Sputter's Return to Stock

Sputter · Apr 4, 2021

Happy Easter! I’m happy to say that my jeep is finally running!

Replaced the old PCM with one from a junk yard out of Nebraska. It wouldn’t crank so I pulled out the starter and cleaned the contacts. Finally started after 10 clicks. Replaced the starter relay and she fired right up!

Biggest issue was that the fan would not come on at temperature. The OEM pcm seems to have resolved that as the fan comes on and off at 215F.

I have also replaced the plugs, wires and camshaft sensor and it is idling nicely.

Got a small coolant leak I need to track down but I am ecstatic to have this ready for the next phase!!!

Daryl · Apr 4, 2021

Sputter said:
Happy Easter! I’m happy to say that my jeep is finally running!

Replaced the old PCM with one from a junk yard out of Nebraska. It wouldn’t crank so I pulled out the starter and cleaned the contacts. Finally started after 10 clicks. Replaced the starter relay and she fired right up!

Biggest issue was that the fan would not come on at temperature. The OEM pcm seems to have resolved that as the fan comes on and off at 215F.

I have also replaced the plugs, wires and camshaft sensor and it is idling nicely.

Got a small coolant leak I need to track down but I am ecstatic to have this ready for the next phase!!!

Good job on sticking with it. It was certainly a challenging project, good on you for seeing it through to completion. Happy Easter

NDSpeed · Apr 4, 2021

Fascinating thread so far,

en480c4 · Apr 4, 2021

Congrats on the milestone. I’m impressed with your patience and persistence. Looking forward to what comes next.

Sputter · Apr 4, 2021

en480c4 said:
Congrats on the milestone. I’m impressed with your patience and persistence. Liking forward to what comes next.

Thanks. It’s either persistence or listen to my wife complain daily about the POS Jeep that is taking up her garage space!

Sputter · Apr 5, 2021

With new momentum comes new tasks. On the docket for this week:

Find and repair coolant leak - I think this is just a hose that needs to be tightened
Register Jeep - get this thing on the road!
Test drive - code check
Fix pcm connector caps - Minor cleanup
Fix fan relay wiring - Minor cleanup
Finish resurfacing visors & install
Reroute and attach seatbelt sensor - drivers side
Install rear carpet
Install rear seat belts
Clean and install seat rear belt retractors
Install rear seat bracket
Install rear seat cover and seat
Pressure test exhaust for leaks
Take Jeep to transmission shop to repair parking sprag

D M · Apr 5, 2021

Sputter said:
With new momentum comes new tasks. On the docket for this week:

Find and repair coolant leak - I think this is just a hose that needs to be tightened

Register Jeep - get this thing on the road!

Test drive - code check

Fix pcm connector caps - Minor cleanup

Fix fan relay wiring - Minor cleanup

Finish resurfacing visors & install

Reroute and attach seatbelt sensor - drivers side

Install rear carpet

Install rear seat belts

Clean and install seat rear belt retractors

Install rear seat bracket

Install rear seat cover and seat

Pressure test exhaust for leaks

Take Jeep to transmission shop to repair parking sprag

Cant wait to see it done!

Sputter · Apr 5, 2021

4/5 Update
Some more progress today. I fixed the coolant leak and tidied up some of the wiring harness. Hit the ignition and she started right up. Idled smoothly but when I took her for a test drive down the street, she stalled and backfired every time I stepped on the gas. Couldn’t get above idle but I got some new codes so maybe those will point me in the right direction.

P0846 - transmission - I know I have a self-induced problem here. As soon as it is stable I am taking it to a transmission shop.

P0351 - Ignition coil. This code is new and so are the coils so I will need to research this one.

P1494 - Leak detection. I thought I fixed this but apparently not. Still pending and not confirmed though.

https://youtube.com/shorts/UbRWAE6YTRk?feature=share

Sputter · Apr 7, 2021

4/7 Update

Some good news and some bad. Replaced the coil today and the P0351 error went away but still having backfires and stutters when you get around 2000 rpms. Ran through the manual and they say this type of issue can happen due to plugs (mine are new and properly gapped) bad coils or an issue with the PCM. Perhaps the OEM PCM I have is not properly programmed for my Jeep? Hmmm...

Sputter · Apr 14, 2021

4/14 Update

With the PCM replaced, I still have one major issue which is keeping me from getting it on the road and that is when I step on the gas and hit ~2000 RPMS, it sputters, backfires through exhaust and in some cases dies.

Here is my current situation:

P0846 (Transmission fluid) and P1494 (Leak detection). I think both of these are unrelated.
Crank and camshaft position sensors replaced.
New plugs, wires, coil.
Starts up fine. Idles fine. Only acts up when I step on the gas.

Current plan of action:

Replace the gas with fresh. The gas in here is pretty old.
Fuel pressure test at the rail
Replace TPS and IACV
Last recourse: send fuel injectors off to be cleaned

Getting started Friday night. Anything else I should consider or prioritize above these?

Sputter · Apr 17, 2021

4/17 Update

Tested (I think properly) the fuel pressure to the rail. Because it had no schrader valve I had to rig something up. I did not start the engine - just two clicks of the key to run to get power to the pump. Looks like the fuel system does not hold pressure. Hits ~50 lbs initially then keeps dropping. Leaking injectors or faulty fuel pressure regulator?

Sputter · Apr 17, 2021

I measured the pressure when it was running and it was ~49 so good there. In putting everything back together it finally through a open code on the fuel injector. I checked and sure enough, one was loose. I plugged it back in then realized all the locking tabs had been broken off when I re-did the harness. I fired it back up and was able to accelerate to over 2000 rpms without stalling or hesitation. I'm thinking the connectors are vibrating loose and not firing consistently as a result. Can I just rig with zip ties or do I need to cut and replace all the injector connectors?

Sputter · Apr 17, 2021

New developments. I disconnected the negative for about 30 minutes, got in and it started right up. Drove it around the neighborhood for a bit and it accelerated just fine (above 2000 RPMS) no hesitation or stalling. I drove it for about 10 minutes - no issues to speak of.

Then I got it home, turned it off and tried turning it back on. It took 3 attempts to start, then would not accelerate over 2000 RPMS again - backfiring and stalling.

So it appears as though resetting the PCM via disconnecting the battery temporarily resolves the issue for one start? Other systems I am experiencing but I think are unrelated:

I am in limp mode now with transmission pressure switch A and B faults
Heavy, rich exhaust smell in the cab
Check engine light is on (I am assuming it is the transmission codes) and gives generic P0700 code on the odometer.

Additional info - I had problems with the PCM. Had multiple outfits try to repair my old unit but it did not work out. I ended up finding an OEM PCM in a junkyard which corrected some of my original issues with the fan not starting.

Also, previous owner deleted the catalytic converter. So here is my new working theory:

Disconnecting the negative terminal resets emissions monitors and lets it run once. Once I turn it off and back on, it realizes something is wrong with the exhaust and starts stalling and back firing. Going to do a pressure test on the exhaust once it cools down and see if I have any leaks, but I am thinking the lack of a catalytic converter is causing my issues. Going to order a walker universal cat and get that added.

Sputter · May 1, 2021

Ok so exhaust is fine. A couple of leaks and I need a new cat but nothing that would cause engine problems. Started troubleshooting fuel system but that turned out to be ok.
Further research and inspection indicates that whomever rebuilt this engine did not install a tone wheel for the cam sensor so the Jeep never gets out of limp mode. Here’s my thread on that process. https://wranglertjforum.com/threads/leaking-fuel-injectors-or-fuel-pump.49678/#post-860050

While I am waiting on the replacement tone wheel, I will shift my focus to a couple of odds and ends like stripping the fender flares and repairing a fender dent.

I’m hoping to get the tone wheel by Friday and install it to get the engine issues behind. Saturday I will get the cat installed and finish installing the carpet. Then on Monday take it to the transmission shop for the parking sprag. With any luck it will go to paint by the 15th. More to come!

Sputter · May 7, 2021

Got the magic part the other day. Made some progress removing the timing belt. Broke my puller so I had to rent a heftier one from autozone.
Going slow because I don’t want to screw things up and the service manual is different than what I see in my engine.

Looks like I need to pull the exhaust sprocket but I am going to pause for tonight, do some more research and finish it up in the morning.

Sputter · May 8, 2021

Well that was a pain in the *ss. But that was the reason why it was in limp mode this whole time. Took me a while to figure out how to get the timing belt just right but after a few hours of trial and error, I finally got it.
Monday I will get the cat added and the exhaust welded up then take it to the transmission shop to address the parking sprag and the shifting issue.
After that, it heads to paint. A lot of odds and ends in between, but I am over the hump!

Sputter · May 14, 2021

Jeep is back from the transmission shop. Turns out I had a bad TCU causing the transmission to show that it was running at 1076 degrees! Also got them to fix the parking sprag. Jeep now accelerates normally and shifts as you expect. I’m hoping to get the new exhaust in today or tomorrow. In either case, I have plenty to keep me busy before we send to paint.

Sputter · May 14, 2021

Making some progress. Got the rear seat brackets so I cleaned them up, painted them and installed them with the rear seat belts. Also started adding the carpet. Rear seat is going in as soon as I get a couple of bolts from HomeDepot. Steady progress.

Sputter · May 15, 2021

Finished the rear carpet, rear seat and cover. Now I need to add the belt retractors. Also added some extra noico foam to the inside of the doors to help mute some of the rattling.

Sputter · May 15, 2021

A couple more odds and ends while I wait for FedEx to deliver the catalytic converter assembly. I cleaned up and bolted in the seat belt retractors. Chrome was rusted so I used some cola and tin foil to clean them up. Also finished up the metal smittybilt glovebox. Had to change the color from black to tan to match the interior. New taillights showed up but I think I will save those for another day. Time to go drop the exhaust.