L28ET swap, no spark!

[240ADAM]

So I swaped a L28ET into my S30, wired it up just as all the write ups say to and I have no spark. The ECU has power while cranking, the ignitor has power and so does the coil. The one thing that is not happening is I pulled the distributor out with power on and spin it, shouldn't the injectors click? well there not. I even swithced out the CAS and still nothing. Also will the ignitor pass power on to the coil if it is bad? Cause it looks pretty corroded! Any Ideas? Bleach? Skib?

[Icehouse]

Yes the injectors should be going. Did you ground ALL the ECU grounds? Did you make sure to hook up the all time power to the ECU? That wire also powers the injectors (constantly, even when the key is off.) I was under Franks car yesterday and forgot to call back. Pull that CV for me and I'll fix it :D

 

What year is the Z31 harness from? I have a few z31 FSM's on my computer, need to know which one to print out.

[240ADAM]

Ill pull it tonight! When you coming over? What side axle you need? I need to get that thing going so I can work out any other bugs and drive it to canby!

[Bleach]

Which writeup did you go by?

 

Injectors are a single bank, all fire at once if that helps.

 

The 'ignitor' little black box by the coil tells the ECU that the distributor is firing and then the ECU detects the CAS at the dizzy. That piece by the coil is key and has to plug into a certain spot on the ECU

(not sure if ignitor is the proper term though. I hope we're thinking of the same piece)

[240ADAM]

Which writeup did you go by?

 

Injectors are a single bank, all fire at once if that helps.

 

The 'ignitor' little black box by the coil tells the ECU that the distributor is firing and then the ECU detects the CAS at the dizzy. That piece by the coil is key and has to plug into a certain spot on the ECU

(not sure if ignitor is the proper term though. I hope we're thinking of the same piece)

 

I used the one on HybridZ that the brezcar guy wrote, yeah we are talking about the same part. Is there any way to test it? I hooked it up right its going from the t plug on the ignition module or ignitor what ever it is into the harness near the ecu and the other black and white wire is switched power. If the ignition module is bad will the injectors fire while spinning the distributor?

[Bleach]

If the ignition module is bad will the injectors fire while spinning the distributor?

I could test that by unplugging mine and turning the distributor I think.

 

I'll see what I can do. I'm packing for a camping trip tonight.

[Icehouse]

Wouldn't the injectors still pulse without the ignition module? Seems to me that the ignition module takes the load off the ECU.

 

O yeah I need the short axle that's it.

 

 

Did you find out what year the harness is? Hopefully tomorrow, Frank is having a BBQ for his B-day, your coming right?

[240ADAM]

Yeah I'm going to Franks, I'll get that axle off tonight.

[yellowdatsun]

I'm assuming that by talking about spinning the dizzy, you are using an 82-83 engine, correct? 81 had a crank mount CAS.

 

I will tell you that these engines run infinitely better using the Z31 300ZX ECU and MAF. For whatever reason the 280ZX stuff is VERY finicky, and will give you all kinds of problems for the smallest things. The Z31 stuff can run with whole things totally disconnected, and still be just fine. My 81' 280ZX turbo has the Z31 stuff, and runs SOOOO much better than either it did originally, or my other 280ZXT's ever did.

[Icehouse]

I talked to Curly today, he has the early z31 turbo EFI, for some reason from what I gather he isn't getting injector pulse or spark. Me and Frank are going to head over tomorrow and see what we can do.

[yellowdatsun]

Ahh, so he already has the Z31 ecu swap. If that's the case I'd bet it is one of the swapped wires not being connected properly. There's only like 5 wires that need to be spliced into the car's main harness, but if one is wrong it won't fire.

 

I have swapped 81' 200SX EFI into a 71' 510 w/L-18,

 

Later swapped 85' VG30 EFI into the same 71' 510,

 

and have also swapped the Z31 setup into my 280ZXT..............so I know from experience that if only one wire is not connected right, it won't work. Can be frustrating as hell.

Edited May 23, 2009 by yellowdatsun

[240ADAM]

I've hooked up everything as far as I can see correctly, but sometimes it takes an extra pair of eyes to find your mistakes. There are two guides on HybridZ on for the turbo swap into an S30 and one for the Z31 ECU swap. Your right there is only a few wires to hook up and I believe I have follwed the guides and have them all hooked up to the correct locations. I was hoping to finish this swap my self, but at this point I just want it to run. So hopfully Jeff and Frank can figure somthing out.

[yellowdatsun]

Yep, on two of the swaps I have done I thought everything was figured out and wired correctly, and was pulling my hair out trying to figure out what was wrong. Both times it turned out to be a wire connected wrong. Fixed the wire are it fired right up.

 

If your not getting both injector pulse AND spark, something isn't connected right. Either where the EFI harness was connected to the chassis harness, or within the EFI harness.

 

Was the Z31 setup running in the 280ZXT prior to the swap into the S30? If it was all done at the same time this could be part of the problem, since the 280ZXT harness needs to be modified to run the MAF and later ECU. Just further complicating how much wiring needs to be done.

[240ADAM]

Unfortunatly the car didnt run before I yanked out the engine. The AFM that was in the car was water logged and didnt look like it would work and I tried to power up the original ECU and I could not get the light to come on, so I pulled the cover and low and behold a burnt spot. I decided to hook up all the Z31 stuff because of that. I know it will be a bitch to get running after switching all that at once, but I really had no choice.

[yellowdatsun]

Just out of curiosity, did you do all the fuel pump relay mods for the wiring?

[240ADAM]

No I have a 75 so I just used the stock wiring and hooked up a relay. The fuel pump comes on when the key is in the on pos.

[yellowdatsun]

Reason I ask is because I think I remember something about a wire going to the relay *and* then returning back to the ecu.

 

It's difficult to say what you'll need. On the standard 280ZXT setup there's an ignition hot wire that runs from the key to the fuel pump relay, then through the air ergulator, and then to the ECU. One of the signals it get's to know it's running. When converting a stock 280ZXT setup to run with the Z31 stuff, this needs to be wired, and the regulator can be bypassed, but the ecu still needs to see this as a hot ignition source.

 

Yet on the stock original Z31 V6 setup you can run fine without both the air regulator and the efi relay.

Edited May 23, 2009 by yellowdatsun

[240ADAM]

Jeff, Frank and I checked out my car and I do have everything hooked up right. So we took the cover off the ECU and things didn't look so good:mad:, now I need a turbo Z31 ECU, anyone got one?

[yellowdatsun]

Actually, you don't need a turbo ecu. Just use any Z31 ecu except the 89 turbo. The 89 turbo is a better ecu, but uses a totally different O2 sensor. I'm currently running an 85 non turbo ecu in my 81 ZX turbo, and it runs beautifully. The non turbo ones will run the car a little rich, but that's about it. Plus, the non turbo ones are a dime a dozen, where everyone wants a lot of money for the turbo ones.

 

So especially if you have the chance of blowing another one, definitely use the cheaper no turbo unit.

[240ADAM]

Cool thanks alot, I'm on the hunt!!!:D

[240ADAM]

Hey do you know if a maxima one will work, Its still a VG30?

[yellowdatsun]

I'm not sure if the harness is set up the same. I would assume, but not sure. In all the VG30 510 stuff I've done, having owned Z31's, and converted my 280ZXT, I've never heard of someone using the Maxima computer. Doesn't mean it wouldn't work, but I dunno personally. The normal Z31 ones are cheap enough, I'd use that just for piece of mind. Unless you have a Maxima one for free, then it doesn't hurt to try.

[72240z]

Hey do you know if a maxima one will work, Its still a VG30?

 

I just want to chime in and say I know for a fact the maxima uses a few different pins which would cause even more wiring alterations.

 

If the n/a ecu runs it a little rich does upping the boost lean it out a bit? :-)

 

I'm thinking about using a z31 efi for my l28et since I need to get a harness anyway. Can always go nistune down the road and what not.

[240ADAM]

So I went to the local pullapart today and got a 86' maxima ecu and guess what, I got spark. I have not tried to fire the car yet but I did hook up the ecu, spun the distibutor and the injectors were clicking and I got shocked from the spark plug wire I was holding:eek:. Later tonight or tomorow I will try to fire it and see how it runs. I'll keep ya'll updated.

[yellowdatsun]

Well your farther along now than you were before. Curious to see how the Maxima one works. The different pins could, or could not, be a problem. Just depends on what they go to. I have like 5 ecu's here at my house to play with. I always keep a couple good spares, and take one extra on road trips just in case.