Gmaster

Hey guys, just got my project 88' mj running. shes idling around 2k so I noticed if I plug that hole in the top (not the iac hole) in the throttle body she idles normal, whats it for? Is it supposed to be open? Thanks for any info. 88mj 91ho motor converted to renix. Egr delete, pacesetter header ba10/5 4x4

cruiser54

Both of those are supposed to be open.

They provide the air for base idle and the air that the IAC controls.

Which intake manifold gasket did you use on the swap? Renix or HO?
You may have a vacuum leak at the intake manifold to head.

Gmaster

I used a renix gasket from carquest. I figured its supposed to be open but its just strange it seems to idle fine with it plugged, ill have to check for vacuum leaks whenever I get the time to mess with it again.

cruiser54

It's pulling air from somewhere else.

Bobolink

When you deleted the EGR, did you leave the valve in place and close it off somehow. or remove the valve and fabricate a blockoff plate? Just asking if that could be a source of your leak.

cruiser54

Excellent point.

Gmaster

Update!!! It was the throttle plate hanging open from the po udjusting the stop screw, i adjusted It to were it just rests on the screw. Now shes idling spot on, but surges down sometimes, like its going to stall but then it jumps back up to about 600rpm, what do you guys think this could be? And about the egr delete, I left the unhooked valve in place for now, but found out today its leaking slightly, im going to make a block off plate tomorrow.

cruiser54

Click on the link in my signature and go to Tip 14.

Gmaster

Thats basically what I did, I remembered reading that somewere, but ill check it again. Im also gona adjust the tps and clean the iac. Ill report back with results.

cruiser54

The TPS will definitely need adjustment after resetting the throttle butterfly stop screw.

Do the procedure on the Engine side of the TPS. Tip 8.

lunghd

Excellent 'how to' procedure in your list, Cruiser54.

cruiser54

Glad to have you here!!!

Bobolink

Yeah! Welcome aboard. I've read a lot of your stuff....

lunghd

Thanks - that's what we're here for!

I've had my username registered here for quite a while but never have posted. (Which surprised me - I thought I had posted here before but reckon not). Not much happening over at JU & there seems to be an active userbase here so I'll drop in from time to time.

I was glad to see this thread as I could refer someone here faster than I could explain it myself.

Gmaster

Okay so I adjusted the tps and cleaned the iac and it seems to have worked, idling smooth after it warmed up. Thanks for the help guys.