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.

 

are there any check engine lights?

 

Check the IAC for the idle, and the O2 sensor for the running rich problem, that's where I would start, O2 sensor may be shot, and prob keep the stock ecu with the B7...

 

no, the engine check light isnt coming on. then again, i think there is a problem with my ecu wiring, because i bridged the diagnosis connector with a paper clip, turned my ignition to 'on' and the light still didnt come on.

 

ive already cleaned out the IAC valve. alright, ill try replacing the O2 sensor. and yeah, i put the stock ecu back on, thats the P06 for the b7.

 

I am still having a few problems with my idle speed! ive tried adjusting it, and now i think its running lean, on idle. im almost sure there are no leaks, ive cleaned the IAC, checked my intake, for leaks, adjsuted the screw on the throttle body, and the air screw. its idling a little higher now, and seems to have lost a little power. anyways, any other sugestions?

 

Did you replace the o2 sensor yet?

My friends b16 is doing the same thing, No check engine light, high idle after warmed up, smell of fuel, carbon comming out of the exhaust, ( if i put my hand on the exhaust tip my hand will be spray pained black)

the first code i got a while ago was a Oxygen Content code, the car DID have an adjustable FPR, but for a stock engine it wasnt needed

Id really try the o2 sensor, im getting my friend to do the same

 

sometimes cleaning the iac isnt enough and a new one might be needed, check and clean the throttle body also becuase carbon can and will get caught in it and cause it to stick open a bit

 

alright, ill try that too. thanks