FastDemise

Update Time I have grabbed a bunch of spare sensors from the junkyard, Replaced the alternator as I noticed my voltage was fluctuating and now I get a solid voltage output. I've gone as far as unhooking the vacuum hose from the rear PCV and listened as the rpm's rose then returned back to exactly like the photo shows in my first post. I reconnected to hose and then tried the Uncle Bob approach. This also yielded no result as the truck just readjusts the idle to stay low. Seems my IAC is working beautifully based on how it responds to vacuum leaks and forcing the throttle stop open. Now the question is what sensor is giving the ECU bad info that is causing it to maintain my low idle. I have a knock sensor unhooked and have been driving it last few days without connected. That is where I am at now. Will keep reading up on others online that have had low idle and all the different fixes people have come up with.

So I was able to get a good deal on a 97 D30. I get the stronger Ujoints, good unit bearings, and best of all gears that match the D44. Thanks for the advice and help.

I'll take your response to mean replace not rebuild.

Recently purchased this Comanche and got around to the diff fluid. Found the front was just muddy water. I can't rotate the pinion gear without great force and a hammer. Like a lot of sand and junk in bearings or it grenaded. The main carrier bearings rotate freely and easily. Both axles are of the 3.73 gear variety from a Cherokee. I also have the D44 that I got welded to fit truck. If I grab a newer axle I can upgrade to bigger joints and get rid of the vac-disco. But I believe only early models had the 3.73 gearing. What kind of options do I have? Comanche are very uncommon around here in the Oregon and I have never seen them in local yards. Can I just repair the bad bearing and be good? Here is a photo of the wear on the teeth due to bad pinion bearing.

I already tested the fuel regulator a few weeks back and it was 30 with vacuum connected and 40 when it was disconnected. I will grab a can and start looking for a vacuum leak. I replaced the manifold gasket and trucks is running better but now it's rock solid at around 200-250rpms. Starts and runs great. Just idles real low and you can hear the idle slowly waver higher and lower rhythmically. It runs dependable now I just gotta start on my wiring upgrades and find any pesky vacuum leaks. Thanks for all y'all help so far.

So I'm on hold until I can get a new manifold gasket. Seems checking manifold for tight bolts revealed all lower bolts were loose enough to move with fingers and rear most bolt in exhaust was just gone. So took everything off to clean up carbon buildup (last tank I ran only 12mpg) then I can replace the old gasket. Got a new coolant sensor, o2 sensor, and replace quick disconnect fuel orings in fuel rail. Will see how long it takes to piece back together in my free time and if my low idle problems ago away.

Oh yes, I already have your list printed out and following up on all my grounds as we speak. I followed #8 & #14 when I adjusted the throttle body. I'll check the resistance of my MAP and temp sensors then follow-up with the O2 sensor. Will update with results.

I can pull a vacuum line and listen to the rpms rise to 1k then adjusts itself to a nice 500rpms automatically. But if I replug the vacuum line to quick the engine will stall. I have to slowly reconnect to let the computer catch up. It seems the IAC works but much slower then my XJ which responds very quickly and has no trouble adjusting. Jeep Driver, good luck on completing ur build. It's really impressive.

Cleaned throttle body in ultra sonic cleaner so it's spotless. Went thru and adjusted the TPS spot on. Sensor tested good with smooth transition in voltage from closed to WOT. The P.O. was adjusting the butterfly valve as 'idle control'. I have the butterfly stop set so it just touches when it closes and no visible light passes thru. What can I look at next? http://i.imgur.com/YB5dg6c.jpg