August 5, 20177 yr Author comment_527458 Alright, finally checked fuel pressure. 37psi before starting (starter solenoid disconnected) and sat about 32 while idling. Bear in mind it currently idles at about 1k rpms. I disabled the cold start valve by plugging the line, to no effect. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527458 Share on other sites More sharing options...
August 5, 20177 yr comment_527461 Double check your firing order since there was confusion in the beginning. TPS is not supposed to move like that, http://atlanticz.ca/zclub/techtips/tps/index.html Use a timing light. Check your PCV valve and hose. Edited August 5, 20177 yr by gwri8 Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527461 Share on other sites More sharing options...
August 5, 20177 yr Author comment_527463 I've done the timing with a light already. The TPS certainly is designed to move like that, it's the range of adjustment. I just finished adjusting it properly following that link. Firing order is also correct. I think I'm finally onto something with the following: I have a spare fuel rail, complete with injectors. I swapped injectors on the half of the rail where the "clean" plug was, then used my stethoscope to listen to each injector. Cylinders 4-6 (the new injectors) were far louder than 1-3. In fact, number 6 made number 1 sound like it wasn't firing at all. I'm going to rig up an injector cleaner and come back with the results. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527463 Share on other sites More sharing options...
August 6, 20177 yr comment_527471 When I was a teenager my Dad and I rebuilt my '76. He's all American when it comes to cars. He did the firing order like a straight 6 Chevy. No go. Talked to a buddy and swapped the wires around and Boom, ran like a champ until I totaled it. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527471 Share on other sites More sharing options...
August 6, 20177 yr comment_527485 In your first video when you finally get it to fire it sounds like you have an exhaust leak. Is your egr tube connected? and tight? Also runs like a firing order issue. Double check firing order like mentioned above. Or mixed the injector connectors? If it was mine I would double check all vacuum lines / vacuum leak sources, and firing order. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527485 Share on other sites More sharing options...
August 6, 20177 yr Author comment_527489 EGR seems to be bad from what I can tell, it doesn't seems to be holding vacuum. I've got a spare that does, so I'll swap that on. Firing order is correct, I've redone it several times to make dead certain. Another idea: When I set timing, I put the crank with the mark lined up exactly at 0 and then inserted the distributor shaft in at the correct orientation (small side of shaft towards the front, pointing to 11:25AM). Now I'm reading something about needing to set it to 20 degrees BTDC? I also saw to read the sticker inside my hood, but it seems to have fallen off. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527489 Share on other sites More sharing options...
August 6, 20177 yr comment_527492 I set my 80 ZX N/A to 20degrees before tdc. Also, have you verified that your oil pump shaft is properly indexed? Edit: 12 degrees before TDC Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527492 Share on other sites More sharing options...
August 6, 20177 yr Author comment_527494 Found the problem! EGR valve had a rock stuck in between the plunger and the housing. Swapped in the new one and she just purrs. My dad thinks it has a perfomance cam in it too, but I have no idea since I lost the rebuild paperwork. Thank you everyone for your help. I'll upload a video of it finally running shortly. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527494 Share on other sites More sharing options...
August 6, 20177 yr comment_527495 Congratulations! Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527495 Share on other sites More sharing options...
August 6, 20177 yr Author comment_527498 45 minutes ago, siteunseen said: Congratulations! Thank you! Feels great to finally have it back to life. Here's the (crappy) video: Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527498 Share on other sites More sharing options...
August 7, 20177 yr comment_527516 Excellent! Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527516 Share on other sites More sharing options...
August 8, 20177 yr Author comment_527537 Alright, now I've got a new problem. The throttle was sticking when driving, which I tracked down to the BCDD. I tried adjusting it but the adjustment screw didn't do anything, so I jumpered the sensor wire to 12v on the ignition coil which fixed the problem. My concern is that idle is at about 850 with the idle screw all the way in. Is this a problem? I recall reading that it should be set to 5 and 1/2 turns out from screwed fully down. Link to comment https://www.classiczcars.com/forums/topic/58265-rebuilt-engine-idle-problems-running-rich/?&page=2#findComment-527537 Share on other sites More sharing options...
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