89whitetoyota

I am about to pull my manhood off at this point. Can the MAF cause the motor to be reving up this high, looked at all the hoses and they are fine, i sounds like the flap in the maf is slamming randomly.

How do i test to make sure this is OK.

Junkers88

Leave the manhood intact! You'll need it to pee on the tires when you get this figured out. And you can wave it at the truck and say "nayh, nayh, nyah" like an evil character in a black and white movie. Be sure and twirl the mustache while you do.

Did you buy a new IACV? If so then you probably need to meter the MAF and TPS and be SURE there is no air in the coolant system.

PETDOC

I'd check and make sure your throttle valve is not getting stuck partially open. With the truck at 2700 rpms open the hood and close the circular piece where the throttle cable attaches. If the rpms go and stay down clean your throttle body, check your Dashpot and check your throttle cable.

89whitetoyota

I bought a new TPS 2 weeks ago and did it according to the 4crawler write up, is it possible that for some odd reason its wrong and could be telling the ECU that it is WOT?

Changed the TPS 2 weeks ago and over the last 3 days I get this ungodly high idle that makes no sense.

SO far I have 200 dollars in brand new parts. This thing at cold fires up to like 3k or 3.2k then will drop to like 2700k

I am about to load the springfield tactical xd 357 sig, and start swiss cheesing it.

89whitetoyota

New IAC and new TPS, I will run the numbers on the TPS tomorrow, and let you know.

DupermanDave

Did you test the airflow sensor yet as per 4crawlers instructions?

89whitetoyota

I did the TPS according to 4crawler, but I didnt know he had of for the Airflow, do you have the link.

DupermanDave

yup:

http://www.4crawler.com/4x4/CheapTricks/AFM/index.shtml

RustBucket

iTrader: (1)

Have you verified that your throttle plate is closing all the way? Is your throttle stop screw still there?

DupermanDave

Yes, double check this. My butterfly valve was not closing on my 22re and I ended up needing a replacement throttle body on mine. Fixed my idle issue. I have a video of what mine was doing.

Flash319

You can't have a high idle without air. Air comes from 2 places normally. The IACV under the TB or past the butterfly. If you know for sure that your IACV is working then you must have a vacuum leak further in (brake booster? leaking gasket......). The TPS alone can not force a high idle. The ECU has no control over air intake on a 22re.

89whitetoyota

i adjusted the other throttle STOP screw and now I have managed to get it in the 1500rpm range which I can deal with for the time being.

the butterfly had clearence before, nothing big but enough to let more air by than needed.

Flash319

I have always set my butterfly to close all the way, then adjust the idle screw to the desired rpm (700-800 warm). If you can't do this then you have a leak. If your idle does not go down to that range when warm the idle will start bouncing.
You have to find out where the leak is. Dead cold motor (-25C), IACV wide open you can see 2200rpm but it should drop within 2 min as the coolent warms up and closes the IACV.

You can try plugging the port in the TB that goes into the IACV and see if that is your problem but I don't know what you would use to do that, playdough maybe????

Hadmatt54

Toyota TCCS describes ISC operation in the following manner.

“The ECU is programmed with target engine speed values to respond
to different engine conditions. (coolant temperature, air conditioner on/off, etc.). Sensors transmit signals to the ECU, which, by means of the ISC valve, controls the flow of air through the throttle valve bypass and adjusts idle speed to the target value.”

So the ECU controls engine idle and if you don’t have any vacuum leaks that may affect the idle, the ECU controls the idle from the information that it gets from the sensors. Air conditioning on or off would only change the idle a few hundred RPM, but with this being winter and low ambient temperatures outside it takes longer for the coolant to get up to operating temperature and if the ECU in your truck doesn’t think that your engine is warmed up, it’s never going to idle down so I would check and see if the engine coolant temperature sensor is operating properly. Don’t confuse it with the water temperature sender for the gauge or the water temperature switch for an idiot light, the engine coolant temperature sensor is purely to provide engine temperature status to the ECU on terminal THW.

I’ve got a similar problem on my 86 with a 5M-GE, my idle has been high and it would not idle down, but last week we had few days where it warmed up above freezing and the idle was where it should be. Today at 14 degrees
the idle is back up. Mine is probably the original and it’s resistance values at different temperatures are probably not what they should be.

The 86 FSM has a full page of troubleshooting steps for a high idle speed, with the last recourse being changing the computer. Your truck is a 92 so if you don’t have a FSM there is a link on this site for the 95, the steps may be closer to your year.

Hope this gives you some ideas before you turn yourself into a eunuch!!!

Flash319

There is no ISC valve on a 22re. There is only one other air bypass that I forgot and that is the air conditioning idle up valve (if you have it). It is on the intake and has a spring with a screw for adjustment. All it does is open up and cause a vacuum leak which raises the idle.

mcktom

Is the truck idling eratically..Idle high then drop down..If it is then you have air in youre cooloing system when the air passes youre temperature control sensor it causes the engine to idle high then when coolant passes the engine will idle down..Happened to me.Air could get in after a system flush..Someone told me head gasket also....

NOBR8KSS

I "deleted" the IACV on my 22RE a few months ago and it cured all of my crazy idle issues. I was originally going to replace it, but after seeing that they were $150, I decided that it wasn't worth the cost to me.
If you've ever looked at the IACV, it's just a spring loaded plunger with a rubber tip...it's archaic at best and it doesn't work right anyway, so I decided to ditch it.

Here's what I did: I removed the IACV, filled that idle air port in the throttle body with epoxy, let it dry, sanded down the rough spots with a Dremel, and then reassembled everything. I adjusted the hot idle to 850 rpm using the idle air screw and now it stays at 850 rpm whether the engine is hot or cold. On very cold mornings, I rev the engine to about about 1200 rpms for maybe 30 seconds, and then it idles at 850 rpm on it's own.
Idle will still bump to 1100 when the AC is on. No more surging, no more 2000 rpm idling issues.

A little bit daft, but it worked and it only cost me some epoxy and some time.

89whitetoyota

Ok i didnt think about the A/C valve, that could be it. Funny thing is I got it to idle perfect last night and then this morning, it went right back to 2700 on my way to work this morning.

I noticed that throttle body gasket was half gone yesterday when I was dicking with it, so i used some silicone to see if that would help, and it seemed to fix it for a little bit, but its back. I think I need a new gasket there and check the A/C or brake booster.

I have a NEW IACV, so that shouldnt be the issue its gotta be coming from behind the throttle body some where.

NOBR8KSS

Well, even with a new IAC vavle, when the engine is cold, the valve is open. It will let a lot of air in when it's open.
You definitely need a new TB gasket first, though. Fix the obvious problems first and then try to track down the little gremlins.

89whitetoyota

This thing idles at 2700 when warmed up, with NO surging, NO bouncing, just goes right up to a smooth 2700.