Zed Head

Usual pile on... I found what is supposedly a 1979 280ZX ECU on the internet with some good pictures. I don't see a 6801. Maybe there's an earlier controller in there somewhere? I'm not an electronics guy. The guy has a nice web site. If you click on the picture you can scroll through all of them and blow them up to a good size with another click. https://www.importapart.com/product/79-datsun-280zx-2-8l-l28-ecu-ecm-pcm-engine-computer-a11-616-420-oem-1869/

I found an old thread that might have some pictures. Haven't gone all the way through it. Funny though, Nissan uses the word "compute" in describing how the ECU (1978 I think) sets the injector pulse length. It's on page 3, post numbers are gone. Edit there's only a few pictures of early 280Z "ECU"s.

But what do you mean by "computer"? Does the controller contain a program? Does it perform computations? Or does it just convert one electrical input in to another? I don't know. I found some interesting things about it. It looks like it does contain programming, I wonder how complex it is. It would be interesting to see some of the code with comments. I assume that the code/program would be considered digital but the inputs and outputs not. https://www.cpushack.com/2017/12/07/cpu-of-the-day-hitachi-hd6801s0pj-automotive-6801/ http://www.bitsavers.org/components/hitachi/_dataBooks/U24_Hitachi_6301_6801_Assembler_Text_Editor_Users_Manual.pdf So, going backward from 1983, do you know when the Hitachi controller was introduced in to the ECU's? I know that the FSM's say that the 1979 and later ECU's cannot be plugged in to 1978 and earlier systems, even though they use the same connector. The pinouts are different, maybe because 1979 and up contain the controller. Does 1979 contain the controller and 1978 does not? Referring to what HS30-H said above, maybe the controller was introduced in to the ECU's also in 1979, along with being used in the ECCS. Only commenting to learn some new stuff. I started watching repair videos for modern vehicles and learned that they have all kinds of modern tech with high speed and low speed communication networks, and numerous "modules" each usually with its own controller, communicating on the networks. I think that even the intrument cluster in my truck has its own controller. Crazy. Always something new to learn...

Thanks for the clue. I had looked in the 1982 FSM and found the combined EFI and ECCS descriptions, letters only, but should have started at the beginning. In the first 280ZX use of the ECCS, the 1981 Turbocharged 280ZX, they created an ECCS-only Supplement chapter, where they actually used the words, as defined above. Image below. They do call it a "micro-computer" in their description. I'm still not sure though that it does computing, in today's sense of computing. Besides the fact that it's not digital. (Sorry SteveJ, now that's really pedantic, Just having fun.). But it was still early days for computers, and I think the definition still varies today. From the 1981 Turbo Supplement Engine Fuel chapter -

Not bad. There are still good Z project opportunities popping up out there. https://bringatrailer.com/listing/1972-datsun-240z-357/

Just for fun - CECU. Figure that one out.

I didn't even get my explanation right. I used the chapter label, EFEC, instead of ECCS. I'm not really sure what ECCS stands for.

The 280Z control system could easily have ended up as the EFIS.

Actually, the the ECCS was introduced with the 280ZX's. The ECU is used in both but started with the 280Z's. Generally, ECU stands for Electronic Control Unit or EFI contol unit. Edit - not sure what ECCS stands for. Of course, it's all translated from Japanese, so the words might not make the most sense in English. But that's how ECU and ECCS are used in the FSM. From the 1982 FSM, below. Might be the the ECCS "computer" should actually be called the ECCSU. There have been some discussions about what should be called a computer. I don't think that either of these actually do any number crunching.

I had forgotten about that. Reminded me that you have to lock the door with the key from the outside after you close it, if you want to lock it and leave it. Of course, based on the above. The knob is only for locking yourself in. I used the knob to work the mechanism free becuase I was afraid that I would break the key.

I remember the lock mechanism on my 76 being almost impossible to move even with the knob and cylinder attached correctly. It might be that you just need to get a better grip on the part that the knob rod attaches to and pull harder. Might be worthwhile to fabricate a new rod and attach it to give you something to pull and push on. With lubrication and some manual working the mechanism on mine eventually loosened up. The car had sat for many years before I got it.

Here's an old post from TerrapinZ with good measurements. Just noticed that posts don't have numbers anymore. Bummer. It's about 1/3 down page 12 if the link doesn't take you directly there.

I should have mentioned the distributor itself also. They are known for worn bushings allowing the reluctor wheel to contact the stator ring, breaking things. If it won't start with fluid, it's not going to start with gasoline. Good old Blue wrote up a thing about them. The magnetic pickup can fail, there's a test for that. The air gap can be off, there's a measurement for that. Described in the Electrical chapter. https://www.atlanticz.ca/zclub/techtips/distributorrebuild/index.html

You said but you didn't describe. Try starting fluid. If it starts but runs poorly, it's not fuel pressure.

Is the spark strong and blue or weak and orange? I had an ignition module go bad and it showed spark. But the engine would only start with starting fluid. As far as fuel, the fuel pressure regulators tend to start leaking down if they sit for a long time. The seat n the FPR gets corroded. They will maintain pressure while the pump is running but leak down quickly once it stops. The simple test is to clamp the feed or return lines and see what the pressure does.

I had the same thought about needing some angle being necessary to work the needle bearings. Side note about the "AI Overview". It is basically a boiled down compilation of everything available on the internet. Including all of the garbage and nonsense. The tech marketers want us to start believing what the AI algorithms produce. But, really, it should all be ignored and only verified professional sources should be considered. At this point in time, "AI" is good for entertainment purposes only. If you really study the statement below you'll see that it actually says very little, and some of it makes little sense. Like "allow the shaft to change angle". Empty words, really. No offense intended. It's just another of those things to be worried about. The word intelligence does not guarantee intelligence.

Not clear what year 240Z you're driving but Nissan moved the diff back because of vibration. I can't find a reference but it's been well-discussed. The shorter "pre-modification" propeller shaft was/is popular for people doing the 71C transmission swap because the length was perfect. Anyway, maybe you're just experiencing the reason Nissan made a change. I think that it was actually mid-71 but not sure.

I found the option to click to get the site back to the thread title view. Upper right, next to the auto-update comment, pasted an image below. I guess that the default is post-by-post. Not sure if it sets a cookie or not. Might have to click it each time.

Here is the basic answer to Mike's comment "Or just log in...". On top of the above is the effort expended to peck in the email address and password. If you use your computer for other things like banking the constant username and password inputs gets tiresome. And, a new change - not really sure why, but the "Topics Last 30 Days" option is gone now. I suggested that way back when so that people who had not been on the site for over a day could look back over the previous few weeks. At the time the "Load More Activity" thing didn't go back very far. So if you missed a few days and nobody posted, the thread was lost in the Forum sub-titles. It's been very handy, especially when the posts were categorized by Topic. If you remembered a thread about somebody's clutch replacement and wanted to see how it had come out you could go back and find it. Can't do that easily anymore. The new post by post list doesn't work well. parman's thread is entertaining but when the whole page is parman...? I also notice that the old problem is back on the "Topics Last 24 Hours" page. Each click takes you to the first post if you're not logged in. More clicking and scrolling required. That's probably the key message here - reduce the number of clicks and scrolls required to get to the new stuff. Just trying to offer some constructive feedback. I hate to be critical but the site was working really well before, like a well-tuned Z. It has a few misfires happening now.

The Activity page now lists each post instead of each Topic. Is that intentional? All a person sees today is a long list of parman's thread posts. Not much interaction there either, it seems to be a collection of old pictures and a story. Nothing wrong with that except that it's dominating the "feed".

When did the work on it start? It wasn't 18 hours ago. Is it done now? What are your plans? Edit - is this the 4 year restoration car you mentioned in a different post? Those first pics are four years old?

Is it a 1971 249Z? I see a clutch pedal with low wear, a sign that it's low mileage. Must be a manual transmission. Any more details? Looks like a fun project. There'a thread on the forum, I think it's called "waking the beast" or something like that. You should find it and read it before even spinning the engine. It's possible that it might not be too rusty inside. But unlikely. One of those bore scopes will tell you a lot. Good luck. Edit - found some details on your profile.

Thanks for the tip CO, I didn't know that other pages worked differently. I'll just start using the main Activity page now and avoid the aggravation.

Without it, a person has to find the place to click and click multiple times, plus scrolling to the bottom of the page, to get to the new post at the end of a multi-page thread. Going to the first post of a three page thread is pointless if you've already seen the three pages. If you're on a "phone" it's swipe swipe swipe, touch, swipe swipe swipe. It's why the software developers created the "X hours ago" link. That is its purpose. Go directly to the new stuff. It's odd that it doesn't work on CZCC. You were using the same platform as Hybridz. You can jog over there and check it out. https://forums.hybridz.org/discover/

Click on X hours ago - go to post that happened X hours ago Click on title of thread - go to first post in thread This how most other forums work, across the internet. This is how CZCC used to work, logged in or not. We've all become used to this format. Something changed when you started customizing.