Los_Control

Just WOW!

I have not checked all cylinders ... I feel swapping coils should mark the coil off the list .... then replacing the electrical wiring to coil also. I have heard many times to always buy sensors from the dealer for oem parts. I have no idea if OEM is still available for a 32 year old vehicle. ... I have no dealer anywhere near me to purchase one. When I installed the engine I replaced coil, wires, plugs, crank, cam sensors... Replacing the brand new crank sensor was the first thing I tried .... so I have tried 2 new crank sensors and nothing changed ... while it is still possible, kinda doubtful. I tried a experiment yesterday .... unplug the MAF and then take it for a drive and see if problem disappears. It idled too fast so I never did drive it ... I let it run and warm up. I believe after it was warm the computer went into closed loop and it ran like total crap. .... I plugged the MAF back in and it ran normal again. Also CEL came on without MAF, went out when plugged back in. So I now think the computer is working properly and is grounded. Over on the Chrysler minivan forum I have been getting some good suggestions, most all of them has been covered from this thread already. Seems the injectors are color coded for different engines/years. The current engine came with orange injectors and the engine came from a car. I installed the black injectors that came with the van ... it was easier. So next move will be to swap injectors .... I doubt it will help. Seems I tried everything else, may as well swap them also .... they do have less miles on them then the current injectors. I decided to work on the truck over the weekend. Have it back on blocks and ready to paint the last 2 wheels. The new turn signal switch arrived so I can finish the wiring on it .... install new tires on Monday. Change injectors on Tuesday.

Hang onto your hat @Sniper wind gust up to 60-65 mph tomorrow. I can try the heat gun and see what happens ... pcv looks normal. Someone is suggesting bad injectors .... I might have to follow that route and see what develops. I have always carried the original fuel rail over from original engine to the next .... they now have 190K miles on them. I first want to test the two other sets I have before installing ... no problem buying new, but if I could verify first it was the issue .... Either way ... off to cook dinner and wont even poke my head out the door tomorrow ... take care all

Best I can figure is heat at this time ... early on I could not reproduce it in the driveway at idle ... as it slowly gets worse, I can reproduce it in the driveway at idle. It has a MAF, IAC, TPS .... I tried unplugging the MAF ... it was a disaster. The engine idled too high to drive .... then when the engine warmed up and computer went to closed loop ... it ran like crap ... no way to drive it with maf unplugged. I do wonder about that though ... 3 years ago the original engine blew up with 2 rods through the block and the pistons had broken ring landings and rings .... oil went everywhere including into the plenum. If you stick your finger into the plenum it will come out oily and black with soot .... Is that normal? Is it possible the engine warms up and the goop inside of plenum is causing a issue? I just figured it was almost 4 years ago and will sort itself out .... I always used the same plenum from original engine because it was working at the time.

Swing and a miss! Cleaning up the wire harness was time well spent, I believe. I'm a lot happier with routing and I replaced the coil wires so there is no doubt on them ... It runs exactly the same though. I made a video this morning on what the spark looks like when it is running right. As @Sniper pointed out, the engine fires on every stroke so it looks really busy ... it is steady and strong and the engie runs correct. This is a really poor video, but if you use your imagination ... you can see the spark is not steady and is erratic and fades in and out while the engine cuts out. ... this is after driving it out of town and back to get it to act up. As @Ivan_B suggest and others ... it can be a bad sensor or a corroded wire that is telling the ECM to act this way .... I dunno, kind of out of ideas for now.

Thanks @Sniper It does help ... I have also heard about the wasted spark before. When the engine runs smooth, it is really busy showing spark .... then it fluctuates from there. I have been asked if I tested power wire going into the coil to see if it was steady ... also power coming out of ASD to insure it is steady. I finished up my wiring on it today and think it is all pretty clean .... still need to add some zip ties to it to be certain it is all out of the way. Wife says we need to do our monthly shopping tomorrow .... dogs are out of ice cream .... I may not get it running tomorrow after shopping ... maybe Thursday I will have it running again and know if anything I did helped? Installing the plenum is a real pita with the braces and connections under it, that can not be seen during installation.

Sometimes we just have to pick the battles we want to attack. Knowing it is the side curtain physically holding it up .... I got no clue. Can you sneak a hook into the front of it and try to pull it back? Possibly if you can just move it 1/8" the headliner will come down a 1/8" and split the difference? Again, maybe if you let it sit for awhile and relax, both pieces will move and settle down. I remember years ago installing a trex deck ... plastic decking when it first came out 30 years ago. It was a wrap around deck on 3 sides of the house and at least 100' long at the back of the house. We meticulously took our time and chalked lines and we laid those plastic boards down dead straight. At the end of the day we put our tools away and we wanted to admire our work .... that 100' run the boards looked like snakes in the hot afternoon. We really went home thinking we would have to pull it up and redo our work. The next morning was nice and cool, those boards were straight as a arrow. ... later when hot, looked like snakes again. With my experience, plastic expands, contracts a lot with heat ... it just moves. Myself, I'm still thinking about a colorful Mexican blanket for a headliner .... someday.

I remember watching that link awhile ago when it was posted .... there were a few things I did not agree with, I did think the guy was very knowledgeable. I also was reminded about how old men like to sit around and tell stories 🤣🤣🤣 The story about the camshaft was what caught my attention .... never in my years have I heard that.

I fully understand that. Possible the ASD is cutting spark also ... even then, every physical part has been replaced or tested. Including the ECM ... the only thing left because of my shotgun approach is the wiring. So at least the coil wires will be eliminated and everything else will be out in the body harness to check. Thanks for the tip on the forum link, I will take a look at them .... I belong to a few forums, Dodge forum is one. They are kinda lost when it is not a Dodge truck with OBD2 and live data to read ... but a good bunch of guys to chat with. I also have my daily driver chebby truck and hang out on the Silverado forums ... good bunch of guys and some good mechanics .... OBD1 ... forget it ... not many out there that care enough to drive these old rigs, and familiar with them. And I'm taking a crash course on learning my way around them

I feel sorry for you ... it has been a ongoing saga. I took a break from working on it recently and took time to think about it ... we just continued to drive the car around town. It has progressively gotten worse and for the first time I was able to create the situation in the driveway. Just using a in line spark plug tester I was able to monitor the spark going to one cylinder. When the engine ran smooth the spark was fine and steady .... at times the engine would act up and the spark turned very erratic or sparse ... sometimes there was no spark at all and engine died at a idle. I now know without a doubt, it is a spark issue and not a fuel issue. The engine has a cam/crank sensors and 1 coil with 6 plug wires coming from it. I replaced the crank sensor twice and no change, same with coil, it has a new ASD relay. I feel more then I know, it is losing power to the coil ... I should have done more testing on it to prove it. I still do not trust the wiring harness where it cross over the exhaust ... at one time the loom came loose and got hot. With the extra wire harness I have around, they all have repairs in that area. On this harness you can see 3 wires have some black shrink tubing with a yellow stripe on it. A previous repair where the harness crosses over the exhaust .... other people have had wiring issues in this area ... I have another harness and it also has repairs .... My original harness so far has no previous repairs done to it. Everything works with no issues, except erratic spark going to the coil. In the photo is a plug and 4 wires for the coil, I will cut my coil wires out and replace with a different one all the way from plug to plug. I spent the day inspecting and looking at all the wiring and since everything but the coil is working right ... I'm just going to wrap it back up and put everything back together ... with new coil wires. I'm hoping that will fix it, but prepared to accept it wont .... I will not have to wonder about condition of harness because it is inspected.

Hrrmm, I was thinking a good sunny day and get some heat to it ... it might relax and fall into place. Possible a hair dryer to warm it up ,,, I have a heat gun, it gets too hot imho. A hair dryer I would be scared to try .... but a sunny warm day on the roof where everything gets heated up at the same time. Drop it off over to my place for a few days ... will be in upper 70's-80's all week. Or grab a cold one and leave it as is.

I wonder if over time it will relax and settle down to where you want it to be?

@Ivan_B There is no CEL on, last time I checked there is a stored code for running rich ... that does not trigger the cel though. It is randomly losing spark to the plugs ... so when a cylinder cuts out and still getting fuel ... makes sense it is rich. Currently what I'm looking at .... still getting the body harness opened up. Because the way the spark acted ... I think it has to be the wires that power the coil, or possibly in the wiring for the ASD relay. .... A bad ground could also be at fault. I have what is needed to replace the coil wires from the coil end and will have to splice and solder into the main plugs in the photo. I'm still concerned about other wires in the harness ... they are hard and no longer flexible because of heat from the exhaust .... while they still function and do what they should ... I will feel better to cut out the damaged and solder in new. Another example of what I'm finding .... The factory clips that hold this harness up, broke long ago. the harness runs the full length over the header and is melting the plastic covering protecting the wires. So I'm just going to spend a couple days going through replacing wires and making things better then before. Good chance I might not fix it this way, a chance I may fix it .... at least I will know the basic harness is in good shape, while now it is questionable, and a future problem. As a side note, the 2 extra harness I have, already have previous repairs in the same area ... the one installed is a virgin and never repaired ... I may as well keep and repair it.

Not suggesting it is ideal, the narrow belts work fine on the wider pulley's ... So if the crankshaft pulley was narrow you could just run a narrow belt. ..... My 1950 218 engine has wide pulleys. Previous owner had installed a newer generator with narrow pulley and ran a narrow belt .... I replaced that with a alternator and still running a narrow belt. You could not run a wide belt on narrow pulley, you can run narrow belt on wide pulley. Find out what the guy's bail is .... maybe pay his bail and get your parts back and let him work off bail with labor?

That particular area I always had a bad feeling in my gut about it .... I really would not be surprised if that is where the problem is. Because I plan to change those wires and fix other possible issues at the same time .... I will never know if it were those wires, or possible grounds or other things I fix.