Over30S130 Posted February 24, 2011 Share Posted February 24, 2011 Heys guys, this is probably going to be a little long, but here goes. I've been searching this site for about two years now and have been absorbing all the good info. obtained along the way. I initially joind to learn more about these cars due to having purchased a '79 280ZX that was not running at the time so I took her down to halfway restore as a project. I have since bought an '82 Turbo that I couldn't pass up as my daily driver. The only thing major wrong with it so far was that it occasionaly sputtered on start-up. I found out some things that I thought I would share as well as also to maybe get some suggestions. It has always had a low idle of about 650 and has stalled out one time. When the RPMs are revved to about 1500 to 2000 constant-there is a slight miss noticed which may account for the low idle. I filled up at about 1/8 tank the first day I had her and for the first two days afterward-wether it be cold morning start-ups or afternoon start-ups, it would have no power for several miles. Once any load was applied to propel her down the road, she would immediatley sputter and bog down and if I tried to compensate by applying more gas pedal it would start to pop through the AFM. Backing off the gas would stop the popping, but the car would still have almost no power. It took a couple of days to figure out that when this happens, if I completely let off the gas and then steaily reapply that the power comes back-could this be a sticky AFM? Also the car will surge/miss slightly when under light load, but runs strong under boost. Two days after filling 1/2 tank that first time, I could not get her to crank one afternoon on first try as she usually does, so I drove another car. The next morning I tried cranking, only longer this time and even messaging the gas pedal and finally got her to slowly crank with a little bit of black smoke out the tail pipe. I turned her off and she fired right up again, but with low idle still. I turned her off again and decided to wiggle the AFM connector and ECM connections. The next start-up that afternoon it seemed like the lack of power problem had went away-I was able to get on the throttle right away. Occasionally the fuel pump will make a little more noise than usual when idling and I am wondering if I might have some trash in my tank as well, afterall the car has 155,000 miles in which 141,000 were acheived by 1998 so the car hasn't been driven a whole lot in the past 13 years, but is in very good shape-original engine and turbo. Car came with good records and as far as I can tell the fuel pump has NOT been changed, but injectors have been due to leaking or bad flow pattern and FPR was changed as well. The car is probably in need of a basic tune-up which will hopefully cure the slight miss and low idle? I am going to install a pre-filter to the pump and run some Sea Faom through the tank as well. I have not had a chance to do a compression check, but that's on the list. One other thing, it has a viper alarm that has had the horn disconnected, but the alarm light still blinks, when I cut the ignition off, the engine still runs for a split second and then the engine check lights flash and then the door locks open-Is this normal or could it have to do with the alarm wiring? BTW, the ignition switch was the last thing to be replaced along with new battery-will look into stronger battery, better cables(although new) and check grounds given info. on here about problems in these areas. A/C does not work, 2nd PO said it need compressor and 1st PO istalled Hayden electric fan. The whole fan/AC thing has me wondering-I have to dig into that one. Not sure if fan was replaced before copressor went out or because it went out. I have my ZX back after 25 years(Turbo this time)and thanks to Hybrid Z to help me keep it running. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted February 26, 2011 Share Posted February 26, 2011 (edited) Go through all the EFI (should say ECCS) harness wiring and check/clean ALL the connectors (including the connectors to the ECU). (bad, dirty, oxodized, non-existant connections account for a LARGE portion of the problems with these early EFI systems) There are relatively simple tests listed in the FSM to check all the individual ECCS components: AFM, Air temp sensor, cylinder head temp sensor, O2 sensor & all the rest... Edited February 26, 2011 by cgsheen Quote Link to comment Share on other sites More sharing options...
Over30S130 Posted February 27, 2011 Author Share Posted February 27, 2011 Go through all the EFI (should say ECCS) harness wiring and check/clean ALL the connectors (including the connectors to the ECU). (bad, dirty, oxodized, non-existant connections account for a LARGE portion of the problems with these early EFI systems) There are relatively simple tests listed in the FSM to check all the individual ECCS components: AFM, Air temp sensor, cylinder head temp sensor, O2 sensor & all the rest... Thanks for the reply. I wouldn't have known to check connections if it hadn't been for this site. I might have been like others and throw time and money at it and some have gave up and sold there cars I'm sure. Any recommendations on best(?)connector cleaner that is readily available-would only like to clean these once at this time if I can help it. I've heard of CAIG Deoxit, but don't know where to get it. I need to change my plugs to see if that fixes my 500 RPM low idle and ever so slight surging while mildly accelerating, but not sure which plugs to buy-heard that one can't go wrong with NGK, but wondering if there is any benefit to spend more on the platinums or go cheaper, but just as good perhaps with the U-grooves. Quote Link to comment Share on other sites More sharing options...
Ruiz Racing Posted March 10, 2011 Share Posted March 10, 2011 my car runs better without oxygen sensor plugged in. try that. my problem sounds similar. Quote Link to comment Share on other sites More sharing options...
Over30S130 Posted March 10, 2011 Author Share Posted March 10, 2011 my car runs better without oxygen sensor plugged in. try that. my problem sounds similar. It's worth a try and easy enough to do. If it runs better, would that mean my O2 sensor needs replacing rather than just run with it disconnected? I kinda want to get the best MPG when I can-nevermind, this is my Turbo car-hard to keep foot out of this one. Quote Link to comment Share on other sites More sharing options...
Over30S130 Posted April 29, 2011 Author Share Posted April 29, 2011 Update-hope this might help someone a little. Had previously fixed this issue by accident by just disconnecting the cables at the ECU and just plugging them back in. The problem has resurfaced again. Sputtering on initial take off even with light throttle. Releasing gas pedal and reapplying slowly seemed to get through this, but when trying to accelerate, when just starting to boost or at zero vacuum, power would hit a wall. When this last happened, I let off the gas and bumped the panel where the ECU is located with my foot and reapplied the gas and what do you know, all power is back. Problem not solved I know, but maybe I am atleast in the right location on this issue. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted April 30, 2011 Share Posted April 30, 2011 I got my harness and ECU from an '81 Turbo car I bought in San Diego and limped home to Phoenix... Must be kind of a common leak point - right above the ECU. My harness connectors and the pins of the ECU were badly oxidized. It took me a LONG time and multiple cleanings to get rid of the electrical problems caused by poor connections at the ECU. BTW - I did much the same thing, except I could reach the wires and connectors to my ECU. When my car would start running like crap, I'd reach down and wiggle the wires around until it straightened up... Finally got SO sick of doing it that I finally: 1 - pulled the ECU cleaned all of it's connector pins to a stupid degree 2 - pulled every wire OUT of each of the 3 connectors one-by-one a. cleaned and adjusted the connector on the end of the wire b. soldered the crimp connection between wire and metal connector I haven't had any problems since I did that... Quote Link to comment Share on other sites More sharing options...
Over30S130 Posted May 2, 2011 Author Share Posted May 2, 2011 Thanks for the info. May have to end up doing the same if the problems persistently reoccur, but doing OK at the moment. Quote Link to comment Share on other sites More sharing options...
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