AnotherOldJeepGuy

Great, and that makes sense. I'm going to assume for now at least this alignment has not changed since before whatever it was that happened, happened.

Yeah, I have read through those instructions about 10 times, but I get lost at about step 7 (well assuming I could get past Tip 12, and not very confident on that either) Given this, is there any logic to the thought that what I did could have changed this?

Took Jeep in to a second shop for more diagnostic assistance, this is a shop I used before for a muffler, and the primary mechanic has been there for 30 years, so he actually has seen this engine. I let him know all the stuff that has been done, and also that at least one goal was assistance looking for vacuum leaks. He pointed out two things before smoke testing. One was the injector harness connectors looked corroded and not very tight. (This could relate to the REM readings about injectors). He actually was able to pull them off without loosening the retainers, I don't know that you should be able to do that, but he did with no trouble. He recommended they be replaced. Rock Auto sells them for about $8 each. The other was that he found one of my new plug wires arcing at the plug end boot to a vacuum hose (the one that goes to the heater control valve) that decided to rest next to it. So he suggested that wire also be replaced. My wires are new, I suspect I poked a hole trying to remove them when I pulled the plugs out a week ago, but still I guess I'll replace that one. I find it hard to believe either of these failures are a result of the maneuver incident, but since I have not given up that my truck will survive this yet, so might as well fix what needs fixed whether it has anything to do with the bigger problem or not, particularly if they are fairly easy and inexpensive. Then on to the smoke test. He introduced the smoke at the port just in front of the throttle body, the one that normally connects to the hardpipe going to the back of the valve cover. We let the smoke build up for a while and the only place any smoke came out was the airbox. My assumption is that location is OK, I am assuming the airbox is not expected to be completely air tight. The mechanic didn't seem to be concerned about the smoke there. We saw zero smoke anywhere else. He raised the truck up so we could also look from the bottom, and still no smoke. So unless the smoke entry point used is not valid, there does not appear to be any leak in either manifold or the gasket. I asked about the potential of timing being knocked off by my truck-killing maneuver. The plan is for me to go forward with the items above first, then once they are complete and if they don't fix the issue, I'll take it back and he will break out the timing light and check the timing. My guess is, I will be taking it back for that timing check, but if the items identified here do fix it, I'll take the win. @Gojira94, I'd like to hang on to the REM until I put on the new injector harness connectors if you don't need it back sooner. Would be nice to see if the INF errors disappear.

Tried the reset procedure, no change

I think I kinda get it. The throttle "opens a big hole" on purpose to the outside air and that would cause the vacuum to drop. I didn't think about that. I tried plugging off the line to the brake booster back on April 10 (hard to believe this problem has now been in place for almost 2 months) and nothing changed, but some improvements have been made since then and maybe it's time to repeat that test.

Remember the vacuum plug? It is still there. So I decided to see how much different the vacuum reading would be if I connected the hose back. At idle it was ~17 (I captured it at 14.5-15.5 earlier with the plug in place). This isn't much different so it seems to say that I don't have a vacuum leak in the lines supplied by this hose. The REM doc says opening the throttle should lower the vacuum? This seems backwards to me, I would expect the vacuum to increase. Case in Point: In the past, from time to time a crack would develop in the vac line that goes into the firewall and supplies vacuum to control cabin air flow, and when it started to develop a crack, the airflow would switch in part at least to the defrost, and at that point, increasing my engine RPM, the airflow would return to the cabin vents suggesting vacuum had been temporarily restored (increased) by the higher RPM. So this sounds like more RPM increased vacuum rather than lowering it. And also right now, part of my problem that resulted from "the maneuver" is my power brakes are loosing assist, more-so at low RPM, that is to say increasing RPM restores brake assist at least some degree, which again suggests more throttle = more vacuum not less. So I don't understand this at all!!

Thanks, I have been avoiding any time on the highway but it might be worth it to go do this at least once. It doesn't really mention how long a battery disconnect might be to require this, so the assumption would be I guess that any amount of time counts.

OK I finished my homework before the heat come back outside. Pulled 3 lugs at the block ground point, plus the primary ground cable. The primary ground cable is relatively new and still looked clean, the other three were not terrible but for sure have been improved now. I scuffed them clean with sandpaper, also the point of contact with the block. Then gave them a bath of contact cleaner. After the cleaner dried I put it back together. I cycled about 6 times turning key to RUN and OFF, checking codes at each RUN position. I saw I3 no ground detected the first time, then every time after that I saw "No Injector 12V” + “KO Tests Not Run”. I did try wiggling the connection at I3 and the harness, that didn't change anything. I never saw any complaints other that I3 during this limited test. I started up and watched the Knock count, first letting it idle for a minute or so. I did see it toggle to 1 and back to 0 occasionally at idle. Then I bumped it up to around 2500 RPM, +/`100 I guess and I saw the knock counter report from mid-20 to mid-40. According to the REM doc, 10-100 is normal at that RPM so based on that I assume my results are OK, and also I am assuming without any way to know otherwise, the knock sensor is reading correctly. After this just for grins I disconnected the battery for about 30m for an ECU reset then repeated everything above after the ground cleaning. After the ECU reset, switch between OFF and RUN (not starting) about 6 times. Never saw the Injector ground open reported, but I did still see "No Injector 12V” + “KO Tests Not Run”. Once I saw “KO Tests Not Run” by itself and once or twice I saw ECU report No Errors. Then I started up and looked for knocks. Results very similar although the knock count seemed to be a little lower hitting upper 30s. But I realize this is a sampling of knock counts so I don't know that "a little less" means much especially since it is still in the range noted as normal by the REM docs. For future reference, how long is really needed for an ECU reset? When I disconnect battery I have been disconnecting both cables and shorting them together help bleed off everything.

Gotcha. So at locations 1-3 I have 1 old and 2 new injectors. There is one thing unique with 1-3, the ones that have from time to time thrown the fault, they are probably the ones farthest from the ground lug based on how the wires are routed. I'll try the knock test above then clean up that ground connection, and see what happens. Probably be tomorrow morning cause here in Texas it's already too dang hot by about noon for me to do a lot of work out in my driveway!

How are the injector numbers assigned? Is it 1 through 6 from back to front, or front to back, or an assignment related to firing order? Across the multiple readings I have gotten when I did see the INJ error, I saw I1 the first time, then I saw I2&I3 a couple times after that. I installed 1 new injector in Feb '25 to replace one that was leaking even after new o-rings. 2 others were replaced by a shop maybe a year earlier. So I have 3 relatively new and 3 original as best I can recall all apparently working fine until my maneuver. From back to front, if that numbering is 1 through 6, then I1, I2 and I4 would be where the original ones are, and the other 3 are new over the last 2-3 years. If I knew how the numbers are assigned I could relate the failures to all old, or all new, or a mix.

Here is what I saw for those readings. I am not expert enough to know if these meet the criteria of falsely reporting lean or not. or what would cause that to happen... It is interesting that LT says the ECU is "using the Base Fuel Curve (I think that means Open Loop) while ST says it is not. I have no idea what that means, but it seems like it can't be both. I ran the engine for a while and watched the readings that indicates Closed, to see if they changed, I didn't see them ever change from reporting closed.

Got a new one good through July 3... 340611031172570460

Continued with the soap bubble test. This time I soaped up the connections at the Oxygen sensor and the pipe between the exhaust and intake manifolds. And as much of the rest of the exhaust manifold I could get the soap sprayed on. Still no bubbles. I have probably gone as far as I can go with the soap bubble test, I don't think I can get to any other spots. If there is a crack, it either can't blow a bubble or it's where I can't get to. I studied the REM documentation a bit more and found that it says when the sensor is operating properly the reading should constantly swing between a high and low value, and mine is doing exactly that (1.7-4.8). And it seems so unlikely to me that the 'maneuver incident" could have caused my relatively new sensor to go bad, but it is another test case I can try since @Gojira94 generously lent me a oxygen sensor for the test. I did go back and check my Rock Auto order and the sensor I installed in Feb '25 was NTK 23553 Oxygen Sensor.

Rain Stopped so I collected the engine running dataset and added to PDF. Note that since TSP was showing low I adjusted it to 17 before collecting the additional information. My expertise doesn't let me identify good/bad but I don't see much that is obviously way out of line based on the REM documented expectations. I guess I am most curious about the readings that kept moving around, because the movements coincide with the engine revving up and down during idle, and it didn't use to do that (IIRC). REM Gauge Readouts Engine Off-On.pdf

Thanks for that confirmation, I figured but the warning was not clear!

I collected everything I could find that lined up with the "REM Gauge Readouts Summary" with engine OFF before I got chased in by rain. I got the reading through the menu HOME->DIAG->READINGS and noted them in a copy of that list which I have attached here. I got an error when I attached it, or at least a message, telling me that pdf was not supported? I am guessing with no knowledge that the error means it calling be displayed in the thread, but I am assuming the attachment can be opened by anyone that can open a PDF. Can someone confirm it can be opened so I know posting a PDF works or does not please? Looks like there are other sub-menus but I don't have any REM for Dummys book to follow to know what other buttons I might need to push or in what order, so I am hoping this gets me where I need to do. I'll update and repost with a version annotated with the same reading with the engine running after the rain. REM Gauge Readouts Engine Off.pdf

OK, I got some info. I am far from an expert at using this tool yet and I am trying to figure out the button driven menu system, but my first attempt I get the following: REM installed, Key ON, engine not yet started. CODES: -REM CODES --No REM Codes -ECU CODES --Injector 1 Open (this was not consistent, I later read instead I2 and I3 Open, but not I1) According to the documentation on the website, "ECU does not detect Injector # wire has a ground path" -TCU CODES --No TCU Codes. -ABS CODES --Not Available. Then with engine started. CODES: -REM CODES --Loop Fault Lean According to the documentation on the website, Possibly faulty o2 sensor, weak fuel pressure, other fuel system imbalance. – TIP: This code is more common during cold weather starts as the first Closed Loop attempt may fail due to the Cold Fuel Enrichment value still being too high. This code can be ignored if the 2nd closed loop attempt succeeds -ECU CODES --No Injector 12V** (This was consistent, but is to be ignored**) --KO Tests Not Run **According to the documentation on the website, if "No Injector 12V" is received along with "KO Tests Not Run" it can be ignored. -TCU CODES --No TCU Codes. -ABS CODES --Not Available. Once I can get more familiar with the menu I'll try to grab the other items listed by @Gojira94.

Great Find!

When I first switched from r12 I was not impressed. That was quite a while back. It never seemed to have the same bite. Over the years I have gotten maybe 3 new compressors and sometimes they worked great, sometimes they were just OK. So I guess to answer your question, if your replacement is done right, and the components are all good, you should expect your AC to be almost as good as the r12 was as far as I can tell. If it isn't, you have an issue with parts or the install, or both. I have a spike thermometer stuck in my center vent because it was feeling a little less effective last summer. I added just a little Freon and it got back to normal or a least close to it. When outside is in the 80s or less it probably hits low 40s, as the temp goes up as we are quite familiar with both living in TX, it can't keep 40, but the delta from outside is still around 35 or so.

Awesome, I'll be watching the mail! Thanks again!

I just did soap test #2, I suds-ed up all along the top of the area where the manifolds connect and again saw no signs of any bubbles being blown, or soap being sucked in, and also no sign of RPM changes with the soap and then as I rinsed it off. This is not too surprising since the water testing has already proven to not show anything, but it was another place to try the soap that was easy enough to get to. Now I need to let it completely cool again and see if there are other places I can soap up and try again. I am not loosing track that everything was great until the "maneuver incident" so although I cannot yet find any crack, a physical issue still seems more likely (at least to me) rather than some control that failed coincidentally at that same instant. I have read over the distributor index posting at least 4 times at this point, and have not come to a sufficient understanding of that task to pursue it. It may be beyond the extent of my mechanical grasp, time will tell.

I got my last ones at Advance Auto Parts in Jan '25 when my local store was closing, sorry I don't have the PN. I don't remember them being anything different than OEM, so however many holes the OEMs have, these have, and they work fine.

Good info thanks. But luckily I don't believe I need a replacement, at around mid-80 degrees the resistance was around 2k, which I now know is an accurate reading. BTW I did try starting up with it disconnected just to see if I noticed anything different, I didn't. Then I reconnected it.

I just typed the ohm number even though I realize now I specified I used used the k-ohm scale. The correct statement would have been ~2.06 k-ohm. Sorry for the misleading post....