budwormy

Hello. New to this forum, but I'm on my second Cherokee, which is a 1987 with barely over 100K on it. I live in Boone, NC area. To make a long story short, I was freshly arrived back in the mountains in May 2020 from a move I was hired to do from Banner Elk, NC to St. Petersburg, Fla. Got back to Banner Elk to drop off rental and go get my beloved Cherokee and jump it because I left the interior light on for the 4 days while I was gone, absent-mindedly. On the way home i decided to take Watauga river road because I was super tired and wanted to go to bed. Unbeknownst to me, there had been a hundred-year flood on the Watauga River (alot can happen in 4 days up here) ,and as I was driving Watauga River Road I stopped at what appeared to be a small section that had a few inches of water flowing across it. I thought about fording it for a moment as said to myself, 'nah, just turn around and head back up and take Mast Gap." Then a young dude in a Toyota pulled up behind me and assured me it was only a couple inches deep for a hundred yards, and I should be fine. I was thinking, 'Man, this ain't **** for THIS jeep.' so unfortunately, off I went. well, turned out it got much deeper til I found myself floating, and headed for the most treacherous water you can imagine. the jeep shut down and water started coming in. There was nothing I could do but not panic, so I figured it was time to bail. I can buy another jeep, but I can't die like this. I climbed out the window to find myself getting sucked into the river, and if you don't know the Watauga it looks pretty peaceful normally, but when it's running hard like that it is death on a stick. I swam so hard I swam out of my shoes and luckily I saw some high ground with a light on. I figured it was my only hope. I had to relentlessly claw at the bank in order to extricate myself from the rapids. Barefooted and stepping all over on 3 inch briars on a steep embankment. Luckily, due to lack of panic and being an expert swimmer, I was able to stay out of the tumultuous current and climb the bank and make my water logged, barefooted worn out body to a nice ladies house to make some calls and get picked up. Had to jump in and swim another football field to even get to my ride, but I was ok except for a bludgeoned sense of pride and sand in my underwear. Lost my banjo, my drone, two good drone batteries, my sons nintendo switch and a bunch of other items, but the beer was OK by the time i got back and an unopened pack of American Spirit cigarettes was floating in the back.
Went back the next day and to my surprise it was lodged in the drainage ditch on the other side of the road away from the rapidly receding Watauga with water flowing about to the Jeep logo above the front grill. Came back later that day and the water had receded to just below the center of the rims. Later that day i had it towed to my house.
Current day: After draining every fluid imaginable and replacing and cleaning all the connectors, here we are. Been trying to get it back running and i feel like I'm almost there. It cranked for about 5 seconds a week ago, and I am currently checking sensors and cleaning everything up I can find. I have replaced the starter and the PCM. I assume the PCM is working because it cranked the other day, and for that short 5 seconds the timing sounded normal (maybe a noob assumption, I dunno). It's from an 89 with the last three numbers '429'. It turns over fine but it seems like it's burning super rich. When I removed the plugs to make sure I had gotten all the water out of the cylinders (which i had done previously by cranking with the plugs out and shooting water 15 feet in the air for 20 seconds), the had to be cleaned and were rather sooty. When I checked the MAP sensor I got my input voltage and ground but there is no juice coming from wire B (signal wire). I've ordered a MAP sensor. The injectors have been cleaned and they all measure a resistance of 16.5 ohms, so I assume (perhaps falsely) that they are still OK. Currently have the throttle body off and waiting on a gasket, after which i will replace and check the TPS. The crank sensor resistance measurement is within the acceptable limits (125-274 ohms), but I haven't checked it for voltage while cranking yet. You can tell the PO replaced it because the wiring route is different. The primary and secondary resistance of the coil measures .8 and 6,700 ohms, respectively, and it fires when I check the plugs and main distributor wire while in the vehicle (it's still out now but i'm getting ready to put it back.) Oh yeah, and I have a new fuel pump, and it primes like it should and good fuel pressure off the rail. The transmission fluid has been changed and neither that fluid nor the oil look like there isn't any water in them. The oil looks normal. I changed but didn't flush the coolant and it doesn't appear abnormal now. It sounds like it wants to start so bad its just aching to, and all my mechanic friends say that they don't think there is anything majorly wrong with the engine, mechanically, when they listen to it turn over. About a week ago, after installing the new fuel pump, it cranked on the first turn over and i almost **** a purple turkey. It didn't stay running but a few seconds, but no weird grindy sounds at all. I am currently checking the remainder of the sensors that i can with a multimeter. (I am already an electrician so I understand electricity and how to measure it and what it all means). Oh yeah, the fuel pump primes when I short the fuel pump relay, too. AND, I took out the tank and cleaned it really well whilst doing the fuel pump. I'm blowing out the fuel lines today just in case there is any schmeg left in them and i have a new filter. I think that's about it up to now.
I was very reluctant to post anything on a site with serious mechanics on it bc I figured I will be met with a chorus of, 'it's over, it's junk, you're screwed, throw it off the mountain', but i consider this a long-term project if need be. I've never done a lot of mechanic work, but after scouring this site for months and getting under the hood, and reading miles of technical manuals, I am fascinated by the science behind all this, and the amazing way all this **** works and is put together. Human ingenuity at its FINEST. I don't really care what I have to do to eventually restore this vehicle to its former glory. Its an 87 which, to my knowledge, is the year before Chrystler took over and the year of the maiden voyage of the 4.0 straight 6, so, even if it is a long term project, I don't plan on junking it. I may be naïve, but I feel like I'm close to at least having the engine running. Any help in this seemingly impossible endeavor besides 'throw it in the ocean' would be heavenly and much appreciated. If i've forgotten to include any pertinent data I will come back and add it later.
Oh yeah, i forgot, it's been converted to open cooling system by PO. All grounds have been refreshed and read .003 or better ohms to battery ground. Moved the battery main ground up to the next engine bolt on right side of block ten inches from the old ground where a few other good grounds are located (torx stud 1/2 inch bolt) and they have close to 0 ohm resistance now, too.
Eliminating c101 connector with soldered, heat-shrunk connections, too. That black tar crap is insane.

aroundincircles

Holy wall of text batman. I couldn't get through it, Please summarize into bullet points of what is wrong.

4.3L XJ

I agree. Cut this down and we will deal with it one issue at a time. And please use standard rules of grammar. Caps at the beginning of sentences etc

budwormy

I got carried away with the setup. I apologize, and I will condense it down for you guys and thanks for responding. A big ee cummings fan.

budwormy

Had a flooding accident. Changed all fluids. Have checked crank sensor, MAT sensor, coil, plugs for spark. All good. Cleaned fuel injectors. Tested for resistance and they all measure 16.5 ohms. Bought and installed PCM off an 89. Its an open cooling system, put together by the PO. Guess that's why I couldn't find the front temperature sensor. MAP sensor shows no signal voltage, but the input and ground are good. Refreshed all grounds and they all read .003 Ohms or better. New fuel pump. Fuel pump relay worked if I short it I can hear the pump come on. Gas tank has been removed and cleaned thoroughly. New fuel filter. Crank no start (maybe MAP sensor?). After installing fuel pump it cranked for the first time and cut off after a few seconds, and hasn't started again since. i've tried a few more times. Ordered a new MAP sensor. Throttle body is currently off, getting a gasket here in a minute. After that checking the TPS, and I've cleaned the IAC pretty well along with the throttle body. Oil looks normal. Transmission fluid looks normal. When I checked the plugs for spark they were very sooty. Sounds like it's just about to start when cranking but just won't. Hopefully that's enough, but that's where I am.

4.3L XJ

So you have verified you have spark?

IJM

I'm just glad the beer was OK!

budwormy

Spark is good. Checked it visually on each plug and even on the main wire going to the distributor. Did a bench test on coil and got .8 and 6800 ohms on primary and secondary windings, respectively. By the soot on the plugs looks like it's running to rich to start. When i crank it it just sounds like it's right there. After installing the new fuel pump it cranked for a few seconds and died. I checked the crank sensor for resistance and it was within the limit (170 cold not running). Checked the MAT sensor today and it was reading proper resistance for the temperature. The coolant temp sensor has been moved because the PO installed an open cooling system, so I think that changes to a sensor controlling the cooling fan, which I found today but have yet to test or even know how to. Like I said before, the MAP sensor has input (solid 5V) and ground but no signal voltage, and I traced the signal wire to the ECU and verified continuity on it. All ground have been re-done and they all read .003 ohms or less.

4.3L XJ

Is your crank position sensor working?

doublechaz

MAP is critical to deciding how much fuel to inject. Try again after you get that working.

lawsoncl

Fuel pump ballast resistor intact? TPS sensor doesn't like getting submerged, but it's easy enough to test with a meter or just unplug it and see what happens. Good battery voltage, as the Renix doesn't fire the ignition if the cranking voltage is too low. Also pull the coil off and clean the contacts underneath (guessing you did it you measured the resistance). Don't give up. You'll get that purple turkey yet.

1990

One thing I would check if you have not done it yet, is to check to see if you got water in the fuel tank. With your XJ in that amount of water for that long I would not be surprised if some gone in. Also did you check all the electric connections in the engine compartment and interior?

budwormy

I already took the tank out completely and cleaned it thoroughly. Took the coil out last night and primary and secondary resistance is within limits. Getting a nice, big blue spark. MAP sensor is definitely kaput, but my wife is ordering one for me tonight. Crank position sensor is working. Got a resistance of 175 on it and the plugs are firing. Getting good fuel pressure, it just won't start. It's crazy. I checked the TPS today a la cruiser tip, and it tested good. Not sure about the IAC but I did take the throttle body off last night and cleaned it up and the IAC. New gasket and what not with some sealant. All grounds are testing .003 ohms or better. Checked all the fuses today as well and none are blown. The accessories all work. Lights, wipers, and what not. When I crank it it just turns over and hits now and then and seems to just flood. You can smell the gas. The temperature gauge goes up to redline as it turns over, that might be a clue. I found the sensor for the cab gauge, but since the PO added an open system cooling system not sure where the ECU send temperature sensor is. It seems like its just choked to the max to me, but I am by no means a mechanic. That paradigm supports the bad MAP sensor diagnosis. Its on the way, but I spent the whole day tinkering around with it. I actually soldered the CPS wires together because its been changed recently and you can tell the routing is after market for the wire. The connector was really wambly so I figured why not. I'll keep ya'll posted once the MAP is in. It just seems like its choking to death. Oh yeah, the fuel pump ballast resistor was removed by the PO. There two Bosch relays over where it once was mounted that I'm clueless as to what their purpose is.

Idunno

http://www.lunghd.com/Tech_Articles/...lse_Stator.htm

budwormy

That was gonna be next.