JefCooks

Plugs are dark but not so much that I would consider it extremely rich.

So I hooked fuel pressure gauge up again and cycled the fuel pump. This time it was not holding pressure. Pressure would climb to ~40 with ign on but then drop rapidly. I have a fuel pump on hand and am trying to install it but I don’t have a spacer to fit the new smaller pump to the assembly. Any tips on where to source one or a part number? Thanks everyone

I had already purchased a new ignition coil, rotor and cap before this happened so I decided to install them and see if that helps. I checked resistance on the Accel coil before install and everything was within spec. I also checked signal to the coil while it was out and got good signal. Once everything was in I grounded spark plug on block and cranked it. I AM getting spark so next thing is to go back and check the fuel again. I’ll update later.

I was looking for the best way to check for spark. Is there a way to use my multimeter or should I just pull a plug and stick it in the block while cranking?

Also, CEL is on and gives codes 12 (battery disconnect) & 22 (coolant temp sensor). Since I know I have fuel pressure at rail, could it be a throttle position sensor or something similar that might cut off signal to injectors? I can hear the fuel pump when I turn key (rather loud) and when it dies it doesn’t buck or sputter, it just dies.

Holds pressure for at least a few min

Hi everyone, ‘92 4.0L aw4 3 days ago I replaced my factory battery cables with a Big 7 from JeppCables.com. I also replaced my factory alternator with a 140(?)A alternator from a v8 ZJ. Upon initial install the truck wasn’t starting. It would crank no prob but wouldn’t run. I checked the relays, cleaned the fuel pump ground behind taillight but no go. I discovered that the ground I installed to the block was loose so I tightened it and everything worked but it was idling low and surging a little bit. This smoothed out after I left it running for a bit. I drove it the next day and had no issues then the following day (yesterday) I stopped at the bottom of my driveway to get the mail and when I took off it stalled and I couldn’t get it to start again. I primed the fuel pump a couple times with no luck, then randomly it fired up with me pumping the gas. I got it home and it was running fine. Right now the truck is my only transportation so I drove it to work today (I can defend my logic if you care) then to the parts store to get a fuel pressure test gauge. Upon leaving the store truck stalled, I primed it a few more times, it fired up and I headed home. I got to the bottom of my street and it died so now I’m stuck here waiting on the car gods to let my truck work for 5 more minutes so I can get it home because I can’t find a pattern to this. Here’s what I know so far: The fuel pump turns on when I turn the ignition Fuel rail gets pressure up to 40 something psi and keeps it for at least a minute All grounds are secure Truck only dies when not giving it gas I have a fuel pump & filter that I was going to install on Thursday but since it builds pressure fine I’m not sure that’s it anymore. It definitely FEELS like a fuel issue but could it be an ignition issue? Any help at all would be immensely appreciated. Thank you all Jef

I got it working again! And....I feel like an idiot. While waiting for the new starter I pulled the battery and set it on the trickle charger. The new starter came in, I swapped it out, hooked up the battery and still nothing. At this point I decided to start over and go from least complicated to most complicated. Having been to the JY recently I came home with an abundance of fuses and relays so I decided to replace all fuses. Still nothing. Then I decided since I was there I'd just fill all the fuse and relay locations, even the ones that don't work, so that I would have spares handy. Then the truck started. Evidently, when the IOD fuse went (see first post), so did the 40A ABS fuse. I mindlessly pulled the ABS fuse and tossed it because I don't have ABS then immediately forgot that I had done such a thing. It turns out that my ABS fuse is not for ABS, but a fuse betwixt the solenoid relay and the solenoid itself. Now the truck is running great again and all is right in the world. Thank you to all who helped and to all who may read in the future, check ALL fuses and relays, even if it doesn't seem applicable.

SWEET!! I knew she was a rare bird but that's pretty unique.

I tested the battery and it had full charge. I also did not leave the ignition on the whole time. Owning a 30 year old truck; if the engine is not running, the ignition is not on. When I pulled the starter I bench tested it with my running diesel Grand Cherokee and the negative hooked to mounting the ear. The starter spins like new but the solenoid does nothing. I'm going to the JY today to get a. 8.8 for a wrangler I have and I'm gonna get a solenoid from an XJ while I'm there to use in the interim while waiting on my warranty solenoid from Rock Auto. Once I get home I'll test it out and let you all know.

Here is the general format: 1992 Jeep Comanche 4.0L, AW4, NP231, D30 Front, 8.8 Rear, Long wheelbase Build date: 03/92 Current Location: Santa Cruz, CA Status: Still on the road (usually) Notes: Originally maroon paint (faded to dark purple then painted eggplant), skid plates, column shift, gray cloth bench seat, aftermarket winch front bumper, 4.10 gearing, 16" XJ wheels, 255/85r18 tires, small fuel tank Current owner: All mine

UPDATE: I think I figured it out. I pulled apart the PDC and everything was in order. Followed all wires and they all had power when they were supposed to. So I got under the truck and tried to jump the starter again like gogmorgo mentioned. I connected power to the solenoid post and it clicked but then retracted and all power in the truck went out. I pulled battery terminals off and let it sit overnight. This morning I went back out, reconnected the battery and everything powered up but still no crank. I got under the truck and pulled the starter off to bench start it, nothing. The starter motor still works fine when connected directly but any power through the solenoid stops dead. The starter and solenoid are a Bosch reman unit under warranty so they're sending me a new one. I'll update this thread once I get the new solenoid in. TL;DR: I think it's the solenoid

Yes, it does. The + battery clamp has 2 large wires feeding directly off the clamp. One goes to starter, the other goes to PDC. You're right. I was just reading a NAXJA page and found same info. I'm gonna try to jump the solenoid rather than just the starter motor. Thanks so far everyone!

I haven't because I was hoping it would be something else and I wouldn't have to pull the fuse box apart. I guess I'll have to do that next.

So there's nothing on/in the interior fuse panel that would affect the starter. I put the multimeter to the engine bay relay/fuse panel today and found that the relay gets the 12V signal from the ignition but there is no high power feed to or from the relay. My battery cables don't have a ton of corrosion on them but I'll pull them off and try again. Anything else I should check? What are my next steps? Please don't tell me to pull the engine bay panel apart.

Hey fellas, I need some help with my '92 Comanche w/ 4.0 & AW4. Last week I refurbished my parking brake which entails pulling the driver side fuse panel. Once I got everything back together I turned the truck on, it fired right up like normal and I took it around the neighborhood to make sure everything was as before. A few things were wrong, radio didn't come on, dome lights didn't work & headlights didn't work, so I turned it off and started checking into some things. The IOD fuse in engine bay had blown which caused the radio and dome to not be working unless engine was running and I had to reconnect my headlight wiring. Once I got that all squared away I went to turn the truck on again and it wouldn't crank. I checked all the fuses, relays, battery is fully charged, tried it in neutral, nothing is working. The starter will spin when I get underneath and bump it but nothing from the ignition. When turning the ignition I can hear the relay charging but nothing goes to the starter. This leads me to believe the issue is with the starter solenoid but I don't know where to start because I replaced the starter and solenoid with a Bosch unit 2 years ago and repaired the coolant leak that was dripping onto the starter causing the first one to go out. Also, before replacing the first starter I cleaned and lubed the NSS. The extremely sudden change in functionality makes me think it's electrical but since I can hear the relay working, it makes me think it's in the starter. Please help me diagnose.

Just to close up the thread, I figured out the problem and repaired it. The next time it wouldn’t crank, I checked the battery o nextions and fuse, all good. Then I got under the truck and tried to jump the starter solenoid. It sparked, but didn’t spin. Bingo! While under there I found the heater core valve had a very slow drip right onto the solenoid. So, got a new starter & solenoid and am going to replace heater hose with the 97+ direct run hoses. I was baffled that it was the starter given that it was intermittent, but I guess the coolant would cause a temporary short??

The cables all look good from what I can see, no corrosion and solid attachments. My plan was to check the voltage as previously suggested and jump it to see if that’s it.

Ok, I’ll try and get it to happen later today and keep you posted. Thanks.

Hey everybody I have a 92 4x4 4.0 AW4. Sometimes (randomly) my truck won’t start, it won’t even attempt to crank. It’s been happening for several months at this point, but I don’t drive the truck much so it feels quite frequent. It’ll start fine at home but if I go somewhere and the engine warms up, it won’t turn back on after shut down. 2 months ago I cleaned the NSS and it hadn’t happened since then but then happened yesterday. The headlights don’t dim when I’m trying to start it so it’s not a bad starter. The lights and fuel pump kick in when the key is turned so I don’t think it’s the ignition switch. The grounds don’t look terrible, but which ones should I inspect closer? Any other insights? Thanks everyone!

Do you have a closeup if the Hood? What did you do about the center channel? OP, I’ve been thinking about these but would really like something with a drip rail. http://rodlouvers.com/Jeep-XJ-Louvered-Aluminum-Hood-Bolt-On-cooling-panels-Cherokee-Comanche-louvers-P4921315.aspx

Thanks for sharing! OM617 is happening when my engine fails. Hopefully not too soon.

Hey everyone. Wanted to give an update to close out the thread and let future people know what worked for me. Pete was 100% right. I had the original 6 blade fan and it worked, but I never heard it kick on and off, nor could I hear it when the engine was running like on other vehicles I have. So I decided to swap it out with a newer style 10 broad blade style I got for cheap on eBay. It worked! I can sit in traffic with A/C on and it stays around 210 in 90+ degree heat. I can even park it with ac on and have a quick bite to eat without it getting anywhere near what it used to. I know it’s not 195, but with a few pieces (near rad cap, hood vents, etc) I think I can keep this thing from cooking itself. If anyone is hesitant about buying a new fan, I can say 100% that the fan upgrade is VERY beneficial. Thanks for the suggestion Pete, and to everyone else’s help, suggestions and questions.

Thanks! I’ll check it out when I get back for vacation. Happy 4th everyone!

I had the condenser out 2 weeks ago when converting R12 to R134. Its clean and can see through easily. No excess dust, grass or mud.