Idle Adjustment Screw 2.6 FI

Mine apparently rattled out. I've got a vacuum plug stuck in it so it will run. Anyone know where to find one? Or anyone have the idle air control unit laying around? I have the ECU unplugged from the IAC bc it idles at 3k with it plugged in. But with this screw gone and the ECU unplugged it idles around 700.

So I guess my second question is the ECU bad causing a high idle or is it the IAC unit.

BTW I hope I posted this in the correct section. Thanks in advanced for any help.

Nobody? I just got done telling a new guy how helpful this site has been when I've had previous problems with the Mini-lade. Damn guys lol.

The first thing you need to do is get that adjustment screw replaced and then set up the base idle speed. I know you're doing the best you can now by plugging it with vacuum cap, but if you start replacing IACs and ECMs without having the base idle speed set correctly, then you are troubleshooting this problems backwards and will probably waist time and money.

I doubt the ECM is bad, although it could be. I'm more inclined to think that it is getting some bad information from a sensor like the coolant temperature sensor. However, if you haven't done so already, I'd pull the computer, remove the top cover and inspect the circuit board to see if there is any signs of leakage around the two large capacitors - they will be about the diameter of a AA battery and about 1/2 inch tall. IF they've already been replaced, they could be smaller. If the circuit board around these capacitors is not just as clean and shiny as the rest of the board, then they have probably leaked and are causing some of your problems. Post some pictures.

Also, when you replaced you coolant temp sensor, you replaced the one with two terminal connecter, right? The single connecter terminal is the one for the gauge. I would check the resistance on the coolant temp sensor and see what you have. I still have the original in my truck but I have seen many other cars with them fail and cause idle issues.

Ok just to clarify the idle issue with the ECU plugged in was present even before I lost the idle screw and before I replaced both the 1 and the 2 wire sensors. (With 2 sensors from the JY though so not brand new but no change from either of them being switched.)

I need a screw still or the thread count/size of the bolt to be able to replace it.

I guess after the screw is replaced I need to replace the 2 wire sensor. Then go from there


So once again does anyone have an idle set screw laying around????

Well I do think you have a problem besides the set screw, but you at least need to get that fixed. I'll see if I can get a spec on one.

Have you looked at the ECM yet? You should really do that since the cost of looking is $0 and it only takes a few minutes. You might not need a temp sensor or IAC valve if it is bad or has corrosion.

EDIT: Also, have you checked the ohms on the IAC?

I haven't checked anything with a meter. I'm going to take a few pics tomorrow. There are 3 plugs unplugged on the pass. side right behind the battery. And the previous owner removed the stock air box, so there's no telling what he screwed up. What about an incoming air temp sensor? Do these trucks have one? bc if so... it's gone. I have the MAF and thats it on the intake.

Looks like I need to go over everything with a fine tooth comb. This previous owner was a dumbass in everything else I've fixed so I should assume his "work" could be affecting this. Again I'll take pics of the plugs in question tomorrow. and anything else that looks fishy. Thanks scotch.

Sure thing. The air temp in on the front one the intake manifold near where the PCV goes in.

Check out that computer. If nothing is obvious, take some pics anyway and post them. Show us the plugs that are unplugged on the passenger side.

Behind the battery is the Main Relay - couldn't be that or you would be running at all.

Vacuum Solenoids - Gas Tank Vent Purge and Fuel Pressure - doubt either would be causing it but here are checks you can do on them for good measure.

AC relay - Wouldn't affect much.

Let us know what you find!

On the driver's side there is a blue 3 wire plug not plugged into anything. Looks like it's located about where the stock airbox was. And on the passenger side there are three plugs in front of the windshield washer fluid tank. If I remember correctly two are yellow and one is green. Up by the fuse panel under the hood there is one white 1 or 2 wire plug not plugged into anything.

Haven't had the chance to inspect the ECU. I'll try to do it tonight after work.

On a completely unrelated to this issue note I found my damn oil leak... it wasn't the distributor like I thought... The damn timing cover is cracked under the dizzy and around to about half way across the front of the motor. I tried JB weld. Needless to say it didn't work. It did slow it down a bit, but there's still a leak.

Well I finally pulled the ECU and this is what I found:



Luckily dad has a friend who can replace them for me... I can solder but our iron burnt out and no solder here lol.