(another) l28et 280z

[Jesse OBrien]

New facts:

 

I've verified that my ECU is getting power. One of several green wires in the engine bay (the thickest green wire, ~14ga) powers the ecu and injectors, it turns out. Some wiring diagrams say that should be red, brown, or white/red ... but it's been inconsistent. On my car, it's green.

 

I'm having a tough time finding specific differences between the 81-82 wiring and 83 wiring, but the 83 appears to be the most problematic so that's all I could find documentation for. I still have no idea which engine year I have. The best documentation is still the http://forums.hybridz.org/index.php/topic/34469-a-quick-fi-and-ignition-280zxt-to-s30-turbo-swap-guide/ series from bumble zee, but it still has a lot of holes. For example:

1. What does the ignition harness look like?
2. Are there more relays on the 83 than on the 81-82?
3. Exactly which sensors are required to have the car run?
4. Where is the FI relay physically located?
5. What does the FI relay look like, and how is it actually wired?
6. Where is the fuel pump relay physically located?
7. How can I identify which ignition system I have?

After realizing that I really don't have enough facts to go on, I started labeling all the disconnected connectors I have to establish a single source of truth. I don't have a lot of time remaining, so I'm looking for specific facts. Because of that, I'm organizing the information that I already have, so hopefully some of you who have actually seen an in tact system can help me to identify the unknowns that I'm dealing with. Bear in mind that the previous owner had a friend's cousin's dog's brother's owner do some of the wiring for him, and I received no documentation on what was done or wasn't done. Please feel free to add notes or purpose information into the following spreadsheet.

 

Canonical Wiring Identifcation Sheet

 

At this point, I have no spark (the coil's + source has +12v, but no power is coming out of the output plug to the distributor). I don't have a good way to test the injectors, but I did verify that the ECU has +12v for all 6 leads to the plugs (the bottom row on the three-row connector). Now that I finally have power to the body, I can start diagnosing more important things like ECU input/output, ignition wiring, and fuel pump wiring. With your help, I could just power through the cold tonight and have it running in the morning.

 

Just in case any of you can't see the document I linked to, I've attached a PDF working copy here: 75 280z and l28et Wiring Reference - Sheet1.pdf. Once I have all the connectors documented, I'll republish it with all the latest info.

Edited November 17, 2013 by Jesse OBrien

[tooquick260]

The relay you had on the fender should be the ignition relay. here is a pic of mine.

 

 

 

here is the connector that it attaches to that also has the wiring for the fuel pump.

 

 

Here is the other side.

 

I will try to help as much as I can. I am in WI and car is in FL. Have to go by memory. I may be able to get my brother to look as well.

Edited November 28, 2013 by tooquick260

[Jesse OBrien]

Hugely helpful, but do you know which connector that actually is? Looks like 4 wires, where mine seems to have a spare wire stuffed into it.

[tooquick260]

 

Do you have this?

[tooquick260]

Hugely helpful, but do you know which connector that actually is? Looks like 4 wires, where mine seems to have a spare wire stuffed into it.

 

You should have 2 of these. One for igniton and one for fuel pump relay.

[Jesse OBrien]

You should have 2 of these. One for igniton and one for fuel pump relay.

Only one, where would the other be located (physically)?

 

I have two versions of that diagram printed out, but it's specifically for an 83 l28et and doesn't indicate the physical location of any of the components.

Edited November 18, 2013 by Jesse OBrien

[tooquick260]

My car is a true hybrid. I believe both relays are on the passenger side near the fusible links. I believe the 5 wire would be the fuel pump relay. That is run from the 2nd pic i sent you.  The 2nd pic is from the ecu. the 3rd is the other side of that connector. There was a blue with red stripe wire that is the signal I believe, if you follow the diagram pic I sent you you should figure it out. Going to be tough with you color blindness issue. 

 

The 2nd/3rd pic shows the black/white stripe that needs ignition on.

 

Blue/red stripe goes to relay

[Jesse OBrien]

My car is a true hybrid. I believe both relays are on the passenger side near the fusible links. I believe the 5 wire would be the fuel pump relay. That is run from the 2nd pic i sent you.  The 2nd pic is from the ecu. the 3rd is the other side of that connector. There was a blue with red stripe wire that is the signal I believe, if you follow the diagram pic I sent you you should figure it out. Going to be tough with you color blindness issue. 

 

The 2nd/3rd pic shows the black/white stripe that needs ignition on.

 

Blue/red stripe goes to relay

I only have one set of fusible links, and only one relay on that passenger's side. I'm not saying there shouldn't be one, but is it possible there is a difference between the year I have, and the year you have? What year l28et is your engine?

 

It looks like the PO removed that connector altogether on mine, or it never existed on my year. I just took a look, and it's just not there (along the driver's side frame rail, in the engine bay). I'm guessing this mess used to be that connector:

Edited November 18, 2013 by Jesse OBrien

[tooquick260]

Ha..... I have a L26 motor that came in my 260z. I put a P90 turbo head that has been modified. The harness I used is from an 82, used a 83 distributor oil pump setup to have the optical reader for the ecu ignition. Ran a 83 turbo ecu. Now have z31 ecu, with z32 maf.

 

My stock wiring has 2 fusible links.  

[Jesse OBrien]

Hahahaha so your configuration is about as nonstandard as possible. Got it. Still, identifying parts is massively helpful to me. I'm really pressed for time, so you couldn't be providing this reference information at a better time.

[tooquick260]

One of your pics shows 2 fusible links

[tooquick260]

The five wires 2 green, blue/red, white, yellow is definitely for the fuel pump relay.  You can live with out that and wire pump to ign on, till you get everything setup

 

Do you have the relay for the ignition wires

[cygnusx1]

 I have successfully performed two L28ET into S30 swaps.  Both were into 280Z but my experience in both cases revealed faulty ECCS connectors.  Horrible running, popping, poor idle, rev-limiting, lean running, all of the above are symptoms of bad connection at the two ECCS plugs.

 

When you get to that point, push and pull each wire, directly at the back of the connectors, with the car running, and you will instantly identify the problem areas.  Adding dielectric grease, and carefuly "preloading" the pins in the ECCS connector by slightly bending them to one side, seems to alleviate the issues.

 

Not sure if it helps, but I have a pretty simple wiring schematic for the swaps over in the downloads section of hybridz.

 

http://forums.hybridz.org/files/download/4-turbo-swap-wiring-diagram/

Edited November 18, 2013 by cygnusx1

[Tony D]

On some of mine, out of movement of harnesses and wanting to clean things up, or shorten/extend this or that...I replaced stuff with Weatherpack GM-Style connectors...

 

Some of those ECCS Plugs were literally filled with green corrosion byproduct, and it was "I don't have the time for this crap!" Snip, Crimp, and Stab and I was on my way.

 

I think this ties in to my lack of problems after swaps like Cygnus mentions. Whatever is valid in chassis originally is compounded when you swap and disturb maybe tenuous connectors at best then hope they reconnect later.

[Jesse OBrien]

 

One of your pics shows 2 fusible links

 

 

I definitely only have one fusible link connector (it has two fusible links in it).

The five wires 2 green, blue/red, white, yellow is definitely for the fuel pump relay.  You can live with out that and wire pump to ign on, till you get everything setup

 

Do you have the relay for the ignition wires

There's only one relay in the engine bay, and it sounds like that's the fuel pump relay now. Unless the ignition relay is bundled up under the driver's side dash behind the firewall, I haven't seen anything that resembles ignition wires. I have a coil (unknown model, don't know if it's from the l28et or l28e and don't know how to distinguish between the two) that appears to be connected to the end of the headlight wiring bundle. It has good + and - on its two posts, but I have no output from it. I think I've identified the underdash ignition connector (on the ECU bundle) but I'm still putting together all the pieces from BumbleZee's howto with that. Those are my facts, at this point.

 

 I have successfully performed two L28ET into S30 swaps.  Both were into 280Z but my experience in both cases revealed faulty ECCS connectors.  Horrible running, popping, poor idle, rev-limiting, lean running, all of the above are symptoms of bad connection at the two ECCS plugs.

 

When you get to that point, push and pull each wire, directly at the back of the connectors, with the car running, and you will instantly identify the problem areas.  Adding dielectric grease, and carefuly "preloading" the pins in the ECCS connector by slightly bending them to one side, seems to alleviate the issues.

 

Not sure if it helps, but I have a pretty simple wiring schematic for the swaps over in the downloads section of hybridz.

 

http://forums.hybridz.org/files/download/4-turbo-swap-wiring-diagram/

That doesn't surprise me at all, the l28e connectors were simply falling apart on me. The ECCS connector is pretty solid, I've been poking the pins like mad with a test light, but they don't flicker or wiggle. At this point, horrible running would make my day.

 

Winter plans involve a pile of reliability improvements, including a new from-scratch wiring harness and Megasquirt, fuses that aren't made of glass, and properly weatherproofed connectors. Today, it just needs to go, with both spark AND fuel!

 

On some of mine, out of movement of harnesses and wanting to clean things up, or shorten/extend this or that...I replaced stuff with Weatherpack GM-Style connectors...

 

Some of those ECCS Plugs were literally filled with green corrosion byproduct, and it was "I don't have the time for this crap!" Snip, Crimp, and Stab and I was on my way.

 

I think this ties in to my lack of problems after swaps like Cygnus mentions. Whatever is valid in chassis originally is compounded when you swap and disturb maybe tenuous connectors at best then hope they reconnect later.

These connectors aren't as bad as most, based upon my experience. I'm sure they aren't perfect (I'm not crazy about these connectors even if they were brand new), but through all the test-light pokes and prods I've been doing, I haven't had any flickering signals or wiggling pins. I believe the hardware should be good to go, if I can sort these wires out and get the critical components connected to each other.

[Tony D]

Frankly, a "test light" doesn't cut it for diagnosis with this system. A 62 VW Microbus maybe....an 83 ECCS? You're solidly in multimeter era diagnostics at that point.

 

The only guys using test lights to diagnose systems in 83 were old techs at domestic dealerships that were ready to retire and refused to learn to use a multimeter.

 

The right tools for the job return better results.

[Pharaohabq]

The relay you had on the fender should be the ignition relay. here is a pic of mine.

 

 

 

here is the connector that it attaches to that also has the wiring for the fuel pump.   <This is PLUG 3 on the EFI diagram>

 

Here is the other side.

 

 

I will try to help as much as I can. I am in WI and car is in FL. Have to go by memory. I may be able to get my brother to look as well.

 

Plug 2  is the ZXT female plug in Cygnus' Drawing.  Plug 3 also appears to be the 280z female plug in his drawing.

[Pharaohabq]

I only have one set of fusible links, and only one relay on that passenger's side. I'm not saying there shouldn't be one, but is it possible there is a difference between the year I have, and the year you have? What year l28et is your engine?

 

It looks like the PO removed that connector altogether on mine, or it never existed on my year. I just took a look, and it's just not there (along the driver's side frame rail, in the engine bay). I'm guessing this mess used to be that connector:

It's hard to say for certain, but your spreadsheet  shows wire #11 blue/red and wire #12 Blk/White as going to the Fuel Pump Relay,   If that's the case and these wires went to the missing <Plug 3> then #ECU+ (thicker green) could go to Pin 16 on the ECCS, for the neutral safety switch and .    I really think you're right, that these are the wires that went to Plug 3.  

 

The Yellow looks like the Water temp and the White looks like the AC Fan relay Also from Plug 3.

 

If you look at the 83 ZXTurbo wiring diagram here, at the bottom right  shows plugs 1, plug 2 and plug 3.   Plug 1 is a Power Green and a Brown, which could be  Your #9 and #10  Looks like it's actually <Plug 1>  Fusible link the #10 and #9 together and you should have fuel.  Assuming the pump is connected at the other end.

 

That green box is the EFI (fuel pump) Relay.

 

I assume you've already downloaded the ZXTS130 FSM's from here: S130 280ZXT.   Too bad you're so far away, or I'd help you figure it, or at least get it moved to a storage facility.

[cgsheen]

 

That green box is the EFI (fuel pump) Relay.

.

 

Ya, It's the EFI Relay - the Fuel Pump Relay is a completely different part.  Ordinarily you'd use your existing (stock) 280Z relay and re-wire it to be triggered by the new ECU - or - wire in a new simple relay to pass power on to the fuel pump.  It's important that the ECU controls the fuel pump for safety considerations.

 

Sorry I didn't read the whole thread - did someone tell you the stock L28ET coil has an Ignitor strapped to it?  The stock 280ZX Coil/Ignitor have a harness seperate from the ECCS (engine/ECU) harness.  If you don't have it, you can use the Black/White (+12V @ IGN ON) from your stock coil (+), AND the stock Blue (to get Tach signal), BUT you need the signal from the ECU to the Ignitor and the amplified output from the Ignitor to fire the coil (-).  If you don't have a stock Coil/Ignitor you can use an appropriate coil and a GM HEI Ignition Module (threads beyond count about using a GM HEI...)

Edited November 27, 2013 by cgsheen

[Jesse OBrien]

It's been too cold to work on this outdoors, so I'm ordering all the supplies for an MS1 kit this weekend and having a friend organize it into a plug-in-ready kit for me (in exchange for some cash, of course). That way I don't have to deal with any pre-existing problems, and I have known-good brand-new EFI for somewhere under $1k, after all is said and done. He'll assemble the components, load the firmware and a base tune, test it on his 83 l28et, and ship it all out to me so I can get it around the block.

 

From there, I can FINALLY start tuning and stop wondering which wire is which (the MS harnesses are labeled intelligently, none of this color-coding nonsense). With a fair amount of luck, I'll be able to drive it to the house I'm planning to start renting on Feb 1. I'll keep the updates rolling in once there's something worth mentioning.