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There are four wires to the distributor. Just check the red and black to see if it has power and ground. Signal back to the ECU (green and white) is a little trickier. Leave that until you've double checked your coil and igniter wiring. Make sure you have power to the coil and igniter at IGN ON.

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Well I think I found the culprit. I had a wire that needed to go to switched power hooked up to a black/white wire which actually wasn't switched power. That's what I get for making assumptions without my multimeter to check!

 

I have spark, but now I don't seem to be getting injection pulses. I ended up running around for most of the evening so I didn't even really get a chance to look into it yet. Hopefully the weather is decent tomorrow as well so I can look into it more.

 

Here's a bizarre note- I put my throttle linkage back together like it was with the old engine and my gas pedal sits on the floor and opens the throttle when you lift it up toward you. I flipped the linkage so the hook is upside down and that fixed it. Random things of interest.

Edited by Pac_Man

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So close, but so far. I have fuel pressure and my injectors are firing. I have spark. I have compression. The engine cranks and fires but just won't catch and start idling. I doubt it's because it is a fresh rebuild. My first suspicion is timing, but I don't really know where to start. I've been trying to research those who have had similar issues but have been unsuccessful in really finding anything useful.

 

I got it to barely run for a few seconds and I had to hold my foot down with the accelerator pedal to the floor or it would try to choke. It was very rough. I also noticed my tach isn't reading anything and I'm frankly stumped on that. Could the signal resistor be missing? I'm not sure where its physical location should actually be but I recall reading somewhere that it's inside the car on the passenger side so it should still be there. 

 

 

 

I also installed a stealthy killswitch for the fuel pump positive wire. Thinking about it now, I suppose posting the location on a public forum may not be the wisest choice. 

Edited by Pac_Man

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I'm going to guess no AFM signal.  It starts, sucks extra air, but the AFM isn't communicating with the computer so it leans out and dies.  Have you checked the AFM to computer wires with a meter?  Easy.

 

Attached a sample from 1982.  Can't remember what harness you have.

 

If you didn't connect the blue wire in the engine bay to coil negative you won't have tach.  That's how 1976 works.  You have a blended system now.

 

 

post-8864-0-64106500-1430527596_thumb.png

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I'm going to guess no AFM signal.  It starts, sucks extra air, but the AFM isn't communicating with the computer so it leans out and dies.  Have you checked the AFM to computer wires with a meter?  Easy.

 

Attached a sample from 1982.  Can't remember what harness you have.

 

If you didn't connect the blue wire in the engine bay to coil negative you won't have tach.  That's how 1976 works.  You have a blended system now.

 

Hi NewZed,

 

I attached what I believed was the proper blue wire but didn't notice anything when I was cranking the engine. I located another blue wire and didn't think it was the right one but tried it anyway. Still nothing. I'm a bit stumped at this point on that.

 

I'll go test the ECU connectors. If the AFM signal is not reaching the ECU, would the ECU also not send the signal to the fuel pump relay to power the fuel pump? Because I think I'm having that issue as well. I jumped the connection with a wire in the meantime but that's obviously not a permanent solution.

 

Oh and for reference, I have an 82/83 harness/distributor/engine.

Edited by Pac_Man

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Hi NewZed,

 

I attached what I believed was the proper blue wire but didn't notice anything when I was cranking the engine. I located another blue wire and didn't think it was the right one but tried it anyway. 

 

 

 If the AFM signal is not reaching the ECU, would the ECU also not send the signal to the fuel pump relay to power the fuel pump? 

You should test your wires before you connect them.  Make sure they're the ones you want and also make sure that they're not connected to something they shouldn't be.  For example, the blue wire branches off to the ignition module and Pin 1 of the old EFI harness.  Connecting random wires based on color is risky.

 

I think that the fuel pump relay is one of those things that can be done several different ways.  But if you didn't devise a new way to power the pump relay, then the pump won't get power because the 76 AFM had a switch that powered the relay.  Your 82 system doesn't have that.

 

A methodical approach, with a meter, to each issue is the best way to go.  You can burn up most of your work, or damage something, with one bad connection.  You'll end up using the meter anyway just to figure out what you damaged by not using the meter.  

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The way I have the fuel pump relay wired is the relay is activated by the signal from the ECU, similar to the stock 280zx setup except without the fuel pump modulator. Theoretically when the ECU sends voltage to the relay I should get voltage to the fuel pump.

 

I just measured resistance at the ECU and got ~200 Ohms from two different testers.

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So the immediate question is, is 200 approximately 240.  Might affect the way the engine runs but probably not your issue.

 

The bigger thing though is, you really need to take all of the measurements, or as many as you can.  The page number is at the top of the image I posted.  You'll probably find some problems and know more when your done.  Once you have the ECU connector and meter in your hands and the pages available, why not keep going?  Test everything you can with the meter, just to be sure.

 

http://www.nicoclub.com/FSM/280z/1982/1982%20280zx%20FSM/efec.pdf

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Did you remove or disconnect your stock electronic ignition module from under the dash?  The blue wire on the stock engine is the "signal to fire" to the coil, it also "tees" off under the dash, to the resistor, and then the Tach.  If you haven't already, you need to remove the blue wire from the stock module.  Then check your tach.  

 

Did you have the distributor spindle out of the engine and/or are you sure it's set properly?  Did you check your mechanical timing? Get the engine set to TDC on compression stroke, check position of the rotor.  make sure it's pointing to the cylinder one post on the cap.  You can undo the distributor adjustment bolt - take it all the way out.  turn the distributor whatever way it takes to get the engine running.  note it's position.  If it's outside the adjustment window, you need to reposition the distributor spindle properly.  When it's set correctly, the adjustment bolt will be almost dead center of the adjustment range with timing set at 20 degrees. There's a picture in the FSM of how the top of the spindle looks when properly installed, but lots of people seem to have trouble with that.

Edited by cgsheen

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Well just to see what happened I loosened the distributor bolts and rotated it. I moved it as far clockwise as I could and got the car to run a lot better. It dies immediately if I take my foot off the gas pedal, not sure if that's due to timing still being off or what. Here's what it's like now, but I only got a few minutes with it before having to leave again.

Also I disconnected the whole ignition control module and still no tach. :/

Edited by Pac_Man

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farnsworth%20good%20news.jpg

 

 

Since it was the easiest thing to test, I tried moving the distributor. Once I turned it as far as I could clockwise, the car would start and run if I kept my foot on the accelerator just a bit, but died as soon as I let off. Once I got the chance, I removed the bolts as cgsheen suggested and messed with it a bit more. This is the result:

 

 

 

Still no tachometer, though. No oil pressure gauge, either. I'm starting to wonder if I disconnected a ground somewhere or something.

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Life has been pretty crazy with school, taking 4 classes in one quarter is killer sometimes!

 

I ran into more issues, specifically the transmission mount and the driveshaft. I wanted to get the transmission mounted and bolted before finalizing my measurement for the driveshaft. Through my research I found a post saying that the T5 is 30mm longer than a normal L28 and Nissan transmission. I had a transmission crossmember from a 280zx with the curve in it. That curve places the transmission mount 15mm back, which left me with needing another 15mm. I had heard stuff like "I notched it" and "this guy used a differential mount" but the only thing that made sense to me was modifying the mount. I was recommended a fabrication guy who works out of his garage and does primarily old hot rod stuff. He cut the center part of the transmission crossmember and moved it back 15mm (0.59"). I took it home, spray painted it, installed it, and it fits!

 

So for anyone's future reference, the T5 sits back 30mm. The curved crossmember gives you 15mm, so just cut it and reweld it another 15mm back and you're golden. I forgot to take a picture out of the car so I snapped one of it installed:

 

IMG_20150529_163348_zpsqebbo6hn.jpg

 

Next up was the driveshaft. I'm not sure if I mentioned it earlier in the thread but I went with the route that was recommended to me of having one built. Others have used Powertrain Industries in California with good things to say so I went with them as well. For anyone interested in having one built by them, the part numbers used were:

 

Slip yoke: 1203-26S

Differential flange: 1202-39

 

This is a setup for the slip yoke of the Nissan/BW non world class T5 found in the 280zx turbo and the differential flange of my stock 280z r200.

 

IMG_20150529_144443_zpshti4s9pd.jpg

 

IMG_20150529_163334_zpsn8eijk7f.jpg

 

IMG_20150529_163326_zpsgppnq3ez.jpg

 

My measurement for the driveshaft from the face of the transmission output seal to the face of the differential pinion flange was 26 1/8". I make no guarantees on the accuracy of that measurement for your purposes. This is with the L28ET motor mounts if it makes a difference, though I've heard they're the same. After installing the driveshaft, I reinstalled the rear sway bar with the new end links.

 

Needless to say this was a big step toward having this car finally back on the road. I still have some kinks to work out. My gauges still aren't working and I'm not entirely sure why. I'm suspicious of my alternator not charging the battery even though I don't think the charge light comes on. I still can't figure out why my tach and oil/water gauge do not work, though I'm curious if the alternator has any effect on that. I also need to reclock the distributor/oil pump drive shaft. The ECU fuel pump wiring setup I have doesn't seem to work either. Worst case scenario I guess I'd just wire it hot since I already have a killswitch installed.

 

Once those issues are taken care of she will be ready to get back on the streets.

 

I think for breaking in the engine I'm going to run it for a while with just a screamer pipe where the wastegate would normally go to prevent building boost pressure. I know it will be loud but then I won't have to worry about building boost while breaking it in.

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I think for breaking in the engine I'm going to run it for a while with just a screamer pipe where the wastegate would normally go to prevent building boost pressure. I know it will be loud but then I won't have to worry about building boost while breaking it in.

 

Yea, don't do that...

 

You can just drive the car off boost if you are breaking in a rebuilt engine, you really shouldn't be romping on it anyway so that shouldn't be too hard. If you don't think you can control your self, just unhook the turbo cold side and put a filter on the charge pipe. The turbo will build boost and blow air out without it making it to the engine, and your engine will just breath in air through the charge pipe.

 

I would also make sure your gauges are up before playing with it too much, a local friend just seized his rebuilt motor from a lack of oil pressure.

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 The ECU fuel pump wiring setup I have doesn't seem to work either. Worst case scenario I guess I'd just wire it hot since I already have a killswitch installed.

 

 

After the first swap we did, we started just using the ZXT fuel pump relay.  It's actually a very simple circuit and then you just need to find the green wire to the fuel pump in the passenger footwell.  You simply tie the "output" of the fuel pump relay to the Green (fuel pump voltage) wire in that harness on the passenger floor that runs to the rear of the S30.

 

If you don't have the ZXT relay you can wire another standard relay in it's place.  The circuit diagram describes this very well and it's simple to do.  

 

As easy as this is, DON'T wire the fuel pump "hot" - let the ECU control the fuel pump like it's supposed to.  Much safer that way.

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I don't think so (at least not this easily), but I'd have to look at the circuit diagram for the Z32.  They introduced a "safety circuit" and re-designed the fuel pump circuit at some point.  With the Infiniti M30 ECU as an example, you have to rewire the entire circuit back to the fuel pump...

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Yea, don't do that...

 

You can just drive the car off boost if you are breaking in a rebuilt engine, you really shouldn't be romping on it anyway so that shouldn't be too hard. If you don't think you can control your self, just unhook the turbo cold side and put a filter on the charge pipe. The turbo will build boost and blow air out without it making it to the engine, and your engine will just breath in air through the charge pipe.

 

I would also make sure your gauges are up before playing with it too much, a local friend just seized his rebuilt motor from a lack of oil pressure.

 

What would the difference really be? With what I was thinking of, the turbo would not really see boost in the first place. With what you're suggesting, the turbo wouldn't build boost since the air would just be blowing out into the atmosphere instead of being compressed in the intake and cylinders. And I made sure I had oil pressure before starting the car.

 

It seems like there are two schools of thought for breaking in engines- treat it gently for a couple thousand miles or romp on it like you would normally. The most important thing seems to be using compression braking to push the rings out and seat them properly against the cylinders. This could be achieved without driving it hard but when I asked a tech (who has done these swaps plenty of times and is very familiar with Nissan's L series engines), he said get it on the road and put a load on it as soon as possible to break it in. This is what I had already planned on doing when I talked to him.

 

 

After the first swap we did, we started just using the ZXT fuel pump relay.  It's actually a very simple circuit and then you just need to find the green wire to the fuel pump in the passenger footwell.  You simply tie the "output" of the fuel pump relay to the Green (fuel pump voltage) wire in that harness on the passenger floor that runs to the rear of the S30.

 

If you don't have the ZXT relay you can wire another standard relay in it's place.  The circuit diagram describes this very well and it's simple to do.  

 

As easy as this is, DON'T wire the fuel pump "hot" - let the ECU control the fuel pump like it's supposed to.  Much safer that way.

 

I tried that as you were the one who informed me of it in a separate post I made regarding some wiring confusion. I'll double check my wiring but with that setup I wasn't getting voltage from the relay.

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"Tech" doesn't mean much these days.  No offense to any techs out there, but it's just the title that shops give to people that work there.  If you can turn a bolt without cross-threading you can probably get a "tech" title.  As opposed to a certification or degree in a technical field, like automotive mechanics.  Even a certification is only as valuable as the organization that gives it.

 

The factory probably knew what they were doing when they wrote their break-in procedure.  Page 27. http://www.xenons130.com/files/ownersmanuals/1982%20280zx%20ownersmanual.pdf

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Yup, titles are thrown around nowadays. I met a chemical engineer at the mall. She was the girl selling makeup. Makes me a bit upset as an actual chemistry major.

 

If you just run straight through the screamer pipe with no waste gate it will be loud as balls. That might not bother you, but don't really need to make a bad name for yourself you know?

 

If you let it run the normal path with a waste gate with the compressor to charge pipe coupler disconnected the turbo will still spool a bit and circulate oil, but you won't be putting boost through the engine.

 

Ideally you just leave everything hooked up and functioning and just drive it as instructed in the break in procedure. 

 

How rebuilt is your engine? I don't really see what you did to it in this thread.

 

There are certain myths regarding certain break in procedures, and some things are out dated. There are also very specific ways to break in new individual parts depending on what you are reusing etc. I think I generally followed the "how to rebuild" book along with several oil changes. I believe you drive normally and try to vary the RPM's. That doesn't mean throw it under max load all the way to red line and bounce it off the limiter, but it also doesn't mean to put around town at idle. 

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"Tech" doesn't mean much these days.  No offense to any techs out there, but it's just the title that shops give to people that work there.  If you can turn a bolt without cross-threading you can probably get a "tech" title.  As opposed to a certification or degree in a technical field, like automotive mechanics.  Even a certification is only as valuable as the organization that gives it.

 

The factory probably knew what they were doing when they wrote their break-in procedure.  Page 27. http://www.xenons130.com/files/ownersmanuals/1982%20280zx%20ownersmanual.pdf

 

Guess it was force of habit from my last job. Like I said, he has done these swaps plenty of times and is very familiar with the engines. He does swaps, tuning, all kinds of stuff. He's an older guy who has been doing this for years. Don't let my use of the word tech distract you from the other info, I wouldn't listen to him if I didn't know he knows what he's doing.

 

Yup, titles are thrown around nowadays. I met a chemical engineer at the mall. She was the girl selling makeup. Makes me a bit upset as an actual chemistry major.

 

If you just run straight through the screamer pipe with no waste gate it will be loud as balls. That might not bother you, but don't really need to make a bad name for yourself you know?

 

If you let it run the normal path with a waste gate with the compressor to charge pipe coupler disconnected the turbo will still spool a bit and circulate oil, but you won't be putting boost through the engine.

 

Ideally you just leave everything hooked up and functioning and just drive it as instructed in the break in procedure. 

 

How rebuilt is your engine? I don't really see what you did to it in this thread.

 

There are certain myths regarding certain break in procedures, and some things are out dated. There are also very specific ways to break in new individual parts depending on what you are reusing etc. I think I generally followed the "how to rebuild" book along with several oil changes. I believe you drive normally and try to vary the RPM's. That doesn't mean throw it under max load all the way to red line and bounce it off the limiter, but it also doesn't mean to put around town at idle. 

 

Crank was shaved down .010" and bearings were appropriately replaced. Cylinders were honed and new pistons and rings were installed. Everything else was checked and of course gaskets and such were replaced. I suppose "romp on it" was more aggressive wording than I was going for.

 

And putting a filter on the charge pipe would be difficult as I'm using the stock J pipe... I'd have to think about that one.

Edited by Pac_Man

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So a fairly comprehensive rebuild.

 

I would say just plumb everything up and run the waste gate as designed and just stay off boost. You won't build much pressure even at high rpm unless you really give it a lot of throttle quickly.

 

Broken in well you will have plenty of time to enjoy it. Seems like you have a few things to check off before hand though.

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Since you've already started it and run it for a while it may be too late, but I would focus on the cam shaft and rocker arms, if they're new.  That seems to be the most common problem people have with rebuilt L6's.

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