Zed Head

A maybe helpful comment - the ECU's usually go completely bad, either running super rich or not running at all. Your lean popping symptoms indicate the need for more fuel, which is not a common bad ECU symptom. Also, I notice that you mentioned electrical testing but nothing about fuel pressure. Another potential cause. Anyway, good luck.

Your time, and your money. Might as well send the money to a member though. wheee! seems like a good guy and could probably use it for his project. Post #4.

Fascinating that so many of us adjust the AFM to try to fix this problem. I did the same when I first got my car and ended up buying a new one from MSA. But my test numbers were way off. Still I might have been able to make it work using the other atlanticz Z "tweak". I have two, maybe three, AFM's that needs this tweak to work. It's the most direct way to get it done. http://atlanticz.ca/zclub/techtips/tempsensorpot/index.html Forgot to say - put your AFM back where it was. Blue's technique is for recalibrating to factory specs., not tuning. Many people just read the theory of what happens and use it for tuning. But it doesn't seem to a linear full spectrum fuel enrichment, like the potentiometer is.

That's the right ECU. The problem might be from something else. We could probably offer some advice if you added some details to the "does not run right".

What's the number on yours? Share. Here's a Nissan Service Bulletin that I found on the internet a while ago. Looks like they all used the same, except for 1975, and 77 and 78 AT models. NTB94-097 (Nissan ECU Guide).pdf

You probably have multiple wiring problems. The Maxi-Fuse comes from somebody's Maxi-Fuse upgrade which means somebody has been messing with the wiring. Could be as simple as two wires touching or one pinched to ground. I would take a good look at all of the Maxi-Fuse block work and fix all loose connections, make sure the wiring matches the factory diagram (or atlanticz's page), and do some work with a meter. You won't learn anything at all by burning another fuse.

The above, the third part about restarting, does not match a blown fuse. Fuses don't fix themselves when they cool down.

I looked in the How To Rebuild book and can't find any sign that there's a difference in the L24 and L28 blocks besides bore. He doesn't mention the different timing chain guides either. Nissan probably did some minor mold clean up when they went to the N42 L28 block but if zcarnut can use the L28 piece on his L24 blocks, the bolt holes must be the same. It's probably a like-for-like piece, just so people get the same as what they're replacing. I've never seen anyone notice that before though. A new mystery. p.s. I was joking on the Kameari kit. Unless you're planning for 13,000 RPM.

That is weird. The L28 kit costs more, but wouldn't have the fuel pump drive cam. And if the L28 guide is better, why even sell the weak L24 guide. Maybe people just like to see identical replacements parts in their kits, so MSA gave them that to stop the questions. http://www.thezstore.com/page/TZS/PROD/10-2050 http://www.thezstore.com/page/TZS/PROD/10-2051 Maybe they've been doing it for a while but MSA now has Kameari parts. Upgrade your cam control! For just a few dollars more. http://www.thezstore.com/page/TZS/PROD/10-5470

Actually, one remaining question is "should you replace those bushings with PU bushings?"

If you do find that the internals of your 76 distributor are rusted and gummed up, the ZX distributor is a good option also, because it uses a high energy ignition control module and coil (so you'd want a newer coil too, projects always grow...). 1976 still uses a low energy coil and ballast resistor. But if the guts are in good shape, it might be worth keeping. I marked up a picture to show another simple way to check the breaker plate. But, they are almost always rusty and need lubrication. They are super easy to take out and replace and you'd have to work to get it in backwards (no offense to those that have managed to do that). It will only install the right way or 180 off, no gear teeth to worry about. It will only go in 180 off if the tang and slot are worn, and you can't distinguish the big half moon from the small one.. Take the big screw out, it might be very tight, gently loosen the vacuum module, it might be very tight, and gently pry it out part way with a screwdriver. It might be very tight. The breaker plate with the pickup coils on it should rotate. But, if you pull too hard you might break the bearing holder under the plate and screw things up. So it's dangerous. Were it mine, I'd loosen that big screw while it's mounted in the engine, give the module a little twisting to break it free, then remove the distributor and take a good look. The breaker plate comes off easily also, and you can check the centrifugal weights. The other way to check operation though, is with a timing light. Connect intake vacuum directly to the module port and see what happens to timing. Edited - backward arrow.

The only part that matters on the reluctor is the very edge of each tooth. That's all the pickup coil sees. You can shine up the rest but it won't affect performance. I'd be leery of any aftermarket reluctor because the precision of the timing depends on the precision of the machining. I'd rather have a rusty factory reluctor than a new aftermarket reluctor. Another way to check the breaker plate vacuum advance is to just twist it with your hands. But eyeball the edges first for rust. If there's any at all, best to take it out and clean it up. The balls will get stuck and the bearing holder will break. Not good. A common problem on the EFI cars is a lean mixture from the ECU. Adding the potentiometer to the coolant temperature circuit will help. Here's a good link, many do it. It's reversible if it doesn't work. http://atlanticz.ca/zclub/techtips/tempsensorpot/index.html

We should start a poll thread with all known suppliers listed and just keep track of who's good and who's bad. I've started two specific threads about problems but kind of feel bad that we don't recognize the good work. MSA, for example, did swap a bad mirror for a good one, after I called them. This would give anyone who does their due diligence a chance to see some real-time feedback. Everybody wins.

This is a timely thread. I thought I had a rear seal leak but now it looks like the pan gasket. Surprising how much oil can build up around the perimeter of the pan and slowly leak out over time. So did you use no RTV or sealant at all, just the gasket? Dry on a clean surface? Hylomar Blue is good stuff and stays pliable. Stays pliable so no need to worry about the V part of RTV. The transmission rebuild guys love it. http://www.hylomarsealant.com/

You can get a pressurized air bubble in the filter that doesn't really matter. The float bowls will still fill and that's what counts. But the 11.5 volts is not good at all. 12.6 is standard lead-acid charge. 11.5 is almost dead. But once the engine is running you should be on alternator voltage and that's when your problem happens. But you might be just running on battery power. Verify voltage while running. Low voltage can case weak spark. Found this interesting chart via the Google, post #2 - http://www.solarpaneltalk.com/showthread.php?20997-SLA-Battery-Possible-Discharge-Problem

The spindle pin removal is a popular topic of discussion. There is a ton all over the internet to look at: pictures, descriptions, horror stories, etc. Not to be too negative but if you had problems with the lock bolts, the spindle pins themselves will be tough. Sometimes they come out easily but not enough. One trick to get things started and allow some penetrating oil to get in is to put an old lug nut n the end of the spindle pin and spin the pin in its bore. After that, you can tap on the nut and see if the pin moves back and forth. From there it's just a matter of how far you can get it to move and what it gets stuck on. Worst case, people cut the pin in to pieces and press them out later. Here's an example, from Blue's work - http://atlanticz.ca/zclub/techtips/suspension/rearend/index.html And here's the hubs, which are also described in the FSM - http://atlanticz.ca/zclub/techtips/rearwheelbearings/index.html And bonus stuff - http://www.atlanticz.ca/index.php/tech-tips.html

Who is Art Singer and how does one buy parts from him? It's tempting to surf Al's site and find all of the stuff he's marked up (there's a bunch) but if he can offer a proper return policy and respond to people's problems that would be reasonable. But a big markup on RockAuto parts, with no returns allowed is just not right. The Wheeler Dealer show probably gave him a big bump in sales though. Easy money, no conscience required.

Could be running rich, or some oil leaking in to the cylinders Too much of one of those petroproducts, not being burned completely. Hard to be sure until you've tuned everything up. Found you an avatar, for those that haven't experienced the large scary bugs. They fly.

Really a shame that there's no response here.

If you want to drive it the most cost-effective route is to refill it with the proper water-coolant blend, drive it, and monitor the situation. If you want to work on it, there are myriad paths you can choose to address the ugly coolant. Not being sarcastic, just saying, some of us buy to drive and some of use buy for garage projects. Either way, a refill and some driving will tell you a lot about the situation. Only cost, with proper monitoring, is the coolant. You might find that the coolant maintains its proper color and clarity and the engine runs fine.

I think that you could easily measure all of those with a scanner, some data-acquisition software and a computer. Very common in the industrial/scientific world. But, maybe expensive. If you did the math you'd probably find that converting to Megasquirt, for data-logging alone, would be the way to go. The tuneable engine management would be a bonus.

I appreciate anybody's efforts to keep these old FSM's available. They are the most important thing, I think, that keeps these old Z's alive. But is your copy different from the Xenons30, or nicoclub copies? 1972 is available there. 1971, though, seems to be unavailable anywhere. On the other hand, maybe we should get copies of all of the FSM's in case those other sites go under, like web sites tend to do. I will ship my paper 1976 original FSM to anybody who will copy it and make it available to classiczcars.com. I don't have that ability. Does anyone know if Kinko's will do that work and how much? Whatever it takes.

The best thing to do is to read the label. If it says compatible, it's probably compatible. Color is a marketing tool, not a professional standard or spec.

Looks like the ZX uses the two longitudinal bolts, like the later 280Z's. From the 82 MT Engine Removal chapter. Weird that they have a special chapter for it, seems like it would be in Engine Mechanical. The transmission mount is considered the third engine mount. Not clear if you meant the crossmember or the rubber. If rubber, the part numbers should be the same at Rockauto or wherever. I have a ZX mount in the garage somewhere. Edit - added some Rockauto stuff.