Boltjd

Alright, I'll give that a shot. If this is the case, would I replace the ignition switch entirely? Or just the specific wire running to the pin or connector running to the coil?

Alright, well you seem to have gotten the point either way. And yes, I have upgraded engine grounds with the exception of adding an additional ground for the fuel pump (tip #29). Do you have any other idea why there seems to be an 'open loop' (probably not the correct term, but I'm sure you'll correct me haha) which is 'closed' by plugging the underhood light into the ignition coil? Unless it's just a matter of adding additional grounding reinforcement. I actually have not added an additonal ground from the negative battery terminal to a bolt on the chassis above the radiator.

Hey everybody, I've got a 1988 Comanche Pioneer 4.0 and I've had some trouble with an erratic/rough idle since acquiring it a little over a year ago. It's my daily driver and a bit of a project truck, so I've spent a lot of time restoring it myself. To give some background, this includes new injectors, TPS, CPS, IAC, MAP and O2 sensor, water pump, radiator (as well as converting from closed to open cooling system), water pump, fan clutch, power steering pump, steering box, steering shaft and harmonic balancer. I've also put in a new camshaft, lifters, cylinder head + head gasket and intake/exhaust manifold gasket, as well as new motor mounts, a new fuel pump an. I've installed new coil springs, ball joints, hubs, front and rear shocks and struts, rotors, calipers and pads, even a dual diaphragm booster and updated master cylinder (as well a as well as a clutch master cylinder) rear drum shoes and hardware, steering linkage and pitman arm, and track bar. I've refreshed the grounds and done a few tune ups, including replacing the distributor, ignition coil and ECM. I even put in an ECU from an '90, per Cruiser54's tips, and even an updated MAT sensor (albeit with a slight modification, as it's basically impossible to find an OE MAT). I've done quite a bit of soldering, whether that includes installing new connectors or pigtails for almost every sensor and every fuel injector, and even refreshing some of Chrysler/Jeep's horrific duct tape 'connections' (photos attached). Okay, *phew*. So, to the point, a few months ago, I started to experience (at first) intermittent stalling, usually at stoplights, coming to a stop (as one does), and it was concerning, but it would usually start back up after a couple terror-ridden minutes (the truck would crank, but not turn over). Then, one day, it didn't start back up. I had it towed to a local shop, and upon arriving at said shop, I was told that there was a plug that was not plugged in. I was shown a red wire with a connector that I had not seen plugged into anything since buying the truck: I had assumed it was an extraneous connection, probably utilized in a higher option submodel, as the wiring harnesses seem to be universal to each submodel. The mechanic plugged the connector into the ignition coil, which then switched on the fuel pump, seeming to turn the vehicle into 'accesory mode'. He told me that unless I jumped it to some point, I would have to plug and unplug the connector each time I started and then stopped and got out of the vehicle, or my battery would be drained. I've been doing this, and the truck has been running without any stalls since, at the expense of having to plug in and unplug every time I get in or out of the truck. I've scoured wiring diagrams, and it seems that the plug is either the connection for an engine bay light, or an 'ETR' fuse. It runs to the starter relay by way of a green fusible link. Any ideas what this could mean? Any solutions? Also, any ideas what might be causing the rough idle? Possibly a vacuum leak I'm unaware of? (I've also replaced the vacuum lines and I have completed a cylinder compression test, all to satisfactory reading.) I'm at a loss.

Hey all, I just spent a good amount of time installing new ball joints, hub/bearing assembly, axle u-joints, and steering linkage (Rough Country HD Upgrade). After putting everything back together, I got in and put it into first, and the truck does not seem to want to move forward. There is a grinding sound coming from the front axle/differential and it seems to be seizing. Please help me troubleshoot this!

The first photo is very confusing to me, as there are a series of wires once connected to the anti-theft box that lead through the fire wall, fuse at the black box in the second picture (the links are pictured at the bottom, slightly to the left, next to the MAP sensor connector), which splits at the horn, and then breaks off into a black wire which contains an odd fuse plug-thing which is pictured in the original post and ends in a ground which was grounded at the ignition starter relay. The third protrudes from a loom passes near the charcoal canister. The fourth photo is right off of the C101 connector; I assume it is a diagnostic connector or something. Any help is appreciated.

The next series are two connectors that come from the harness connected to the fuse box. I do not know what purpose they might have.

Thank you for the quick replies and apologies for my belated response. I appreciate the link to Cruiser54's website. I've got some pictures of some connectors I'm concerned about and can't easily find identification. This first series shows a relay and connector which to me does not seem original, but when I unplug the relay, the accesory power turns on, but the vehicle will not turn over. The loose wires came from an anti-theft box I removed, and the other three striped wires split a green wire, and the other seems poorly soldered into a yellow wire. As I mentioned in the original post, the original owner installed a kill switch, which was hooked up to a lock cylinder in the drivers side fender, and the wire connected to it is green.

I need some help here. I have a 1988 Comanche Pioneer 4WD M/T and I'm trying to clean up the wiring harness under the dash. There are qiite a few connectors that are missing their 'mates' and it concerns me. I did take out the HVAC box, due to a leaking heater core and a botched removal job, so it could be a few connectors that were once attached to those. Also, the first owner crafted a 'kill switch' and did somw of his own modifications. I also removed an anti-theft device (Clifford IPS box), and I wasn't sure if that was OE or not. I've added some pictures, and if anybody answers, I will take some more tomorrow and post them. There is in particular, a white connector, a fuse holder that seems to be coming from the horn/anti-theft light behind the dash, which is grounded to the starter relay, a connector with 4-pins and 4 wires, one of which (black/tan) was cut off, and a Bosch relay connector that seems to have one of the blade terminals bypassed, so that there are only 4 out of 5 blade terminals and two are connected by a black link. I've scoured wiring diagrams online and I've had no luck. Any help is appreciated!

I think the coolant temp sensor, which is on the thermostat housing, is responsible for changing fuel/air mixture and thusly engine timing based on temp, while the sender on the back of the cylinder head connects to the temp gauge. So I don't think that would be good. I really just need to know the correct color of the wires that hook up to the connector so I can solder it back.

Hello, I'm new here, so forgive me if this post is redundant. I recently acquired an 88 Comanche 4.0 4WD and the previous owner had installed an aftermarket temp gauge, which seems to be hooked up to the thermostat housing coolant temp sensor. I've noticed a misfire during idle, which I've tried to remedy by way of a tune-up, replacing the entire distributor, MAP, crankshaft position, TPS, and checking my cylinder compression, which reads at about 150 psi for each cylinder. I stay up at night racking my brain for solutions, and then, I realized it might the after market temp gauge. The sensor attached to the thermostat housing seems to be modified with a wire that runs along the valve cover, through the fire wall, and directly to the temp gauge. I'm wondering if the modified temp sensor and possibly the temp gauge/bulb is not grounder well enough and if this could cause an intermittent misfire. I also looked at the wiring harness under the dash, where the fuse box is located and it is a complete rat's nest, with a few connectors unplugged. I was also wondering if anybody would be able to send a photo of a relative clean "area" to give me an idea of what connections are possibly missing. There isn't much online other than confusing wiring diagrams and I'd like to clean it up. Help is much appreciated.