Challenger Posted July 23, 2010 Share Posted July 23, 2010 It's a narrowband. Won't show a number. I'd try to redo your mbc setup. Get your signal from the outlet on the turbo. Also you saic the wastegate moves freely? Is that just the flapper valve with the actuator disconnected or are you talking about valve and actuator still connected moves freely? Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted July 23, 2010 Author Share Posted July 23, 2010 It's a narrowband. Won't show a number. I'd try to redo your mbc setup. Get your signal from the outlet on the turbo. Also you saic the wastegate moves freely? Is that just the flapper valve with the actuator disconnected or are you talking about valve and actuator still connected moves freely? I used to have my boost controller signal taken from the turbo, but started taking it from the intake when I installed my IC. Worth a try to take it from there again just to see what happens. I thought it was best to take it from the intake when you add an IC? The wastegate flapper moves freely when the actuator arm is disconnected, and I've made sure the actuator works correctly by hooking it up to an air compressor. Quote Link to comment Share on other sites More sharing options...
letitsnow Posted July 24, 2010 Share Posted July 24, 2010 Are you actually losing intake pressure or just power? Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted July 24, 2010 Author Share Posted July 24, 2010 Are you actually losing intake pressure or just power? Just power. Boost gauge signal is from the intake, and pressure isn't dropping under boost. I wonder if a video would help everyone see and hear what's going on. I made one but the audio ended up being too low. I might give it another try. Thanks for the help so far guys! We are expecting a baby soon, and I'm hoping to get this figured out before then. I know I won't have much time to play with the car for a while after . Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted July 29, 2010 Author Share Posted July 29, 2010 Figured I would give a little update here on my issue. One of the things I failed to check recently was my timing. I remember setting it several months ago at 20 degrees btdc, but during a lot of searching I came across several threads that mentioned timing for an 83 turbo should be 24 degrees btdc. So I double checked my 83 FSM, and sure enough, 24 degrees. I have a few different FSM's, so I must have pulled up the wrong one when I initially set my timing. So far the car is running MUCH better. I'm hoping that's all it was, but it's proved me wrong before. We'll see. I have a friend coming over tomorrow evening to help me do another compression test. Any thoughts? Quote Link to comment Share on other sites More sharing options...
Zmanco Posted July 29, 2010 Share Posted July 29, 2010 Ignition timing being off by 4 degrees would not cause the symptoms you have described. I think you have something else going on, although I'm at a loss to tell you what it is. You could confirm your theory by retarding the timing 4 degrees and see if the lack of power comes back. BTW, are you sure the FSM says that you should have 24 degrees of advance at idle? That seems like a lot for an emissions legal engine. Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted July 29, 2010 Author Share Posted July 29, 2010 Ignition timing being off by 4 degrees would not cause the symptoms you have described. I think you have something else going on, although I'm at a loss to tell you what it is. You could confirm your theory by retarding the timing 4 degrees and see if the lack of power comes back. BTW, are you sure the FSM says that you should have 24 degrees of advance at idle? That seems like a lot for an emissions legal engine. Yeah, I think I'll take it out around town for a while tonight, and see if it's running consistently better. If so, I'll retard the timing back down and see what happens. Quote Link to comment Share on other sites More sharing options...
Zmanco Posted July 30, 2010 Share Posted July 30, 2010 Sorry, I didn't mean to challenge you on the 24 degrees advance, I was just wondering out loud. I still find that interesting though - the only difference between turbo and NA at idle I can think of is that the cam has a larger LCA (114 degrees vs. 109 IIRC). Anyway, don't mean to hijack the thread off into never never land Let us know if the 4 degrees really made the difference. Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted July 30, 2010 Author Share Posted July 30, 2010 Sorry, I didn't mean to challenge you on the 24 degrees advance, I was just wondering out loud. I still find that interesting though - the only difference between turbo and NA at idle I can think of is that the cam has a larger LCA (114 degrees vs. 109 IIRC). Anyway, don't mean to hijack the thread off into never never land Let us know if the 4 degrees really made the difference. Nah, it's cool . Just figured I would post that from the FSM because there seems to be a lot of conflicting info out there on correct timing for the 83 turbo. Some people say 20, some say 24. Yet multiple people have pointed out that it states 24 degrees under their '83 turbo hood, and obviously in the FSM. Work has had me so busy that I haven't had a chance to mess with the car much more. Been driving it daily though. So far it's running consistently better. No more bucking. Power is back. Air/fuel ratio is still looking good. IDK, things are looking good again. Still gonna check my compression again if I have time this weekend. Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted August 4, 2010 Author Share Posted August 4, 2010 Well, another update for anyone still following this... Car started running like crap again. Did another compression test, and all is good. But I'm noticing a pattern now, which has got me thinking even more that I have an ECU problem. After I disconnect the battery and reset the ECU connections, the car runs great. Give it a day or so, and it starts all over again. Running lean under boost, bucking, and terrible performance. I'll then reset the ECU, and it runs smooth again. Air/fuel looks great. Car runs great. Wish it ran that good all of the time! As already stated, my connectors do not appear to be dirty or loose at all. Neither at the ECU or the harness, so I've never really questioned the ECU before. But now I guess I'm on the lookout for another ECU to try. I'm not ruling anything else out just yet, but I feel like this HAS to be the problem. Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted January 3, 2011 Author Share Posted January 3, 2011 (edited) This should be my last update to this thread. Now I know why the problem I was having was so sporadic. Was messing with the wires to my ECU, while watching my air/fuel gauge, and realized there is a problem on the top plug (the smallest). I would watch the gauge signal bounce around as I touched the wires. I also experienced performance improvements while driving and moving these wires. Just to make sure the problem wasn't inside the ECU, I inspected all the pin's solder joints. No bad joints. So, I got on Z31performance and bought some Z31 ECU connectors with at least 12 inches of wiring. Should feel like a completely different car once I get those old plugs replaced! Edited January 3, 2011 by ransomnotes Quote Link to comment Share on other sites More sharing options...
phil280zxt Posted January 3, 2011 Share Posted January 3, 2011 Please let us know if this solves your problem and how much of a pain replacing the plugs was. I considered doing the same, but the thought of splicing all those wires has kept it on my to-do list. Quote Link to comment Share on other sites More sharing options...
tyler031734 Posted January 16, 2011 Share Posted January 16, 2011 I would like to add a bit-o-knowledge to this. 1983 cars say 24*btdc as there hydrolic lifter cam is 4* more restarted than there 81-82 solid lifter cams, thus the different settings. 20* for 81-82 ans 24* for 83 or so I have been told side note, currently I have mine set to 18* with my 83 motor and still having knocking issues at full boost (10psi) lost a little torque low down, but im going to MSII soon so custom settings to the rescue! Could be the mandrel bent DP, intercooler, slightly ported 75 intake or 60mm TB causing the ECU to be running not so well. Any one in the Portland area want to lend a hand? total newb to MS here... to hand the thread back, Im sure the z31 wiring plugs will help, I see on average a Z a month on roads but rarely get to chat it up with people knowledgeable about there z's, I just feel lonely lol Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted February 20, 2011 Author Share Posted February 20, 2011 Please let us know if this solves your problem and how much of a pain replacing the plugs was. I considered doing the same, but the thought of splicing all those wires has kept it on my to-do list. Check out my build blog in my sig for info on the connector swap. I have only replaced the one plug so far, and the car seems to be running better. Idle has definitely improved, and is much smoother. I don't know yet if this completely solved my issue, but I'll keep updating this thread if there are any changes. Quote Link to comment Share on other sites More sharing options...
zack_280 Posted February 21, 2011 Share Posted February 21, 2011 I had this exact problem with a Z I bought when I was young and dumb. I wish I had seen this thread before I sold it for next to nothing. By the way, you have done an excellent job detailing your problem and progress. Hopefully it will be able to help someone in the future. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 25, 2011 Share Posted February 25, 2011 All your boosts belong to me, sucker Sorry Quote Link to comment Share on other sites More sharing options...
ransomnotes Posted March 2, 2011 Author Share Posted March 2, 2011 (edited) Jeez, what a pain this has all been. Over a year I've been trying to track this issue down. Well guys, I FINALLY found the real problem. Just as I thought, there was an issue at one of my ECU connectors, but replacing it did not completely solve my boost problem. Bought an ECU (thanks Grnsky!) just to see if the problem was my ECU all along, and sure enough it was. Car has been running better than it ever has. Thanks to all who tried to help. It's been a huge learning experience, considering all the work I've put into tracking this sneaky thing down. I'm a happy guy, and so is my z! Edited March 2, 2011 by ransomnotes Quote Link to comment Share on other sites More sharing options...
akeboshi Posted October 16, 2011 Share Posted October 16, 2011 (edited) good to see it fixed. Edited October 16, 2011 by akeboshi Quote Link to comment Share on other sites More sharing options...
jacob80 Posted December 12, 2011 Share Posted December 12, 2011 This is awesome! I'm happy to see that you have successfully solved your problem. The moral of the story here is to never trust electrical connections. Check, double check, and triple check! Quote Link to comment Share on other sites More sharing options...
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