New World Datsuns...

UPDATE: FUCK THAT SHIT, I'M KEEPING HER AND MAKING HER RUN!!

Alright, have just about everything wired up right now. Have to wire the magnetic trigger, which is already run, so two spades and done, minus getting some wire loom. Then have to run a new vacuum line to the Motec ECU. Last bit is I need to make a 1/8 pipe tap so I can screw in the air temperature sensor. Thinking I'll remove the air bleed fitting right behind the throttle plate and make a little adapter out of aluminum. Should be easy enough.

The only thing I am wondering now is if the Motec is going to have any issues with the Fast E6 multiple spark discharge. It has a wire for coil negative, as does the Motec. Curious if that's going to affect it running being it can spark up to 3 times or whatnot per ignition event. I sure hope not, but we'll see. I think there may be a way around it if it does, but I'm going to cross my fingers and hope for some luck.

Ok, car is all wired up. Tried to start, no go. The Hi6R Multispark FAST box is getting power and trigger signal, the red LED blinks fast while cranking as it should. The ECU has power, but as soon as I hit the starter switch, it shows nothing. Pretty sure main power for that is coming into the fuse box, as all the other switches stay lit, and it doesn't have a regular ignition switch, just a couple fuse boxes and switches, etc. Standard race car stuff.

When the ECU is first powered on, it reads "25" in the box, and the red led is at 500 rpm. After trying to start it, it comes back on, but waits about 10 seconds and it goes to 1000 rpm at the red led and reads "15" in the box. Not quite sure what that means. I'm going to send an email to Motec to see if they know.

Furthermore, I'm worried about the multispark box causing issues with the Motec. Mainly because as per the instructions of the Hi6R box, it specifically mentions only the orange and black leads from the box should be going to the coil, no other wires.

The Motec only has 12v battery, 12v switched, an air temp sensor, water temp sensor, and coil negative. That leads me to think it's figuring out how to operate with the ignition signal. If it has a multiple spark event the coil is firing multiple times. Which means the ECU won't know what to do.

I have thought of a work around that I think will work. If I connect the coil negative wire for the Motec instead to the magnetic trigger negative wire, then it can only see the one spark event, and it should work the same I think, it's a path to ground as the signal. In which case the ECU will have the proper information to fire. Any thoughts?

Would the car run without the Hi6R box or is that essentially the ignition module in your system?
My brother's Z had one of those (back when it was Crane) but I honestly don't remember much about the system. Car came with it.

It would, but on the original system. Wrote Motec, had a very nice guy email me back. He suggested trying the tach spout off the Hi6R as the negative coil wire, may work that way. I haven't had a chance to try it yet, but I'm hopeful that may be all it needs.

So here's the odd part. I have a red status led, the instructions only allude to 1. It's one with power, blinking during crank. Tach is now working, cranking at 3-400 rpm or so. But as I crank, the ecu shuts off after a half second or so of cranking. Switching on and off turns it back on. With or without the ecu on during cranking, there is no spark. I got zero. On the instructions, they say if I have solid power, then blinking power during cranking, the ONLY other option is trying a different coil. I didn't think it was bad, but figured, hey, I'll check it out. Got an MSD Blaster coil and yeah, no change, no crank.

Now I'm thinking about wiring it through the GM module. You use the white wire then, not the green/violet wires for the magnetic trigger. I still have the GM module mounted on that distributor. Can't figure out what's going on. Theoretically it's all hooked up correctly. I can smell fuel when cranking before the ECU shuts off. I've still yet to figure out if that's all or only part of the problem.

The guy at Motec said I might need a pull up resistor in the tach feed to the Motec in the 1000-2200 ohm range. Think he meant kilaohm? Anyway, shit still isn't working. Anyone else have any bright ideas?

https://static.summitracing.com/global/ ... 0-6400.pdf

Figure 8 on page 11 is how I have it hooked up now. The only difference is not a square coil, which shouldn't make any difference. Also, these instructions are not the same as what came in the box. Mine do not reference different color status LEDs, they say only one, and don't identify the color.

Ok, wired through the GM ignition module, used white trigger wire this time. Good news, I have spark! Bad news, ECU still shuts off very shortly after cranking. Has to be turned on and then off again to operate. I disconnected the signal wire from the ECU coil signal and cranked, ECU doesn't shut off, so it's not a backfeed issue with the starter or something.

I've tried two ways to connect the signal wire. The first was through the tach output off the E6. The second was to connect into the white trigger wire as it ties in to what would have been the negative coil wire, though it's interrupted and sent to the E6 box, then separate wires run out to the coil.

I'll re-check my switch settings on the ECU, and the harness. It's possible I have something routed incorrectly, but at the moment, the signal is what appears to irritate it.

Keep picking away at it, eventually your going to get it working properly.
This is why I cannot deal with modern engines, if I could I would have already installed a VG30 in the work truck.

So I had a brilliant idea this weekend that I had crossed the grounds for the injectors and ECU. I though, yeah, that's the ticket! And tonight I proceeded to recheck all my connections. Not a darn one was out of place. I did find that as soon as I hit crank, the ECU shut off and the fuel pump relay kicked off. So I'm thinking it's still a signal issue.

My next plan is to disconnect the FAST box entirely and attempt to run it just like the original system was. Again, all I wanted the FAST box for was a rev limiter and boost retard, which would be quite nice. But if it won't play nice with the ECU, there's not much I can do about that. Either way, I'll bypass it all this weekend and leave it in place. That way if it does the same thing with the original coil and ignitor unit, I'll know it's a problem of the ECU.

And annoyingly, there is a potential I fried something when I attempted to start it with the negative coil wire hooked to the Motec and the FAST system. In which case I'll yank the thing apart and try and figure out what went wrong and have someone else fix it who's better at circuit boards. At this point I'm guessing it's going to work with the original system, though I'm not sure how or why. The Motec guy mentioned a pull up resistor, I'm going to google those now, because I haven't the foggiest idea what that is.

And I find it funny this is a "modern" engine Wayno. Lol. I'm not sure a 1983 engine with a 1989 ECU would be considered modern.

Modern must be relative.

Fingers crossed you get some answers.

Damn!! Figured out I probably hurt the Motec while having it still attached to the coil with the FAST Hi6R running. Have my electronics genius buddy attempting to fix the Motec now. Figure I probably burned a chip. Good news is those old school chips are cheap. If it can't be repaired, then it's new ecu time. Fortunately, the same fellow sells one for much less than the big names! Either way, the car will run!

Glad you finally figured it out. Not great news but sounds like a relatively easy fix.

Theoretically it should be. My wiring guy has it on the bench for tonight, hopefully I'll know something tomorrow and it will be fixable.

IT RUNS!!

So here's what was going on. Gave it to my electrical guy, he couldn't find anything wrong with the ecu. We decided we had better do a testing session in the garage yesterday to see what was going on. After verifying my wiring was correct (unlike the wagon), Chris found we had no signal to the injectors, which was odd. I had verified there was 12v there at some point, but it certainly wasn't at that time. After figuring that out, he directly shorted the injectors so they got full open via the board, we could hear click clicks in the engine bay, a good sign. Then we disconnected the MAP sensor so it could get full fuel pulse (fooling the ECU into thinking it was WOT) and hit the key. Cranking cranking, and Chris started turning the screws up, and vroom!

It starts hard for first crank, probably too much fuel and I don't even know what the timing is set at right now, but short of it is, it runs and idles and is repeatable. Yay! We figure either the injectors got partially stuck since it had been sitting for a few years, or being the pots were turned down too far, it just wasn't enough pulse to open and get fuel to start.

The other thing to note with the Motec Screwdriver ecu is, when you start it up, it will go through it's self-test sequence and the 100 rpm, 200 rpm and etc lights will light up and display a value. Starts with lowest and changes up to next rpm band every 15 seconds. BUT, when you're cranking the engine, when the ecu is running, NO LIGHTS WILL BE DISPLAYED!! I thought I was going to have a wizzing red led band that followed the rpm curve, but no, it's just blanks. This is why when I thought it was getting trigger it was shutting off, in actuality, it was doing what it was supposed to do, and the fuel pump relay turning off, was actually turning on because it was seeing trigger pulse. It just wasn't getting any fuel to start.

So there you have it. Had I known how the ecu worked, I could have figured this out probably, but I didn't, and after banging my head so many times, I figured someone else checking it out was a good idea. Sometimes you have to step away from the problem and have a second set of eyes on it.

Also, I do NOT have the FAST Hi6R box connected currently. I'm going to sell that to someone who can use it as the car runs fine without it. And, as pointed out by a few people, if I miss a shift at autocross, fuel cuts and ignition cuts can't do anything for a mechanical overrev, so really, don't need it. Just need to put the other transmission in which is infinitely better and should be less misshifts. I even entertained sticking the slushbox in from the wagon, but I don't think I'm going to do that. Might break it.

Now I have a huge list of crap to start addressing on the car from brakes to radiator to air cleaner, transmission, but I know she runs. Huge victory!

Two big thanks:

1. Chris Cashion of https://speedyefi.com/ for testing the ecu and figuring out the issue.

2. Simon Wagner from Motec http://www.motecusa.com/, who entertained my trouble-shooting antics and gave me more than the time of day in a number of emails and was very helpful. I apologize it was ultimately my error, not the ecu. And now we know hooking up a FAST Hi6R box won't kill it!

Yay progress!

Alright, finally got the wiring all sorted out. It's all permanent, though for some reason the alternator isn't charging now, need to figure out why that is. Possible it just died, but somehow I think it's related to something I did. Has power going in and power to the field. Need to re-check with a volt meter. Anyway, everything works. Ran a brake line across the firewall for a vacuum connector so I only have two short sections of soft vacuum line to the Motec.

Double checked the distributor for clearance, there is ample clearance so I'm not worried about the drive gear anymore. That's nice.

Found (oh lucky me!) a new reman 200sx brake master cylinder tucked away in my drawer of un-used parts in the garage, which is good, since mine is leaking out the back. Plus now I don't have to buy anything new.

Mounted the factory airbox again, minus the flapper box, have a 80 mm tube coming and connector, should be able to make it work. Have a factory KN filter in there from previous which will be plenty good enough.

The radiator is leaking, and Todd thinks he gave me the other spare radiator, so I think I might have put it in, and I think it might be leaking. Going to check around the garage for another, have to figure that out.

Removed all the factory wiring harness for the 280zx turbo, and ecu. We'll see if I can get a plugged nickel selling those or they'll just end up in the rest of the old parts pile.

Need to re-assemble my transmission downstairs and put that in the car. I'll probably get it ready to go and install it later when the weather is nicer and I can do it outside and jack it way up with lots of space.

Also need to remove a shit ton of vacuum junk on the intake manifold. Same with the small intake water pipes as they're not used now with the Motec. That reminds me of the temp gauge which goes up almost with rpm when you're on it, indicating 220+, but then as soon as you let off, it settles right back down at 180. Never seen a temp gauge do that, and it's in the thermostat housing. Actually, I wonder if the sending unit is hitting the aluminum? Anyway, need to put that somewhere else and probably wire in a better temp gauge. I ran it at autocross and all the way back without any overheating issues the last time it ran and it was still doing that.

Although now that I'm thinking of it, I suppose that could be a head gasket superheating the water. But if that was the case it wouldn't cool back down on extended running. Ok, just freaked myself out, I'm better now, just a gauge problem.

Still have quite a list to do, but things are coming along nicely.

Got a little done this weekend. Took way too long to make the air filter housing and piping fit, but it's complete. I'd like it a little different, but it should be ok. I'll have to do some testing and make sure there's enough give so the boot doesn't rip. Also got the new (refurb) 200sx brake master cylinder installed, had to make a custom rod. For some reason, the factory master had a rod built into it. Freakin' weird. Never seen that before. Still need to bleed the brakes and flush all the lines. Got some Wilwood 570 fluid that ought to work quite nice according to my racing gurus.

Chucked up the bolt for the brake rod in my drill, made a lathe with some steady action at the grinder, then some 600 grit to smooth it up.

Alright, so after much cussing and managing to dump a jar of dirty brake fluid over, and in my left eye, and subsequent rinsing for 10 minutes, and then almost tipping it over again, I finally managed to bleed/flush the brake system with new Wilwood 570 fluid. I have the z car barely off the ground enough where I can go under it on the creeper, scraping my belly against the exhaust. Either way, I now have a firm pedal and can move on to other items. The list is dwindling! I'm going to eat lunch now before I throw a wrench through something. The giant mess is now covered in cat litter, but it's the passenger side I can't get to anyway, so basically it's going to sit there until I can back the car out, but that will have to be nicer weather since I don't have any other covered space for it. Need to finish the wagon and put it on the larger side of the garage. That would be ideal, but since the wagon is there now, I'm stuck on the dinky side that barely fits a 13' long car. Better than being outside though!

Ok, got a bit more done today. Swapped out the radiator. Found the other z car radiator I had looked near identical, but the mounting fins were 1" off. So I ended up tracing it out on some cardboard and made a pattern and then drilled three new holes. The bottom right worked out exactly. That was weird. I'm guessing it must have been out of a different Datsun, though I'm not sure what. Had the same tilt to the cap. Anyway, it's in and seems to be holding pressure so that's good.

Then I started tuning and ended up on the richest setting of the MoTec, which didn't seem right. Kept getting 17:1 or worse idle ratios, but it was clearly too rich, especially when hitting the throttle.

Idle is too high, at 1100 or 1400 depending. Think I'm going to adjust the throttle stop screw since it does have a lot less restriction not having the flapper box in there. Sprayed all around looking for a vacuum leak, amazingly didn't find any. (Lots of vacuum lines I haven't removed yet.)

On the tuning, I did find a very large problem suggested by my Datsun guru. He asked where my o2 sensor was, and I told him I put the wideband in the stock location. The stock location is literally two inches past the turbo. I was told that was too close. So looked up the instructions (which I read, but not good enough the first time) and guess what? Twenty four inches past the turbo is ideal. So that will probably fix up the wideband so I can get accurate readings. Just need to weld a bung on the pipe further down.

Didn't get my plexiglas rear window in, but did yank the wheels and check the suspension for adjustment. I'm going to have to do something there. It definitely needs to be higher for driving on the street to autocross. It whacks everything currently and scrapes gravel.

So next installment, new o2 bung. Also need to check fuel pressure and fuel pressure regulator since it's still using the stock regulator. And really I should probably do new fuel injectors and probably a new set of plugs since I've been running it pig rich again apparently.

Good news is besides the transmission and some tuning, she's pretty much ready to go!

Progress is always good, it's them steps backwards that test us.