69sroadster

A lot has happened since this initial problem. I'm not sure what started the mess but I'm guessing it was a combination of the starter solenoid and the alternator diodes going out. The alternator was grounding out through the case. It must have also been putting out some bad/dirty power since a lot of other components have been shorted out. In the end I've had to systematically pull every single relay, switch, motor, light off the harness and test for improper grounding. I've learned my JDM version S130 has a few differences from the USDM versions and repair manual...things not on the wiring diagram or different color schemes etc. That has made it a bit more challenging. So far here is what I've found also bad: horns, intermittent wiper controller, under seat belt chime, some random green relay under the seat labeled "switching unit" that nobody has in Australian/Canadian/American models. I also found the rear defogger timer (not in USDM manual) when connected pulls a short to the fuse block but it's not the timer rather something that is fed by it. I can't find out what else it's connected to from under the seat and going to the back besides the grid which is fine. I'm slowly putting it all back together one item at a time to make sure no other new shorts come back on the harnesses. I also found that ALL of the pedal switch grommets are gone and were leaving the plunger switches open for the brakes/clutch. I fixed those with some simple pennies and glue LOL. The battery seemed like it didn't have one electron left when I hit it with the voltmeter so I will likely have to get a new one of those after the abuse it saw. It's all slowly coming back together. Anyone have an intermittent wiper controller/timer they can sell me? Thanks for reading and hopefully I can help some others in the future when they get electrical trouble. It's a long tedious process but can be figured out. Oh and does anyone have a schematic for the wiring on the rear defogger timer?

I'm now on Oahu and found that my intermittent controller box/relay has shorted out internally. Does anyone have one they're willing to part with? Ebay came up empty and the junkyards here aren't really good for ZX's. I also need this to pass the safety inspections here. Thanks for the help, Sam Kraemer Mililani HI 96789

I know this is going to appeal to a smaller group of people and experts, but I figured I'd give it a shot. Please help if you can or know someone that can pass their contact info along if they're okay with that. I have a 1979 JDM 280zx that developed some painful electrical gremlins a few months ago. I'm not sure which came first, but I do know so far that my starter solenoid was hanging up and the SR20 alternator diode(s) shorted out through its case (not necessarily in that order). The car started and drove, but lights/accessories would randomly cut on/off and the voltage gauge would drop to around 9 volts. I started a long journey of using the wiring diagram, a voltmeter and a lot of trial and error to discover a few other shorts. One was the license plate light, one of the horn green power wires, and the ASCD controller box. Everything else so far checks out good but I did find something strange...or a few strange somethings. Under the driver seat are a few extra relays/boxes not in the FSM. One has a stamped label that says "Switching Module" and the harness going to it (stock by the looks of the main harness wrap) and it has a White with Red stripe wire that is shorting out. I've checked every other wire of this color and they are all good. I have no clue what this thing is and does besides that label. Does anyone have a JDM 280zx wiring diagram, or know what this thing is? The rest of the wires on that connector do not offer any clues either. The best I can tell the wires meander forward to the main harness area. There also seems to be an extra relay along the bottom door frame rail in addition to the diode box. I'll be chasing down this short, and I think one other that was on a few yellow/green wires. The offending list is getting shorter as I continue to remove ALL components and relays one by one. I've got almost everything disconnected now. I'll see if I can snap some pictures later to help out. Mahalo, Sam Kraemer Mililani HI

Aw man has this been frustrating. So I disconnected the alternator and shot a short test against the two output posts and they both showed some grounding to the casing. I also shot the wires themselves after disconnecting them and the blue wire going to the loom was showing a short. Digging deeper I found a short in the yellow feed wire to the starter. I disconnected it and it showed a short on the little wire going to the starter solenoid, so I guess that's bad too now. I tested the fusible link box for a short and it initially had one until I disconnected the alternator. I went inside the car and pulled the fuse block off the sidewall to shoot wires too. Most of those are showing a short somewhere. I disconnected the ignition/accessory relay harness and three of those wires are shorted somewhere (WB, WL and BW). I think I need to re-test those after the sequence of disconnecting other components. The fat white wire going to the blower across the fuse was showing a short/ground. One of the blue wires from the EFI relay was showing a short. This is going to be a real pain! It's like there are shorts everywhere and I find that hard to believe. Maybe more likely that some one interconnected component is affecting a lot of feeds, but I can't seem to figure out how/where. So frustrating. Oh yeah, the main battery cable is fine with no shorts. I'm tempted to just replace the starter solenoid and alternator, hook it all back up and see what that shows without running the car yet. In the back of my mind I'm thinking that somehow a relay is stuck closed. The car was running fine but was turning over a bit slowly the last few times before this all shook down. The battery was showing a good 12v before turning it over. Once it started it was showing 14v on the dash meter. Everything was working just fine. There was one or two times the voltage before starting acted weird. I have to think back about what it was doing with the voltage, gauges, lights etc. Almost like it was not all there until it was fired up and then it seemed to be okay. I'm taking a break for now since I seem to be making less progress other than the solenoid and alternator shorts. Time to sleep.

I'm working through some weird electrical issue now that I've never had before. I hate those. I was in the middle of working out the suspension for the Hawaii inspections. I added the full Techno Toy Tuning adjustable front struts with their bump steer spacers, 250lb springs, and adjustable tension rods. That took about a whole day to do including replacement of the front bearings, races and seals. I noticed that my Rota 17x9 rims up front and tires come really close to the strut bottom spring perch. So far I'm going to limit how low I put the car with this very near interference. A spacer should take care of that later, but I really try to avoid those. I added some cheap rear spring spacers to lift the rear a little from the Tokico Blue HP set. My hope is that this will temporarily increase the rear camber to within factory specs and remove a little toe back there, so that I pass their silly rear alignment here and can get registered. Afterwards I'll take the spacers out and eventually get eccentric adjusters for the toe back there. So far the car rides really well. There were a lot of fixes in the last two weeks though. I added a flex section to the exhaust to reduce fatigue on the SS down pipe. I added a hanger to the exhaust near the transmission mount (custom 350z 6 speed mount). The front bearings have a very small amount of play/wear but now are new. I'm pretty happy so far with the TTT stuff and how it feels. After an alignment I should be better able to state how it handles, but I have to get rid of some stupid short first. It was running pretty good for having electrical gremlins before I parked it.

So I thought my car was acting a little funny the last few days of driving, but it wasn't until today that it seemed to be really noticeable. The battery turning the motor over seemed like it was getting low on juice and only turning it over slowly. Once it fired up it was fine. I thought that was weird until when I shut it down. It seemed like the voltage gauge went down initially, then bounced for a bit and then went back up to 12v. I thought that was weird and that it was supposed to normally go back to the zero mark with the keys out and completely locked steering. So I put the keys back in and turned the ignition switch a few times from locked/off to run. It seemed like it was staying on when it should be off. I had to run into work so I left it alone. At the end of the day I came back and noticed the same thing basically. I drove all the way back home and parked it. Once there I started checking around for the usual suspects. Battery cables are good. No obvious ground on any big wires under the hood area. Voltmeter on the battery showed a good 12v. I pulled the fusible link cover off to inspect and I notice that the "B" labeled one going to the ACC/IGN (closest to the engine under the cover) was charred and barely touching the post. Hmm...it looks like it was trying to protect against something but what? I started the car (barely) with it off the post. Everything seemed to work fine too. I temporarily connect it back and yep, it's getting pretty hot. I can tell its loading down the alternator and pushing a lot of current through there. Oddly, I also see that my voltage in the car is reading 14.5 v with this fusible link disconnected. Is there another way for that voltage to get to the gauge without the fusible link connected? I'll have to really scour the wiring diagram to find out. It got dark before I could really tear into this, so I'll have to do some more digging. I don't suspect the alternator since it's giving a good 14.5v at least to the gauge. Is this a bad assumption? I want to figure out what could be shorting that would act so weird like this, but still let the car run or even start. The only other clue I seem to have is a quiet but high pitched tone near the radio area that I don't recall being there before. Everything in that area seems to work for now and I didn't do any work there. I'm going to have to start from the basics with my voltmeter shooting for continuity/grounds starting at the alternator and working to the starter and ignition. I hate that this had to happen this week with my alignment scheduled for tomorrow that is holding up my new registration here. Maybe after this is all straightened out I can get back to the suspension write-up for going to the TTT front.

Did your ZX start drawing a lot of heat through the fusible link too? Mine is just starting to act somewhat similar.

I found a place in Australia again thanks to some other posts I found here and other places to get some better quality eccentric bolt rear toe adjusters. Well at least they looked pretty good online. K-Mac. They seemed to offer quite a wide range of similar parts for many cars. They should be delivered within a week or so. For now I'm going to keep burning down the full 21 gal gas tank in the ZX and look for some of those cheap coil spring inserts to bring the ride height back up temporarily to get the rear alignment checked and hopefully just back within the limits of the factory spec. This should get me through the Hawaii inspections for the time being and registered while I wait for the rear kit to come. I'm interested to see how much the temp "fixes" will change the static rear alignment.

I'm also interested in this bracket mod

Where is Pontiac kids arm mods posted?

I forgot to add that this recon alignment check is a one time deal...unless I make it extreme later on and a police man calls me out on it, which I don't plan on doing.

So I found myself in an interesting dilemma. I had to move to Hawaii for a job. I brought my 280zx with me and to get it to pass their recon and safety checks, I have to get an alignment that shows the car is within factory alignment spec's. I just had the Firestone inform me that the front is out but I will taking care of that with a TTT camber kit and adjustable tension control rod. The front was -1.5 camber, 4.4 caster, and 0.01 toe on the left.... and -1.0 camber, 3.8 caster, and 0.20 toe on the right. The front has all new urethane bushings as of three years ago (except for the tension control rod front/outer which is rubber). I stacked the TC rods with a urethane on the inside/back. The rears were sitting at -2.1 and -1.8 camber and -0.22 left toe and -0.14 right toe. From what I know there are really not any adjustable options for the rear on the ZX. However I was wondering if I didn't have the full tank of gas would it have been better off. I'm only about 1 degree too much negative camber on the rear. I may also temporarily add some of those coil spring spacers in the back to help, although I don't like them. I'm not sure what I can do about the toe. I did have all of the rear bushings replaced about three years ago with urethane. Any recommendations? Right now it's sitting on Tokico Blues with their springs at all four corners.

After my latest track day at AMP, I have to revise now. Running VR 20w50 oil in 80's temp I was seeing around 95 c normal driving and about 115c on the track with about 10-20 minutes of all out racing. The coolant temp this time was a surprise to me. It was normally not much higher than usual sitting around 70c but there was a time when it went up closer to 100c. I thought what the...why not try turning on the fan despite the speeds and see what happens. It dropped the temp down very quickly again to 70c. I didn't expect that given the speeds around the AMP track anyways. Now that I think about it the coolant temp may have spiked this particular time when I blew off some of my vacuum lines. Too bad the Go Pro didn't actually take video to watch and learn from.

Now that I read over your thread and are spending some $$. If you end up going with EFR and full race you might as well get their twin scroll manifold T4 style and get the newer/bigger mixed flow EFR turbo in the same twin scroll setup. They've got dynos showing it still does better in response than a 2871r yet makes so much more overall. You may find yourself with some clutch slipping and transmission issues depending on driving style and actual results with power. Personally, I think I got just as much fun factor of a turbo upgrade by moving to the 350z 6 speed instead of the stock 5 speed SR transmission. It was a bit of a pain though I admit doing the swap.

I purchased a new generic Chevy aluminum radiator from JEGS for around $180. It should just fit inside the frame rails if you get the right one sized out with a basic measurement. I also bought the Jags That Run mount kit but you could easily fab something up yourself. I think I may have had to adapt the lower radiator hose size too. I also found a Lincoln Mk8 or Thunderbird electric fan and it fits almost perfect against the radiator and also comes built into a fan shroud. It must be the biggest factory electric fan ever near 18" diameter. I only ever run it on low speed through a relay and that's all I've ever needed in my ZX. Maybe the ducting is different for a Z body though now that I think about it. Now that could also affect the radiator and fan selection too. Oh well, my bad. Well it worked well for me at least. That fan is a bit deep so it may still work. I had to trim the shroud just a little to fit even more snug against the radiator. All told it should be near what you were aiming price wise.