Thread: IACV wires fried

So, after getting a p0505 idle air control module error, and not able to get anything working at all for idle (see 'bouncing idle' video) I started testing wires to the ecu. sure enough, BAM! 2 wires are not continuous! the pink one and the green one. So I thought that perhaps in my motor swap, the harness got yanked and the harness was busted. (I had this happen to my tps harness in the past). So I clipped the harness for the iacv valve, and continuity existed on the harness to the wires. Checks out right? no! the pink and green wires when i gave them a light tug, came right out of the sheathing, melted!

PERFECT! So I know know what the issue is in their discontinuity. The question now is this:

I tested both iacv's I have, and both are within spec for resistance on the motor itself as per the fsm. The problem we have however, is if I repair the wires and the motor has too much resistance (perhaps the resistance on it when unplugged is within spec, but when voltage is applied, it doesn't turn, cranking up the resistance, thus melting the wires.

So, the question then, is should I risk fixing the wires, and plugging either 'tested' iacv valves in and hoping for the best (risking melting them again), or should I purchase a new one, spending $125?

Now, let's say I replace said iacv valve, is there a risk that the ecu is fried too because of the resistance being so high I melted the wires?

Did you test the the IACV by using the ground on the wiring harness or did you connect to a chassis ground? Reason I ask is because while reading the G20 FSM for a friend that had p0505 it repeatedly said to NOT use the ground on the harness as it will short out the ECU. No mention of melting the wires but just wanted to share this info as it may be of some use. Now I am not sure if all SR's were the same. Like I said this is from the G20 FSM.

nope, i did it correctly. besides, the two melted wires were not the battery voltage ones.

What you could do is fix the harness and temporarly install some small .25-.5A fuses in line with each wire. So if something is wrong you will blow a fuse and you can try different IACV's or ECU. At least you will know if there is something still wrong.

I tacked it all back together and ran the car for 1 hour - works like a charm! thank goodness!

finally the entire engine swap is completed. If it melts again I will certainly put a fuse in there. Thanks for the help guys

there is a guy on g20.net with a similar problem. Well similar IACV problem. Maybe his wires melted too. Can you take a pic of the wires and where they were?

just have to take off the iacv harness, and measure continuity between the 4 outside pins and pins 6, 7, 15, and 16 as per the fsm downloaded from here.