Hey I just bought a 93 del sol s. It is an awesome car, just has a high idle speed and runs a little rich. it came with a p07 ecu, the wrong one for the d15b7 engine. so i bought a p06 ecu for it. I put it in, and the idle speed went up.
at first it idled around 1500. ive already disconected the IAC and turned the screw all the way down, and now its @1000.
i thought the right ecu would fix the running rich problem, but i still have black carbon deposits coming out of the exhaust.
it does have dc headers, short ram intake, and a full exhaust on it. would those upgrades have an effect on the idle speed?
does anyone know how I can fix this? should I buy an adjustable FPR? new throttle body, or maybe its my IAC? or should i just put the vtech ecu back on there?
oh and it also does this wierd thing, if i press the gas pedal real quick, the rpms just drop to 300-500. as if its getting too much air...or gas. can also smell the gas when i do this.
any suggestions? thanks.

 

have you checked the timing ? any vac leaks? CEL on?

 

i havent checked the timing, good idea. there are no vac leaks though. and my CEL is not on, but i think theres something wrong with my cel, or the ecu wiring, becuase when i bridged the diagnosis with a paper clip, turned my ignition to 'on' the CEL still didnt come on.

 

cute car, rims are scary though.

have you checked your plugs?
is there a screw on the throttle body you can adjust?
also check to be sure the throttle cable isn't too tight, just manually push it and make sure it isn't too taut

 

my spark plugs are pretty bad, signs of detonation. black carbon deposits. i have new ones, just didnt put them on yet because i wanna fix the rich gas problem.
yeah, there is a screw on my throttle body, ive messed with it, and it didnt do much, but i think ill just take it off, and see what that does.
ive adjusted my throttle cable, its good.


ha, just realized my rims look bad in that pic. ill put a new one.

 

same thing with my car.
I'm pretty sure its my timing.