WahooSteeler Posted February 21, 2021 Share Posted February 21, 2021 If doing an EGR delete does anybody know if the Dorman 090-061 plug used on the intake also fits the bung on the Renix manifold? Or what size plug would fit there? Link to comment Share on other sites More sharing options...
cruiser54 Posted February 21, 2021 Share Posted February 21, 2021 Pretty sure they're the same/ Link to comment Share on other sites More sharing options...
WahooSteeler Posted February 22, 2021 Share Posted February 22, 2021 5 hours ago, cruiser54 said: Pretty sure they're the same/ Thank you sir! Looking at pics they seem the same and logically you would think so since the tube is the same diameter at both ends. Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 1, 2021 Author Share Posted March 1, 2021 Alright I closed off my EGR and I also managed to snag a Mopar 4713639 oxygen sensor. I can’t really tell a difference in performance after doing the EGR. I also replaced the new vacuum connector line that was on my FPR because it was split. the oxygen sensor swings a lot faster and is more responsive. Before putting in the Mopar sensor it would struggle to keep closed loop when I let off the throttle because the ST would go to 0 before the O2 sensor is able to respond in time. Watching it, I could see it was slow to respond. The new Mopar sensor is a much better and almost never fails out of Closed loop because it’s so much faster and catch the O2 swing before ST fails. Buuut, she still idles around 20 ST. I checked my butterfly valve and can fit a piece of paper between the valve on throttle body. I was concerned she was getting choked for oxygen, hence the low O2 numbers. I don’t think that’s the case though. after changing in the 746 injectors my idle has been around 1050. Before it was 750. My tps is 16 so I’m a bit stumped with the idle. Seems like a vacuum leak, but I can’t find ANYTHING. I did another propane test today and realized that even if I put it into the intake, I don’t hear the idle change. What I do see is the O2 readings stop swinging and read low. So I was watching the REM while doing propane tests and didn’t see anything indicating a leak. Link to comment Share on other sites More sharing options...
87MJTIM Posted March 1, 2021 Share Posted March 1, 2021 What is your LTFT? ST is based on the LT settings. IF LT is above 128 (lean), then ST will read below 128 (rich) with a properly functioning fuel system. The ECU sets fuel injection pulse width based on the LT settings. The ST readings will signal to the ECU to adjust LT downward. Ideally, the ST should bounce above and below 128, while LT remains at or near 128. Link to comment Share on other sites More sharing options...
JMO413 Posted March 1, 2021 Share Posted March 1, 2021 How long in one drive have you drive it? My runs like crap if the ECM gets reset. After a nice long drive all is fixed. I don't know where and can't find it again but some where I read the Renix ECM needed 20 minutes at above 40 MPH to learn. I sure wish I could find it again. Link to comment Share on other sites More sharing options...
Ωhm Posted March 2, 2021 Share Posted March 2, 2021 35 minutes ago, JMO413 said: I sure wish I could find it again. I found this procedure. 88 FSM Computer Relearn Procedures.pdf Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 2, 2021 Author Share Posted March 2, 2021 Thanks for all the info there. It looks like manual is a simpler ecm relearn process. I still need to take it for a long drive, but it looks like I've developed some sort of parasitic draw on my battery because it's been dead when i go to start it the last two times. Never had this issue before the last week. I'm thinking that my ECM was reset when i had to jump her to get her started because my LT was back at 128. It was down at 120 last week, but like I said I don't drive her much. I'll spend some time pulling fuses to find where the power draw is coming from. I'll make an effort to take her for a daily highway run. I have only taken her for two 40 minute drives in the last month, but the battery was reset after that I believe. I had always assumed that the ST and LT were related but not dependent on each other. If you're constantly running with an ST at 50, I assumed that LT would slowly start dropping down to 50 but I guess I was thinking that the LT only impacts Open loop? If ST is at 50 when LT is at 128, Would it be expected for ST to change if LT dropped down to 50 as well? Like is the ST +-128 from whatever the LT point is? Example: After an ECM reset, ST was at 50 and LT was at 128. If I take it for many long drives and the LT drops down to 50, what should the ST be at? Would it still be around 50 or would it be closer to 128? Does it function like this? Assuming LT sets the base fuel usage and when in CL, ST adjusts fuel usage from the LT point? That would be awesome if that was the case... Open loop - LT = Fuel usage Closed loop - LT+ST = Fuel usage Link to comment Share on other sites More sharing options...
87MJTIM Posted March 2, 2021 Share Posted March 2, 2021 If the ST is 50 and LT is 128, the ECM will pull the LT down to bring them to equal. It senses a rich conditions. As the LT drops the ST will increase trying to lean out. Eventually, the two will be (should be) equal. If LT is <128, the ST should be >128. The ECM will then increase the fuel to reach balance Link to comment Share on other sites More sharing options...
Ωhm Posted March 2, 2021 Share Posted March 2, 2021 6 hours ago, PhilisDiller said: If I take it for many long drives and the LT drops down to 50, what should the ST be at? Would it still be around 50 or would it be closer to 128? Both ST and LT fuel trim only adjust INJ PW time (mS) during Closed Loop (CL) operation. Numbers greater than 128 increase INJ PW time while numbers less than 128 decrease INJ PW time. Now how they work together on my part here is a guess. So my guess is whichever way ST is trending, LT will follow that trend, but the goal of LT is to keep ST number at or around 128. If LT can't keep ST around 128, LT will adjust itself again and again until ST reads near or about 128. Could be why ECU needs so many types of drive cycles for its re-learning procedure. Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 3, 2021 Author Share Posted March 3, 2021 Good stuff! I think you're right. I did a test today and can tell you with certainty that idling does not "teach" the ECU. The LT stayed at 126 after 30 minutes of idling with an ST around 30. I took her for a 25 minute drive on the freeway and before I even got halfway, my LT was at 105. While cruising, my ST is almost perfect! Pretty much floats at 100-110 the whole time. The ONLY time my ST doesn't look great is at idle. Everywhere else is just beautiful. I haven't done any long term mpg testing yet, but looking at my speed and GPH, I was getting around 22mpg on flat highway and even 16-17 going up hills. And she could mostly maintain her speed in 5th gear going up hill. The only last thing i'll do is get exhaust fume smog testing done for my own personal knowledge of her polution levels. I'm really happy and will probably leave the engine as-is for now and will start focusing on the windshield leak, detailing the interior, replacing ripped seats, fixing rust, getting my keys working (I don't need a key for my ignition and I don't have doorlock keys). Thanks a million for all the help. It's been a bumpy ride but I'm a happy camper Link to comment Share on other sites More sharing options...
87MJTIM Posted March 3, 2021 Share Posted March 3, 2021 On 3/1/2021 at 3:20 PM, PhilisDiller said: I also managed to snag a Mopar 4713639 oxygen sensor. May I ask where you found this "un-obtainium"? Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 3, 2021 Author Share Posted March 3, 2021 There were a few on eBay for $91 so I grabbed 2. I have a feeling I’ll be owning an 2 door renix XJ in the future. 😈 there’s 2 more on eBay but they are $121. Ouch Link to comment Share on other sites More sharing options...
eaglescout526 Posted March 3, 2021 Share Posted March 3, 2021 1 hour ago, 87MJTIM said: May I ask where you found this "un-obtainium"? There is supposedly one left at a dealer. Link to comment Share on other sites More sharing options...
87MJTIM Posted March 3, 2021 Share Posted March 3, 2021 9 hours ago, eaglescout526 said: There is supposedly one left at a dealer. How does one fine this? What does it cost? How does one order? Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 5, 2021 Author Share Posted March 5, 2021 A 88 renix XJ just popped up at my junkyard with the same blue color interior. I’m going to grab anything that looks good and am wondering if anyone had recommendations for things that I need to grab while I have access to a renix? Link to comment Share on other sites More sharing options...
87MJTIM Posted March 5, 2021 Share Posted March 5, 2021 The list is too long. Is there an online photo of it? Cruise control system? throttle body, sensors, instrument cluster, etc... Link to comment Share on other sites More sharing options...
PhilisDiller Posted March 5, 2021 Author Share Posted March 5, 2021 Dunno about cruise control. I need some interior bits and was planning on grabbing all the sensors/solenoids. Also need the window seal for both front sides. I'll snag the mirrors too and maybe drop the towing mirrors. Dunno which route I want to go there yet. I'll keep my eyes peeled for axles too. What's the reason for the throttle body? I thought people upgraded to the HO TB? Link to comment Share on other sites More sharing options...
89 MJ Posted March 5, 2021 Share Posted March 5, 2021 Grab that silver dash bezel, those are fairly valuable. Grab the seats (if they aren't too bad), armrests, armrest trim, tilt column, front bumperettes and maybe front bumper, the dash if it isn't cracked. Honestly, grab everything you can afford to. Link to comment Share on other sites More sharing options...
JMO413 Posted March 5, 2021 Share Posted March 5, 2021 https://youtu.be/cwFYRzcTZHs Here's mine today for what it's worth. Link to comment Share on other sites More sharing options...
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