Im having an issue with light /constant throttle pressure I am getting a bucking /jerking as if someone was tapping on the gas pedal. I am getting a code 14 iacv. This happens even with the car in motion and the car actually jerks around. I was confused as to whether or not I needed to do any wiring like the 3 wire to 2 wire fix because I converted a 97 auto del sol to a b16a3. I used the complete b16a3 swap, engine harness and ecu.

 

Yes, you must convert the 3 wire Del Sol auto IACV to a 2-wire IACV. This should cure the jerking. When the IACV isn't functioning, the engine will buck until the throttle blade is opened sufficiently to not need any supplimental air flow... usually between 2500 and 2800 rpm.

 

So do I just need to move the wires around at the ecu. I wasnt sure because im using an obd2a to obd1 jumper harness so I thought maybe that already fixed the wiring

 

Some jumper harnesses have this built into them... some do not. You guarantee the path way if you move the black/blue wire in the original engine harness (not the jumper harness) so that all works properly. Remember that the ECU "self checks" for sensor resistance at key-on... so if you are getting a code 14 immediately, your problem is either a shorted out IACV or a break in the wiring... no continuity. If however, you clear the codes, start the car up and drive around for a while before the CEL comes on, your wiring may be just fine.

 

Your explanation of the bucking makes good sense but it looks like from the way my jumper harness is wired swapping the wires at the ecu plug would not make a difference. The cel does appear immediately when I start the car. Does this mean it is a bad iacv? I wonder if I should try and run a wire straight from the iacv to the jumper harness? So you know if I can use a dseries iacv on the b16a3?

 

It could be a bad IACV. Since you seem confident that the ground control wire from the ECU is getting to the IACV (continuity on the black/blue wire to pin A9 at the ECU), it could also be that you don't have 12v going to the plug. Or, it is possible that you don't have the correct plug actually plugged into the IACV. It is a Grey plug with the signal wire being either blue/black or blue/yellow and the power wire being yellow/black or black/yellow.

And yes, a Civic IACV will work on your engine assuming that the bolt spacing matches the one you have.

 

So I had to put this on hold for a bit but the problem still going on. I tried completely unplugging the iacv and it still bucks at 1500rpm running the p30 through the jumper harness. I bought an obd2a b16a manual ecu p2t-003 just to try and it sort of works, the bucking actually is gone but it more or less seems like it is running without an iacv since its idleing very low but at least driveable. I would like to try replacing the iacv just to see but the d series iace does not fit and havent been able to locate a b16 iacv

 

Clean the IACV and then adjust the idle speed as per service manual instructions.

 

I did clean it with carb cleaner it made no difference. I still get code 14 at startup with both ecus. There's definitely a iacv issue, either the iacv itself or maybe wiring issue

 

What leads you to this^ conclusion?

Are you running a 2-wire or 3-wire IACV? Without question, the OBD1 ECU will look for and require a 2-wire IACV.

If you are already running a 2-wire IACV, then you may have a massive vacuum or intake air leak.

You may also need to adjust the idle speed.

 

I finally found another iacv to swap in and it did not fix my problem. I want to try to wire it direct to the ecu. I have an extra plug for the iacv so is it correct to wire the blue/yellow to pin a9 on the ecu and the yellow /black just get wired to the positive battery terminal?