Front injector bank not firing (1976 280Z)

[NicholasKoenig]

Called MSA and I had their pricing wrong. Their ECU is 325$ with the 200$ deducted! Forget that mess. 

Checked autozone and they have a Cardon re manufactured unit. Their core charge is only $11, which is great because for that low of a core I'll keep my old one and get CO to tinker with new transistors! 

With the promo code "20deal10" for autozone, you get 20% off, free shipping to your home AND a 10$ gift card. Heck yes! 

[Zed Head]

Pretty cool.  I love a good detective story.  I wonder if the transistor bases fail closed, in addition to failing open.  Question for CO.  Many ECU failures result in richness/flooding.

MSA is a site sponsor.  I like to let them know what the competition is doing so I gave them a some @'s below..  They have a business to run so have to be profitable, but competing with Cardone is a tough job.  Cardone is not known for high quality though, they're more high volume.  Beware, that savings might be temporary.  

And don't forget the member discount at MSA.  Somehwere out there is your member number which gives a discount at thier store (not sure of the percentage).  It used to be under your username but it seems to have disappeared again.  The core charges are the big deal killer though, especially since you don't know if your core is good, until after you send it in.  Plus you can't keep the old part for messing with, which is most of the fun with DIY.

@Joseph@TheZStore

@James@TheZStore

[wheee!]

Some pics of the insides of my ecu's from my 76

Edit:
Just read the other posts and see the situation is in hand now. Glad to hear you have a solution!

[KSRosser]

I had a similar problem once. Every time I closed my door the engine would stall. I traced it back to a loose solder from the distributor on the board. Have you checked every input for a read?


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[black gold man]

Detroit CL auto parts seller with ecu for your car.  https://detroit.craigslist.org/okl/pts/5863801513.html

[NicholasKoenig]

31 minutes ago, KSRosser said:

I had a similar problem once. Every time I closed my door the engine would stall. I traced it back to a loose solder from the distributor on the board. Have you checked every input for a read?


Sent from my iPad using Classic Zcar Club mobile

Trouble shooting lead to the ECU, all fuel delivery systems work, all six injectors were functional, distributor/coil/wires/plugs all functional, even the wiring harness checked out ok. Captain Obvious checked the suspect transistor on my ECU and to my knowledge, they were functioning subpar. Enough to read something but not enough to fully function and fire the first bank. 

[Zed Head]

1 hour ago, NicholasKoenig said:

Captain Obvious checked the suspect transistor on my ECU and to my knowledge, they were functioning subpar. Enough to read something but not enough to fully function and fire the first bank. 

That's interesting.  I tested mine, the "bad" ones that I removed, via a simple multi-meter test and they tested OK.  Leaving me wondering what really happened.  I still need to put that ECU back in and give it a ride, just to see.

[Captain Obvious]

Nicholas, Glad to help and it was really nice meeting you. It was such a nice driving day that I took the long way home. It won't be too much longer before my Z is packed away for the winter.

 

So the details on testing your ECU was that both transistors looked OK with just a meter test, but because of the somewhat unusual internal construction of the output transistors, testing them with just a meter might not tell the whole story. And that's what I think is happening with yours. Not that you should ever need to know or care, but the ECU output transistors employ an internal construction known as "Darlington", which means there are actually TWO transistors packaged together. And because of this construction, you can't always get a good handle on what's going on inside with that simple test.

 

Here is where I think your transistor failed, and this failure mode can't easily be detected with just a meter:

As for the replacement ECU, I'm sure glad I challenged you on that core charge from MSA... Bad that the price was higher than you expected, but good that you learned that before it was too late! Once you have another ECU, buy one (two would be even better) of those NTE247 transistors and I'll be happy to install them for you and make sure all six outputs are working.

 

In the meantime... Get welding on that metal work!! 

[Joseph@TheZStore]

Ladies and Gentlemen,

Sorry for the slow responses, it was, once again, my screw up. When I set James up in this forum, I forgot to turn on email notification... Fixed... Again, James will follow up on this as needed.

Of course some subjects also may require more than just a quick answer, like in this case.

As was mentioned in this discussion already, we've also had mixed results with some Cardone products in the past. In the case of electronic items like ECU's and Air Flow Meters, we trust our local instrument company gurus, who we've used for over 20 years, to do it right. Not saying Cardone's rebuilds aren't good, they may be just fine. However, there are other thoughts to consider as well:

Note that the only one they show available is supposedly for 75-76 AT, and 77-78 Federal, regardless of model number of the ECU. While it can be a subject for debate, according to Greg, our 20+ year rebuilders, and lots of experiences, this is simply not correct. There are multiple model numbers within those applications, and most shouldn't be mixed. Some numbers can be interchanged, and our rebuilders determined that decades ago, but many within that application range should not be.

While we do have a fair group of ECU cores that can be rebuilt ahead of time, with Motorsport you can also have your own unit rebuilt, which can be the best option when the car isn't needed as a daily driver. It is also better not to rebuild them, and then leave them sitting in a warehouse for years, so we don't have all the cores we have rebuilt ahead of time. If you do successfully conclude that your ECU is the problem and needs professional rebuilding, you can give us a call with your ECU model number, and we can check our core stock, or we can rebuild your specific ECU. That brings up another good point, the ECU, just like the Air Flow Meter, often gets blamed for problems that it isn't causing, so the rebuild doesn't end up solving the issue. Between the factory service manual, qualified technicians, and the vast experience of many helpful Z enthusiasts like on this forum and in this discussion, you can test to confidence about what is causing your specific issue. Testing by replacement can get expensive and frustrating.

Finally the significant core charge increase was a determination made between Greg, Sal, and some representative customers many years ago, as the best option for the Z-Community at large to continue to have them available as long as possible, since ECU's are not being made anymore. Without much incentive to send the unit back, then the available group of ECU's would continue to dwindle much faster, with units sitting on garage shelves instead of being available to another person. This likely explains why Cardone has no stock available for 75-76 Manual Transmission, or 77-78 California. Our guess is that many larger companies don't care much about that aspect, but Greg does, as our entire business is Z cars. In almost any possible case, the only thing that would cause an ECU to not be viable for rebuilding (and core refund) would be if it has been taken apart and damaged, or flooded. If that is suspected, we recommend sending your own core in for rebuilding, as there hasn't been much over the years that our rebuilders haven't been able to fix.

Just message James with anything you need. He is always quick to help (well, when the "computer/internet guy" (yours truly) doesn't screw up the settings so he doesn't know about it...)

[Zed Head]

Have you considered reconsidering your core charge?  Maybe get some economists to help?  Risk/reward. opportunity cost, etc.  You have a nice case study here of how the high core charge drove a customer to the less expensive alternative.  $400 seems like it came from nowhere.  It's more expensive than the rebuilt part, which makes no readily available sense.

Also, has anyone considering buying cores?  Many of us out here have old AFM's that we've picked up cheap, as spares.  I often see good cores in the wrecking yard, with corroded electronics.  No need to try to save them though because there's no market for the core.  Off to the crusher.  I'd probably send them to somebody $20 each, if they wanted them.  Maybe even free if somebody asked.

[grannyknot]

But if you can't afford an old collector car, then you can't afford an old collector car.  I just recently I tried to get the ECU for my 1987 bmw M6 repaired by Programa, as far as I know they are the only game in town for to repair that particular ECU, they wouldn't look at it for less than $500, they wouldn't accept my core and send a rebuilt unit for less than $500, they wouldn't even test it for less than ...

Although I didn't care for Programa's price and instead went with megasquirt, I can see why they need to charge so much, in order to stay in business you can't have a bunch money tied up in units sitting on the shelf waiting for someone to buy them or maybe not buy them. Now that the rest of the car collector industry has turned their attention to our Z cars I think the days of inexpensive Z ownership are almost over.

Not really arguing with you ZH although I know you enjoy a good debate more then most  just saying I understand why they are asking so much for a core, it ensures there is always a unit ready to rebuilt for the next guy.

[Zed Head]

 I understand core charges also, but this one seems irrational, with no real calculation behind it.  Picked from thin air.  Just makes you wonder.

Aside from that, it's a lost sale and drives a potential customer out to look at alternatives.  So, big picture wise, they probably lose more than just the single AFM sale.  Once you go CARDONE, you probably stay there until you get a bad part..

The only reason I @ these guys is so that they can tune the business to keep the customers happy.  Staying quiet out here while people talk about why they didn't buy from MSA doesn't help anybody.