Fi Ecu Mods And Differences?

[wheee!]

Thanks much for the pics of that ECU with the DIP packages. Unfortunately no new info. Those are the exact same part numbers that are on the original round heat sinked versions. Still custom, still no datasheets in the public domain, and still made from unobtainium.

So have you tried that newer ECU in the car yet? Just to make sure it works?

I have never started my car... It turns over but I have no fuel. Either a dead pump, dead relay or clogged line. Got spark, but no fuel. I suspect the pump. But as I was planning a complete teardown, I haven't put a lot of effort into starting it. Maybe this spring...

Sent from my iPizzle ringy dingy device....

[wheee!]

• The good thing is that Suprlen says the Hellfire ECU can be swapped-into the Zed's ECU frame, and still use the OE connector.

That will be a good thing all right!

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[Captain Obvious]

cygnusx1,

 

Not sure what you're asking about the knockoff version...  L-Jet was used on lots of other cars other than the 280Z and some of those other cars continued to use improved versions of the L-Jet for a number of years after the first gen Z ended. I'm not saying that anyone is using knockoff versions. What I AM saying is that I've been through those docs you found and after study, it's clear to me that the ECU under analysis by the author is NOT from a 280Z.

 

Why do I say that?

- Because the pics of the boards are significantly different than the ones in our Z's and is clearly much newer production. I know that because there are several DIP IC's used and the board is CAD routed instead of the old hand routed boards that we use.

 

- The component designations used in that old info do not exist on the boards used in our Z's. We do not even HAVE an R616 or R758 for example.

 

- There are a few references to the use of a lamda sensor. They started including a lamda sensor input in the later years of the L-Jet, but that wasn't until the 280Z was out of production.

 

So what I'm saying that I think the info you found applies to a newer version of the L-Jet that was used after the 280Z production ended. There are a few references to Alfa Romeo in the docs so if I had to guess I'd assume that's what he was working with.

[cygnusx1]

Yes, I noticed the lambda reference, and the rev limiter, which the S30's don't have.  I wonder if any of that L-Jet resistor info is translatable to the S30 boards, since they are of the same L-Jet family.  I was mainly wondering how much of it is JECS design, and how much of it is just straight copy of the Bosch L-Jet design.  The experiment could always be duplicated, so that the S30 ECCS could be more "tuneable", but in this day and age, it is much more wise to replace the whole thing with a modern programmable unit.  

[wheee!]

I agree 100%. Newer is always better and more tune-able. I haven't seen a Megasquirt system in person but for some reason I am drawn to the Hellfire option, probably because of the name...

Now all we need is someone to finish it!!

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[TomoHawk]

The Hellfire was designed by a Zed owner for the Zed owners.

[cygnusx1]

I use the MS2 in my 280Z, but played around with the factory ECCS for years before I made the switch.  Having said all that, the factory ECCs was VERY good for its time.

Edited March 8, 2015 by cygnusx1

[Captain Obvious]

I was mainly wondering how much of it is JECS design, and how much of it is just straight copy of the Bosch L-Jet design.  The experiment could always be duplicated, so that the S30 ECCS could be more "tuneable", but in this day and age, it is much more wise to replace the whole thing with a modern programmable unit.  

 

I don't know how much of the design of the boards was done by Bosch or by JECS. I haven't researched the origins of the two parties involved, other than a quick snippet from Wikipedia:

 

"JECS was formed in June 1973.[1] It was a joint venture between Robert Bosch GmbH, Nissan Motor Co. and Diesel Kiki Co., Ltd.. It enabled Nissan to use Bosch's engine control technology, and gave Bosch access to the Japanese market."

 

I suspect the concept, original schematic, proof of concept demo board (probably with NO IC's at all), and of course patents were developed by Bosch, but the implementation (and integration of some of the electronics) was done by JECS.

 

As for the portability of the resistor designations in the info you found back to our ECU's?  Unfortunately I doubt there is any portability at all. I agree that it would be neat to have the experiments duplicated with our generation of ECU, but I've not seen that done. The closest I've ever seen is what you dug up.

 

I've poked around a little and have done some reverse engineering, but just enough to be dangerous. I also agree that time spent on reverse engineering the old one might be better spent working on something newer.

[wheee!]

I have installed the newest version of the ECU (with IC's) into the car. I played around with the car a bit this weekend and turned it over again, just to see what happened. No fuel is being pumped so once I diagnose where that fault is I can hopefully fire this engine up at least once before I tear the whole car down!

I have the FI bible so it shouldn't be hard to source the fault. Just need decent weather to work in the garage!

Sent from my iPizzle ringy dingy device....

[Captain Obvious]

Good. You have to start from ground zero. Just remember that the ECU has absolutely nothing to do with whether the pump will run or not. The fuel pump should run:

 

- any time the key is in the START position, and/or

- any time the key is in the ON position and there is air flowing through the AFM.

 

So step one... Pull the small black/yellow starter solenoid wire off the starter, turn the key to START and listen for the pump.

 

If it doesn't run, check for power back at the pump and if you have power there, you need to check the pump integrity. If you don't have power there, then you need to start backing up to find out why.

 

 

[wheee!]

Pretty much what I had in mind. Thanks for the confirmation! I think it might be a bad pump/bad connection as there is a lot of corrosion under there and I'm not confident the connections are good...

Edited March 10, 2015 by wheee!

[rossiz]

another way to test the fuel pump is with the engine not running and key in the "on" position pull the spade connector off the oil pressure sender - pump should start up and you'll be able to hear it swooshing through the return lines from the engine bay.

 

edit: i just saw from your signature that you have a '76 - i think your fuel cutoff switch might be in the AFM, the oil-pressure switch was used after 77...

Edited March 10, 2015 by rossiz