Ok, so i have a turbo ek converted to obd1, running a b20 block with b16 head and b16 tranny. Low boost, only 10 psi on small turbo. Car has full fuel system upgraded and RC injectors are more than enough, fuel pressure is perfect at idle and cruising.

Just recently car had IACV plug come loose and threw code 14, so i checked it out and saw plug had fallen off, plugged it in and CEL went away and it idled fine now. Car now shudders when you floor the gas pedal. If you slowly build boost and ease into throttle it drives fine, but when you floor it whether you're at 2k rpm's or 6k rpm's it will shake vigorously almost as if i was hitting a rev limiter or something and you can smell car fun rich for that brief moment. It will shake until i let off throttle and get back into it.

No codes are being thrown, all cylinders are firing, and again, fuel pressure is good. Idle is sitting perfect. I thought maybe ecu got messed up somehow due to iacv code eing thrown so i unplugged battery and connected terminals and unplugged ecu for awhile, but still doing it.

Thinking about just getting chip reflashed and seeing if it helps, because i'm all out of ideas. Honestly feels like spark and fuel just get cut off out of nowhere, and it's only under load. No matter what RPM it doesn't like having wide open throttle.

If in neutral you can go WOT and it is fine, but when motor is under a load it just suffers. Open to any ideas since i'm stumped

 

I have also been thinking it can be MAP sensor related, i have already taken tbody off and cleaned all the sensors (they weren't bad), might try to just replace everything if tune doesn't work... but i know if i replace tbody, sensors, dizzy, wires, plugs, etc that i'll turn this car into more than a daily driver and im trying to avoid that! lol

 

What is this tuned on?

 

Its got an SST chip tuned on crome, never had this issue

 

Well now you do. Basemaps go bad you know. Are you not running any gauges? What is your AFR looking like when this happens? No other CELs being thrown?

 

Sounds ignition related to me. Check plugs, wires, cap, rotor, etc. Try replacing with known good parts if you have any laying around.

 

True. I've never seen an IACV issue cause these symptoms.