xtreme 2 Posted March 11, 2007 Share Posted March 11, 2007 Hey guys. Haven't posted here much but the guys at ZDriver are becoming retarded in trying to help me with my problem, so I am posting it here hoping that someone can help. I started the Z31 ECU Upgrade to my 1982 280zxt back before Christmas, but with snow and a lack of a garage I was unable to complete it until this past weekend when it started warming back up. I double checked all of the steps from the tutorial, switched the 108 wire so it would control the Fuel Pump, added the 84 disk to my disty, and have an 84 Turbo ECU and MAF. The car ran perfectly fine before the swap, but now it is acting weird. If I go out in the morning it will fire up fine, idle fine, and revv with no problems. But then, after a bit, it will just stutter and die. Sometimes it will start back up no problem, but sometimes it will not want to start back up for the rest of the day. I double-checked the wiring and everything is correct and secure. Today, my friend came over and we went to work, adding a fuel stabilizer thinking the gas was just impure and when under a load was fouling up the plugs. It fired up easily after dying, but then died the same after about 5 minutes, and won't start back up. I have another project car that we took the adjustable Fuel Pressure Regulator off of, and put it on thinking there was too much fuel and it was blocking the spark. No difference. I then pulled off the fuel lines we had just installed and found that they were all still dry, both sides of the FPR, showing that there was no fuel entering the system. We are both out of ideas, so I am looking for help. Like I said, if it sits for a while it will fire right up, but then dies within minutes of fuel deprivation. Also, after we installed the aftermarket FPR to be able to tune the Fuel Pressure, when we went to start up we heard two pops, one from the intake filter and one from the wastegate, both put up a little cloud of smoke. Any suggestions will be gladly taken into consideration. Just need it running... Quote Link to comment Share on other sites More sharing options...
GrayZee Posted March 11, 2007 Share Posted March 11, 2007 I would start by bypassing the fuel pump relay completely. Basically, unplug the FPR and stick a jumper wire between the two connections that that complete the high current side. Doing this should cause the fuel pump to run all the time regardless if the engine is running or not. If it runs good, and continues to run good, I would suspect a screwy FPR or the signal wire from the ecu. Quote Link to comment Share on other sites More sharing options...
xtreme 2 Posted March 11, 2007 Author Share Posted March 11, 2007 how do I tell the high current side from the others? and which Relay do I bypass, since there are 3 of them? Quote Link to comment Share on other sites More sharing options...
GrayZee Posted March 11, 2007 Share Posted March 11, 2007 I only know of two relays that are directly related to the engine control system. (efi and fuel pump relays) If you wired up the swap yourself I would assume you already know where the fuel pump relay is, as it needs a 12volt + source added to it to run this swap. Are you still using the stock fuel pump relay, or did you add a different one? For my car I never used the stock one because it is in a nasty spot and I don't like crawling around under the dash. Plus I had already added my own 12 guage wires to the fuel pump itself Quote Link to comment Share on other sites More sharing options...
xtreme 2 Posted March 11, 2007 Author Share Posted March 11, 2007 no still using the stock one. The dash is currently out of the car being fiberglassed so I just stuck with that. I am basically just following this write-up here: http://probe-enthusiast.com/280zx/Z31_swap.doc If it's not listed there, I didn't do it, so that could be part of the problem. Can you offer anything beyond that to help me finish this? Quote Link to comment Share on other sites More sharing options...
GrayZee Posted March 11, 2007 Share Posted March 11, 2007 Well I am not really familiar with the stock FPR, I don't even know exactly what it looks like or what kind of plug it has. All I can tell you is that the fuel pump relay needs four wires: signal or "trigger" that goes to the ecu (-) 12 volt (+) source to complete the coil trigger (ideally switched to ignition, but straight battery power will also work) The way it is described in that site about using the black/white wire will work, but that comes from the efi relay (another source of possible error) The above two form the "low current side" The two below are the "high current side" 12volt + straight to battery (with a fuse in between) Output to the fuel pump (+) Quote Link to comment Share on other sites More sharing options...
xtreme 2 Posted March 11, 2007 Author Share Posted March 11, 2007 ok thanks... I'll look into that and then see where I am at in the morning... Quote Link to comment Share on other sites More sharing options...
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