correctly?

 

I'm pretty sure the valves are adjust correctly. I'll double check them when the car cools down. They sound good though. I don't understand why the rpms are bouncing.

 

Update with this?

 

You need a tune. A stock map does not do well w/ bigger cams. Vacuum values w/ stock cams vs big cams is totally different. It's trying to compensate with fuel (most likely) which will make it go rich/lean and cause a jumping idle.

 

Ya I would totally agree, practically built engine trying to get to idle on 12.1cr with wrong in.s and on stock ecu map, I would say be happy u can rev it to dunk.

 

Got the tips and map hooked up to the right connections?

 

have you got a tune yet? i'd recommend a s100 min..prefer a s300...that way u can tune on the fly depending on weather