×

Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

7MGTE, ECUMaster EMU black, issues with IACV

General Tuning Discussion

Forum Posts

Courses

Blog

Tech Articles

Discuss all things tuning in this section. News, products, problems and results. 

= Resolved threads

Author
154 Views

Hi everyone, First post here. I have a 1987 Supra with a 7MGTE.

Recently installed an EMU Black and made my own wiring harness for it using ECUMasters Flying lead kit. I'm also using a base map from ECUMaster for the 7mgte.

The car is running and idling but I'm having trouble with the IACV. I'm still on the stock Toyota IACV wired to be unipolar as in this diagram from ECUMaster.

It doesn't seem to be working correctly, I have it vented to atmosphere right now as the stock setup that routed it back to the intake is gone. Currently the car is idling too high, around 1100-1400RPMs. When I try to adjust the idle target down the RPMs will go from around 1100 to 1200. When I adjust the Idle up to say 2000RPMs it drops to 700ish. I unchecked "Reverse" in the idle parameters and it didn't really have any affect.

I checked my wiring to my ECU pins with a multimeter today and the wiring is correct. Also when I unplug the IACV while the car is running nothing changes, I would expect RPMs to drop or surge when unplugged, but nothing. Any help is appreciated, Thanks!

Remember you can't reduce the air getting into the engine via the throttle body, or potential leaks with an IACV. You can only add additional air with an IACV, so if the engine runs at 1100-1400 RPM with the IACV unplugged or otherwise disabled and you want a lower idle speed, you first need to reduce the air getting into the engine otherwise.

Typically you want too little air to get into the engine without the IACV, and the IACV adds the additional portion to get you to your desired idle speed.

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?