noelawinslow Posted September 6, 2013 Share Posted September 6, 2013 I'm running a 78 with a turbo swap, and mostly everything is done. I suspect timing, but I really just have no clue what to look for. After dropping the engine in, I got the ecu, maf, harness, and o2 sensor all working. No codes on the ecu except AC. The ecu is an 87 cali turbo 5spd model. Before, I had it running reasonably well on 370cc injectors, but for tuning sake I decided stock was more my choice. Now it barely runs. Some positions on the accelerator keep it alive, and messing with the timing exacerbates or alleviates the issue, but it's not consistent. I altered the timing to get the car to run on the 370cc injectors but now I just don't know. I BELIEVE I reset the timing according to the FSM, with the tang at 11:45 on 1@TDC. But I'm not sure where to go from here. If pictures and/or video are desired I can do that tomorrow. Quote Link to comment Share on other sites More sharing options...
tooquick260 Posted September 6, 2013 Share Posted September 6, 2013 Will be interested in the responses. Did you follow FSM diagnostics? Will it idle? If trying to rev from idle does it bog/spit? How did it run on the 370cc injectors? If it did not run good, then you have either wiring/connections, ecu, injector problems. I am in the middle of this same install. My car would idle but not read the maf I was using. Once i figured that out an got the ecu to read the maf, car ran great! Until a ground wire for the ecu came loose and I lost the driver in the ecu for injectors 1,2,3. Things I checked to diagnose my problems. Ecu signal- check ohms on pin 5 to ingitor, making sure you have continuity Maf signal- check volts out, should be 1.5-1.6 with ignition on not running, 2.0 volts when idling and go up to 5+ volts when reving. Injector wiring to ecu-check ohms at the injector back to the ecu, 87 ecu I think is high impedence should read 14 ohms, my 3 bad ones read 003 ohms, if you have noid lights you can plut into the injector connectors and see the signals O2 sensor- check volts on the signal, i don't remember the proper voltage but you can look up in FSM for the 87 ecu, nicco forums FSM is great and easy to look up Injectors- check ohms on each injector FSM again will give you info Good luck Quote Link to comment Share on other sites More sharing options...
noelawinslow Posted September 6, 2013 Author Share Posted September 6, 2013 All of the injectors fire. Continuity exists between the ecu and the ignitor. I swapped mafs as well (forgot about that) because my maf was drilled out and adjusted for 370cc injectors. I'm not running an O2 sensor yet, but the Z should still be able to run fine without it, right? I hear it's not even used until a number of criteria are met. I pulled my maf from the junkyard. Maybe I'll go back and pull another one. It's likely this one is bad. Everything else in that car was. I'll test the maf and see how it comes up. Quote Link to comment Share on other sites More sharing options...
LuvZBoost Posted September 9, 2013 Share Posted September 9, 2013 Any luck?! I'm super bummed that we're all kind of having the same problems at the same time. I'm suspecting my ecu might be bad. I really don't want to throw parts at it without knowing for sure though... Quote Link to comment Share on other sites More sharing options...
SDgoods Posted September 12, 2013 Share Posted September 12, 2013 (edited) I went through all this Car sat for a couple months as I had a lot of other stuff to do but these systems are still relatively finnicky. Took me a while to figure out. My advice... I made the mistake of leaving the air filter off the maf, make sure you put a filter on the maf/intake.... the maf does not like the turbulent air and after I put mine on it helped immensely as it did another member who did the same thing... Make sure you have The constant + voltage to the ECU for the ECU memory. It was not in the right up I used and I discovered it just comparing the s130/z31 wiring diagram. Were your guys cars running alread before the z31 stuff swap? I'm running fine with no 02 sensor and no burn cycle on the maf (although I still plan to wire it in)... make sure injectors 2 and 5 are switched for batch firing. Make sure if you have 81, the dropping resistors are removed. Have you all verified fuel pressure? If you have a wide band are they running rich or lean? Edited September 12, 2013 by SDgoods Quote Link to comment Share on other sites More sharing options...
noelawinslow Posted September 13, 2013 Author Share Posted September 13, 2013 Turns out it was a massive vacuum leak at the blockoff plate for my egr bung. I've fixed it and the engine has smoothed out a LOT. Now the fun is in figuring out what's causing this random grinding noise. The engine misses regularly sometimes around 2500 and up, but stays pretty close to stable at idle. It's so close to perfect I'm losing my mind. I've been running it without the filter, so now I'll be adding that to the mixture to see what becomes of it. I have to figure out how I'll plumb the CAI now, since the MAF doesn't sit as close to the hole as I'd like it to. I may have to take a hammer and smash it in. Has anyone come up with a reliable way of stuffing that in line with the hole in the radiator support wall? The next issue that's popped up is a VERY random grinding noise, similar to the sound of someone engaging the starter while the engine is running. I can't seem to locate its origins, but I'm going to check valve lash and run a compression test just to see the state of this engine. I never got the chance to because it was dirt cheap and sitting in the back of someone's shed for several years. It's quite possible the block is bad, but I somehow doubt it since it feels like it wants to run right. Just a gut feeling. It's also running a bit hot according to the gauge, but I've yet to check the accuracy of the gauge now. Is there a way to check a/f ratio without an emissions check? Quote Link to comment Share on other sites More sharing options...
SDgoods Posted September 13, 2013 Share Posted September 13, 2013 (edited) Turns out it was a massive vacuum leak at the blockoff plate for my egr bung. I've fixed it and the engine has smoothed out a LOT. Now the fun is in figuring out what's causing this random grinding noise. The engine misses regularly sometimes around 2500 and up, but stays pretty close to stable at idle. It's so close to perfect I'm losing my mind. I've been running it without the filter, so now I'll be adding that to the mixture to see what becomes of it. I have to figure out how I'll plumb the CAI now, since the MAF doesn't sit as close to the hole as I'd like it to. I may have to take a hammer and smash it in. Has anyone come up with a reliable way of stuffing that in line with the hole in the radiator support wall? The next issue that's popped up is a VERY random grinding noise, similar to the sound of someone engaging the starter while the engine is running. I can't seem to locate its origins, but I'm going to check valve lash and run a compression test just to see the state of this engine. I never got the chance to because it was dirt cheap and sitting in the back of someone's shed for several years. It's quite possible the block is bad, but I somehow doubt it since it feels like it wants to run right. Just a gut feeling. It's also running a bit hot according to the gauge, but I've yet to check the accuracy of the gauge now. Is there a way to check a/f ratio without an emissions check? Glad you got it figured out for the most part. I would just buy a wideband 02 sensor with the gauge... Theres a guy selling AEM Uego on here for 157 shipped brand new. I have the same one and I love it.. You can just run it straight on its own, I use mine every day I guarantee it will come in handy, especially on a modified/swapped car. http://forums.hybridz.org/topic/114817-aem-wideband/ Edited September 13, 2013 by SDgoods Quote Link to comment Share on other sites More sharing options...
noelawinslow Posted September 15, 2013 Author Share Posted September 15, 2013 Best part is, it was the turbo making that noise. Now I have to go find another t03. Quote Link to comment Share on other sites More sharing options...
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