I recently purchased a 90' Trooper. Was going to use it for parts but everything is there to make a nice driver vehicle. So I have decided to fix it up. It has a couple of problems. One is that the previous owner said that the engine has a bad cylinder. I started it and it does start up easily but it does not keep an idle, has a rough idle and it has white smoke coming out the exhaust. Could this be a head gasket or a cracked head? If so what is the best way to test to see what it is?
Also I am a stickler when it comes to my electronics working. Everything works electronicly except for the Temp & Fuel Gauges. I have already checked the fuses and all of them seem fine except I do not have a fuse in the CLOCK (B) slot and there is a empty relay spot. The empty relay spot is the one that says RELAY P/WINDOWS. Both of these empty fuse/relay slots have wires going to them.Do you know if either of these should have a fuse/relay in them?

White smoke is often a result of overheating, so your own diagnosis is probably right. Pull the sparkplugs for confirmation. Run the engine up to operating temp before pulling the sparkplugs. The bad head will show some moisture on a plug.

thanks. I will check that. Any clue on the gauges?

What engine ya got in yer rig ? Yer symptoms sound like a gasket and/or head problem.

If you don't have the optional clock, or power windows, there won't be a fuse or relay, but the wires are in the harness.

I'll take a look at the schematic and see if I can give ya any ideas on the gauges... I think someone recently asked this, but I don't remember for sure, or what the answer might have been...

Does the OIL PRESSURE gauge appear to be working properly ?

I don't see anything common to both gauges other than the regulator circuit on the gauge assembly, and that also powers the OIL PRESSURE gauge, so if that's working, then the regulator is probably OK. I think you may have two seperate problems with the guages, either wiring, or the temp sensor is bad, or the fuel gauge sending unit may be bad.

Cylinder leak down test is probably best for diagnosing head gasket failure. Compression check will give some clues.

Do the power windows work then, or no?

The engine is a 2.6 F.I.. The oil pressure gauge works great. It reads about 45 lbs. at approx. 1000 R.P.M.. The engine oil also looks good so I don't think that any anti-freeze got in the block. Thank God. Is the sending unit in the tank easy to access or do I have to drop it? I could always do that if need be. And I should have an extra temp unit around if it is the same as a 2.3? Ihave a few of those sitting around.

The fuel and temp guages can typically be fixed by taking the allen heads out of the guage pod and there is a connector that goes to the back of the guages. Unplug this and give it a look over. If there is any corrosion on the terminals clean it with a knife or a screwdriver. Now put a nice glob of dielectric grease on the connector and plug it in tight.

This fix is two for two. It fixd mine and I forget who the other guy was. Mine were always hit and miss, they workd when they wanted to. After this they worked perfectly all the time.

Joe

I will check that out. Anything easy is the first thing to do I say. If you think about it to hard it becomes a big project. If you know what I mean.