you guys have any ideas on how i can fix this? Past threads have said to clean or replace the IACV but i find that hard to believe since it was working fine earlier today with my USIM.

Grant

 

Did you start the car with it disconnected?

 

no, actually i think there was a vacuum leak bc we cut a hose that looked to be split some and reattached it. light went off briefly after I reset the ECU but came back on after pulling out of the driveway........ IACV is all plugged up

 

It is a big vacuum leak. Find it, patch it, and you're good to go.

The vacuum leak (big enough) will yeild an idle speed beyond the control of your iacv unit. That's why you're getting the code because the ecu couldn't implement the iacv to dial down that idle speed, thus thinking your iacv is faulty.

I've gone through several variable intake installs, both mevi and 00vi, and whenever there's a iacv code, it's either pcv connection or crankcase breather hose not connected. Hope you find them...

-Peter-

 

I think what it might be is the way we have the vaccuum canister hooked up. I was going off memory when i hooked every thing up vaccuum hose wise for the vaccuum canister and selenoid, and when we started up the car, the MEVI acuator actually closed, so i'm thinking that that might be part of the problem. Also, on the 97-99 intake manifold, there was a nipple just past the throttle-body that wasn't there on the MEVI. What I did was "T" into the other small nipple below the evap port. I used that same vaccuum source for the MEVI vaccuum components. With the vaccuum canister/selenoid hooked up basically backwards, i think there's a chance the check valve in the canister might be the culprit.

I had to hurry off to work after we got everything buttoned up, so i wasn't able to stay and help trouble-shoot the CEL. So grant, if you see this, swap the vaccuum lines on the vaccuum canister, reset the ECU, and give that a shot.

 

yea george we tried that yesterday and it fixed it temporarily but I think Peter is right - theres got to be a leak somewhere but i cant find it

 

problem solved. george switched the hoses on the solenoid and no CELs so far.

 

Have you actually tested your MEVI by setting the dip switches to say, 1500 rpms, pull the throttle cable with your hand, and confirm that the lever on the MEVI actuator moves? Then, after all is good, set the dip switches to 5200ish.

 

i havent done that yet...... and the light came back on......... I actually havent hooked up an rpm switch bc im waiting to install my EU to do that. Ill the vacuum stuff is at least hooked up tho

 

grant, for the time being, take off that second "T" and the short piece of vaccuum tubing inbetween the two, then hook the lower vaccuum line of the second "T" to the other side of the first "T". That'll completely bypass all the MEVI vaccuum stuff and should atleast help isolate the problem (assuming the light doesn't come back on.)