kuhnski

I have an 86 XJ pioneer with a 2.8l V6, I know it's a dog motor but it was a cheap rig. There are a few issues I am trying to resolve and one of them is dieseling. I have done a bit of research and the most common suggestions are timing, vacuum leak, and idle adjustment. I just want to get some additional input from those that have dealt with this issue. Keep in mind that this car was a one owner rig that was used as a tow vehicle, it has 102,000 miles and almost everything is original.

Here are some of the things I have worked on or are known issues:
-I have replaced about 85% of the vac lines, and some were bad I have since tested and just about all of the lines are holding vacuum
-The electric choke is not currently working, I have it disconnected and set up so that the choke will not come on.
-The air mix solenoid is working but the rubber gasket n it is less than perfect, it needs to be replaced.
-The temp gauge will not go above cold (in the blue) or around 200, from what I read that seems normal, but occasionally it will jump up to around 240-250 and then back to cold. i am sure that this is not related to the dieseling

There are of course a few other issues, mostly internal electrical, that are not likely related. And before you suggest buying parts understand that I am on a tight budget so I would prefer to take a systematic approach.

Any input is appreciated

CPTslackass

Does it have a tach? Can you tell about what rpm range it idles at?

XJ-92

my 4.0L does the same thing. i havent been able to find out the problem yet and it idles at 900 rpms. everything works just fine tho

kuhnski

No tach, that's on the list of things that are needed. It idles rough and seems low and at times like it will die. When I turn on the ac/defrost it gives it the idle boost and that feels stable enough for stop and go driving. If it matters the AC is not working, the compressor pulley seized the day I bought it and I had to cut the belt off.