My car is a ek9 96 with a b18c1 GSR USDM engine
Yo this car is getting annoying...
I had the thing running perfect and now i think my iacv is causing a problem.
When i start the car up in the morning i let it run for a few... and then i drive it. It runs perfect for a bout 5-10 minutes, i mean vtec screams.. torque feels fine butterflies correctly open up.
After about a couple lights or between 5-10 minutes the car starts to lag incredibly.
Even if i drive normally u can feel an incredibly total loss of bottom end power.
I feel like its going no where even if i would let the vtec hit.
If i pull over and leave it sit and cool down for a hour or so i can drive normally for another 10 mins before the same problem arises. heres the issue
I ran a diag unit on the car and got the p1508 code, a misfire code, and secondary o2 sensor code.
Now i have replaced the iacv twice. I replaced the eacv twice.I rechecked the car wiring too cause i am using a hx harness on the p72 obd2. and i checked all spark plugs, wires, distributor and timing.
I cant find the problem and no longer know where to look.. What do you guys think could be wrong. Please no flaming... ive done enough with the car...

 

check the spec of the coil, ohm out the plug wires. did you plug in or got the 2nd o2?

 

Yes i did... i had a second bung made for the secondary o2 but couldnt locate the wires to use it so i plugged it for now. I just tried my p28 ecu obd1 with the car and it ran fine just i want to use my obd2 ecu for the butterflies. I jus realized when i am revving the car at 1500-2000 rpms it bounces up and down a lil bit.
Im gonna recheck my distrib wiring tomorrow...... I dunno wut to do

 

the IACV isn't going to make the performace of your car change (besides idle obviously).

i had a similar problem with my b16 in my old hatch. it turns out the motor was underfueled b/c my fuel pump was dying. when your motor is cold, the ECU dumps more fuel to help warm up the car. when you car switches to closed loop mode when warm, the fuel is trimmed.