Replaced IAC, High idle. Please help.

Kaleo
From the P0110 code
You have that IAT sensor
Somewhere.

I’m pretty sure IAT sensor on your taco plugs into the airbox
Let everyone know!

 

@ControlCar

yes sir. I def will tomm.

 

@ControlCar

I checked. I don’t have that sensor anywhere on the box connecting all the way to the throttlebody and down below the air filter. I think I have two sensors in that five pin MAF.

 

Ok here’s what I got guys.
I pulled the MAF and cleaned with MAF cleaner. Let dry for 30 minutes.
Pulled the 20A EFI as was mentioned here. Started right up to reasonable idle, then went back up to 1200 RPM. Drove for 10 minutes. Same. Unplugged the MAF sensor while the engine was running, and the engine died. So the sensor is working.

Before I change five or six vacuum hoses, as mentioned here, and/or pull off the throttle body again, and tighten down the IAC more, I’d like to know what else you guys think I should do.

 

Yes, I confirmed my 04 has that sensor built into it.
“”5-wire connector to MAF on 98-04 have IATsensor built in. 3-wire MAF on 95-97 haveseparate IAT sensor.””

 

I think you may have misunderstood what I said:

That gasket can be tricky to seat correctly, and it can pop out of it's grooves. When you tighten the IAC to the throttle body, you need to be careful that the gasket is not getting pinched into another cell in the IAC. I have used a small pick tool in the past to get things lined up nicely as things are going together.

I think aside from cleaning the MAF, you need to investigate the potential vacuum issues.

 

Yes, sir, I actually had what you said in my mind as I was tightening it down. Thank you.
Just trying to do other things before I take everything apart again to reseat the gasket.
Replacing five or six vacuum hose lines seems the next cheapest alternative.

 

If you are hunting a vac leak you can do a spray test first. Mist spray with water and see if it retards idle or spray with carb cleaner or the like and see if it raises idle. Not liberally but in an effort to find an air leak. One or the other works fine.

 

^^^good trick......it works

 

Do not use brake cleaner

 

Did you use an aftermarket IAC? I did on my 96 2.7l and it would never get below 950rpm. Cleaned old one and put it back on. It worked sometimes even though seemed to pass tests. Replaced with new OEM and it’s all good, steady 700rpm at normal op temp.

My takeaways:
Rock auto aftermarket had diff size valve opening and no thermal spring.Believe that spring further reduces idle as temp rises.

Old OEM IAC maybe had weak solenoid since it was stuck and nonfunctional the 7 years I ran it with a 1100rpm “normal” idle while I was ignorant of the condition. Maybe that cleaning I did got solvent in the solenoid and weakened it. New clocked open and closed with authority.

My advice is use OEM or live with what aftermarket gives you. Same I’ve heard here before and now follow.

Good luck.

 

Guess I’ll go OEM.
Thank you for sharing your wisdom. Can you explain the spray test more detail to me please?

 

I guess I should have asked this first. Parts store IAC's are known problems. OEM is the only way to go there.

If you spray water (really a mist) on the hoses or locations you want to check for a vacuum leak, you should be able to hear the rpms change in response if there is a leak.
water/mist = lower
EFI safe cleaner or propane = higher

The vacuum leak will draw in whatever you're spraying at it, and the rpms with shift.

Don't use brake cleaner. Most brake cleaner cans on the shelves now are non-chlorinated, but it's not worth the risk. The chlorinated stuff will kill ya.

 

Thank you guys. You guys rock.
Appreciate the help I have received.

Will advise as to my progress.

 

Well guys, I guess I screwed up.

This is the connection to the IAC. It’s fried. This was the smoke I saw when I started it for the first time. Was this because I didn’t disconnect the negative cable from the battery before I started changing it out? I can assure you I did it now.

Other than going to the dealer and buying an OEM IAC on Wednesday, could somebody please explain to me how can I change this connection? Really need your help guys.

 

I'd try to wire up a new connector. Should be a very simple and cheap fix.

 

So I should cut the wires as close to the old burned connector as possible, then strip them, then connect the new connector, and twist them together?

some black electrical tape after?

 

Buy a new connector (I always go OEM for stuff like this but its your call). Splice wires and reconnect them with the new connector (carefully one at a time to not screw things up). Use wire connectors.

 

Thank you for replying. I appreciate it.
did this happen because I did not disconnect the battery when I connected the new IAC?

 

STANDARD MOTOR PRODUCTS S2823


https://www.rockauto.com/en/catalog...r,idle+air+control+(iac)+valve+connector,2589

shows for the v6… not the 2.7 but i feel like they'd be similar