Rad_88Comanche Posted July 3, 2020 Share Posted July 3, 2020 Hello there! I have an 1988 Jeep Comanche Eliminator 4.0 (renix) which had been running good, but rich. Being in Los Angeles, I need to pass smog. Upon inspection and changing out some vaccuum lines I figured I was good to go. Two day later, my Comanche hesistated to start, I got her running and drove up to the store -- I pulled over as I think I rememeber hearing a clicking noise cominig from the hood, was idling a bit rough and a puffing a bit of white/grey smoke. I'm sometimes stubborn so I carried on, shut her off and when I went to restart it, it cranked but wouldn't start. I have spark, fuel and I think compression is okay This is what I have done/replaced the past few days: Crank Position Sensor (Napa part, did modification to increase voltage - .4 AC) Replaced Distributer and believe timing is set correctly New Spark Plugs (Champion Copper) and Spark Plug Wires Replaced Starter *(4 months ago) Bosch Rebuild Fuel Injectors *(1 year ago) Tested: Spark Plugs -- blue and hot (getting to all 6 clyinders) Fuel Pressure: 39 PSI Tested Fuel Injectors MAP sensor -- .5 and 4.8 and seems to decrease with vacuum Battery is testing over 12 volts, also tried another battery The #2 cylinder spit out gas when testing compression - pretty sure I ruined the compression tester, the number 2 injector may have been stuck open to cause this, but is now corrected and no longer an issue. I'm thinking possibly Timing Chain may be an issue? Or? Any ideas/advice would be greatly appreaciated. Thank you so much! Link to comment Share on other sites More sharing options...
cruiser54 Posted July 3, 2020 Share Posted July 3, 2020 Did you "index" the distributor? Check the line from the throttle body to MAP sensor. Any cracks, splits, rotted ends and the MAP sees low vacuum. Richens things up. Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 3, 2020 Author Share Posted July 3, 2020 Such an honor for my first reply to be from you as we have been reading all your tips. No we haven’t “indexed the distributer” and cut a hole out of the old cap — will do that. Only did step 12 to set top dead center. We originally replaced the line to the MAP sensor before it wouldn’t start. That was what was odd—we changed a few lines and elbows and then two days later it I’m having a no start. Since then we have swapped them back and forth (from new to old lines and back again). Will focus on figuring out the running rich after we get it running again:) One last note, doesn’t feel like a lot of vacuum out of that hole on the throttle body (that the line connects to) when cranking the engine... Thanks for your help. Link to comment Share on other sites More sharing options...
cruiser54 Posted July 3, 2020 Share Posted July 3, 2020 Tips 1 through 5 are super important to complete. Did you see the Tip on changing the vacuum line at the throttle body? Link to comment Share on other sites More sharing options...
Eagle Posted July 3, 2020 Share Posted July 3, 2020 2 hours ago, Rad_88Comanche said: Such an honor for my first reply to be from you as we have been reading all your tips. No we haven’t “indexed the distributer” and cut a hole out of the old cap — will do that. Only did step 12 to set top dead center. Are you sure you got it at TDC on the compression stroke, not on the exhaust stroke? Link to comment Share on other sites More sharing options...
silvertwinkiehobo Posted July 4, 2020 Share Posted July 4, 2020 He's brought up a good point. My former co-worker did a 4.0 Renix R&R, and somehow got the engine position 180° out. So be sure to check that. Link to comment Share on other sites More sharing options...
cruiser54 Posted July 4, 2020 Share Posted July 4, 2020 16 minutes ago, silvertwinkiehobo said: He's brought up a good point. My former co-worker did a 4.0 Renix R&R, and somehow got the engine position 180° out. So be sure to check that. Tip 12 covers that, but always best to verify. Link to comment Share on other sites More sharing options...
omega_rugal Posted July 4, 2020 Share Posted July 4, 2020 On 7/3/2020 at 1:41 AM, Rad_88Comanche said: I'm thinking possibly Timing Chain may be an issue? take the head cover off and see if the vavles are opening properly Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 4, 2020 Author Share Posted July 4, 2020 (edited) On 7/3/2020 at 4:13 PM, Eagle said: Are you sure you got it at TDC on the compression stroke, not on the exhaust stroke? I believe so—we rechecked it, made some adjustments and still no luck. Followed the indexing (minus the cutout of the old cap), tried one tooth back and forward and still no fire. We have noticed quite a bit of play in the rotor when we rotate the harmonic balancer back and forth (between the rotor and the harmonic balancer). Edited July 4, 2020 by Rad_88Comanche Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 4, 2020 Author Share Posted July 4, 2020 Yes checked for cracks and replaced vacuum line:) Link to comment Share on other sites More sharing options...
Eagle Posted July 5, 2020 Share Posted July 5, 2020 Do you have a timing light? Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 5, 2020 Author Share Posted July 5, 2020 3 hours ago, Eagle said: Do you have a timing light? No timing light handy. I saw that harbor fright sells them for 30 bucks with mixed reviews. I want to keep trying things, but it’s also my daily driver so I’m starting to think maybe I need to bring it to a shop to help diagnose what’s going on. 😬 Link to comment Share on other sites More sharing options...
silvertwinkiehobo Posted July 5, 2020 Share Posted July 5, 2020 You have slop in the rotor and shaft when moving the crankshaft back and forth? I know that Ford's spec for timing slop is no more than 15° rotation before rotor movement. I'm wondering if your timing has jumped at least one tooth? Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 11, 2020 Author Share Posted July 11, 2020 Just giving an update on my crank no start situation. We are going through the mega list, step by step :) Currently on step 2 and eliminating the C101 connector—she was looking real rough! Fingers crossed as I’m back to needing my truck next week 🤞🏼 Link to comment Share on other sites More sharing options...
cruiser54 Posted July 11, 2020 Share Posted July 11, 2020 Hang in there!! Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 18, 2020 Author Share Posted July 18, 2020 Thanks! Just wanted to give a little bit of an update. We finally got around to working on the Jeep again. Changed all the relays and low and it fired right up! I was super excited... changed the oil and put a new filter in it as it had a ton of gas in it (from that fuel injector that was stuck open). Now she runs! However lots of white smoke and water coming out of the exhaust—also does not want to accelerate - backfires a little bit. any ideas? Will continue going through Cruiser 54’s steps as well:) Link to comment Share on other sites More sharing options...
JustEmptyEveryPocket Posted July 18, 2020 Share Posted July 18, 2020 10 minutes ago, Rad_88Comanche said: lots of white smoke Does it smell sweet? If so, I have some bad news about your head/ head gasket. Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 19, 2020 Author Share Posted July 19, 2020 I don’t think it smells sweet...not like coolant, more exhausty.... Link to comment Share on other sites More sharing options...
JustEmptyEveryPocket Posted July 19, 2020 Share Posted July 19, 2020 I would stop and run a compression test, and a leak down test. Make sure you have a good starting point before diving into any other parts + labor. Any auto store should be able to rent you the equipment for "free". I say "free" because you have to put down a deposit, but will get a full refund when you return the equipment. Let us know the numbers and how it reacts on the leakdown test. Link to comment Share on other sites More sharing options...
Rad_88Comanche Posted July 20, 2020 Author Share Posted July 20, 2020 Thanks! Yes! Just got a new compression tester (dry test) today and here is the reading: 1. 130 2. 140 3. 149 4. 148 5. 105 (got 119 and 125 - retested) 6. 115 (130 on retest) unhooked the relay from for the fuel pump, still slight fuel mist from spark plug holes. Stumbles a bit with acceleration (idle is fairly steady), still smoking a little and has black liquid coming from tail pip (seems like oil, but not sure) — doesn’t smell sweet, just heavy exhaust smell. (Like old snowmobiles—lol). :) took a video which will maybe help: IMG_4150.MOV Link to comment Share on other sites More sharing options...
JustEmptyEveryPocket Posted July 20, 2020 Share Posted July 20, 2020 Definitely time for a leak-down test on cylinders 5 and 6. Side question: Why is it always the hardest to get to cylinders?? Every damn time. Anyways, you need to know if the exhaust or intake might be sticking open, or if the rings are shot. Check out THIS VIDEO for a quick overview. His channel is really good in general. I have learned lots watching stuff. At least that is where I would go next. Link to comment Share on other sites More sharing options...
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