gvthnks

Id take a hard look at expansion plugs while it's out. They're cheap, and a pain to get to with everything in place in the truck

That air filter looks like it's serviceable. Is it possible a lot of this oil residue is simply from an over oiled air filter?

Thanks. Rarely see a renix jeep at the local junkyard, so I may have to buy new.

I have an 87 4.0 with an injector connector that makes intermittent contact and causes a miss. Does anyone know what years of these style connectors are interchangeable? Making a junk yard trek tomorrow and may get some if they're compatible. Thanks

171k on the stock 4.0. After sitting for 11 years, I pulled the engine and head to replace a dead lifter that just wouldn't pump up as well as all of the expansion plugs.

Sweet, thanks

Does anyone have a simple diagram of power flow from the ignition switch through the fuel pump relay, ballast resistor, and to the fuel pump? I'm working on my '87 4.0 / 5 speed. I think my pump is dead, but I'd like to check power along the way before I purchase the bosch unit and going through the trouble. Ultimately, I know I can just check for power at the pump, but I'd like to know the power flow just for my own knowldege. thanks

that may be a great option.

Got mine at AutoZone GP Sorensen 800-9230

Glad it worked out and thanks for closing the loop on the problem.

That looks great.

Agreed. Use a test light, and if it's pulsing, the voltage is most likely fine. Now whether the injector is bad or not and not pulsing like it should is another matter. The possibility of all of them going bad at the same time is remote however so I'd look for another culprit. Spray starting fluid down the intake hose while trying to crank it. If the problem is fuel related, it'll pop, cough and start for a second or three. If not, there are other issues. Have you taken the injectors out of the intake to inspect them visually?

I'm in need of a left tail light if they're available. Would gladly pay shipping and add something for your time.

Just went through something similar with an 87 that had sat for 11 years. Be sure your injector wires are hooked up to the correct injectors. On mine there was enough room for there to be confusion. If it'll run on starting fluid, it's a fuel issue. On mine, I ended up with the head off and engine out to replace all the freeze plugs and lifters but the injectors were so fouled with gunk on the bottom where the fuel was supposed to come out, that even if they were firing correctly, it wouldn't have been good. Like others have stated, check that map hose not just where it plugs into the map sensor, but also where it plugs into the throttle body. Mine was sucking air there too causing issues. Check all the other vacuum ports too and make sure the EGR valve isn't stuck open. Crack the throttle just a hint when you're cranking. I've seen the idle air control valve so badly dirty that it wasn't letting anything through and the engine can't run without air. Cracking the throttle will bypass the IAC and allow enough air in to let it start and run. Clean the IAC and throttle body when you can. Nothing will work correctly if the TB unit is very dirty. As a matter of course, I clean the IAC and throttle body on every one of these engines I work on, cause they're all dirty. Then you've alleviated that as a possible issue and I guarantee you it needs it anyway. Mine would run on 4 cylinders when I first started trying to get it going, but I had to crack the throttle some to get it to crank. That told me the IAC was dirty or non-functional. Easy fix. Lastly, don't fret. If it ran before, it'll run again. Go over Cruiser54's list and read through all the comments on his page. There's more knowledge there that's renix specific than anywhere else I've found. I've had probably 15 of these 6 cylinders over the years but avoided the renix versions. After reading some theory about how it works and the common failure issues, it isn't so bad. The info here has helped me tremendously getting mine resurrected. It's not on the road yet, but we're getting close.