We are using the distributor from a 280ZX which uses an integrated (e12-80) ignition module. It is a common upgrade and bolts on.

No, the drive shaft for the distributor is offset keyed, the dizzy only mounts one way.
Yes, we have a timing light and it says our timing is correct (at least statically)...certainly close enough to get some action.
Right now she spins and spins without any indication of firing.

I'm going for the coil next.

 

Random. Do a compression test if you haven't.

I know you checked the chain and marks on camshaft and crankshaft, but at this point I'm not trusting anything on that engine. As in sprocket marks. I'd take the valve cover off and see if the rockers on cyl 1 are a lil' loose to make sure you are really at TDC cyl. 1 when the camshaft and crankshaft say so.

 

Replace the coil! I truly want to see that this thing runs before S moves!

 

I wish I lived in Denver. It should not be that hard to get this thing to pop.

 

New coil, distributor cap/rotor in hand (actually, sitting on my passenger seat but you get the idea).
This morning I'll go over, reinstall the fuel rail and hook up the new parts.

I wish you were here too, Tony.
Be nice to get a fresh perspective because I'm sure this is just a simple mistake I'm overlooking and having missed it so far, I wonder if I'm capable of seeing it now.

We'll know this afternoon.

 

Oh, the suspense Keeping my fingers crossed for you guys.

 

Previously I had said "No, you can't" but that is only technically true.
You can install the distributor (and oil pump) drive spindle 180° out...and that's what S. did.
The new coil did nothing, but that's not a surprise after the timing issue was uncovered.

So, today I'll fix that.
Possibly my most hated procedure, there is nothing fun about it.

Car goes up in the air, then the swaybar comes off (because it's right below the oil pump), then the oilpump and drive spindle come out from the bottom.
The trick is that the gear on the spindle turns as it engages the helix on the crank, so if you align it as it should end up (key pointing like 11:25 as you look down the shaft), it will be wrong when engaged.
You have to guess, install, crawl out from under and inspect, the (most likely) do it again. And again.
And again.
Keep trying and maybe you'll get it right.

After I get that set, THEN we'll see what the coil does.

 

No need to mess with all that. Just rewire the cap. Find TDC compression stroke, align the timing marks at the pulley, remove distributor cap and make visual mark of where the rotor is pointing. Re-install the cap and rotate the distributor until one of the spark plug wire bosses lines up with the visual mark.

This is now your number one spark plug. Go around the cap in the firing order (proper direction, of course) and you're done. You should get some hits and then some playing with the distributor, get it to run.

There's a couple of tricks one can use to find TDC comp stroke on number one without pulling the valve cover. Remove the coil wire and the #1 spark plug. Have someone "bump" the starter with the key while you have your thumb (or any finger) over the plug hole until you feel a blast. Rotate the engine in the proper direction until the timing marks on the pulley line up.

If you're by yourself, put a wad of paper towel in the plug whole. One has to be careful and design such a wad so it will be impossible to be sucked in the motor on intake but blows out on compression. Not really all that hard but one should never under estimate what could go wrong.

 

Like that wasn't my first option.
Unfortunately, the wire setup is so custom and closely fit that there's no extra length to repin the cap in the 180° "off" position. We have just a bit more freeplay than the adjustment slot allows and that's it.
Didn't stop me from trying though.

Finally resigned to the real task, I gave it the old college try- which we are defining today as "twelve attempts". Best I could do was one tooth off (although I really tried to convince myself it could be right, I knew it wasn't). Much easier with two people if the engine is in place, almost trivial if the engine is on a stand.

But I figured one tooth off was close enough to tell me something and indeed it was.
She allllmoooost ran.
At least made appropriate noises...and no obvious bad ones.

S. and wife are in CA house hunting this weekend and don't return till late Sun., so I don't know when next we can meet up, but when we do we're only about an hour away from a real test.

Fingers crossed, cautiously optimistic.

 

S. says he won't have any time this week and next Saturday he wants to work on the TT (which he wants to prep for sale), so if the Z is going to run anytime soon, it's up to me.
Accordingly, I go back today and continue trying to fit the drive spindle solo.

This time the whole swaybar comes off, so the oil pump (with spindle attached) can be offered up without having to weasel around the bar.
Here's why it's so difficult to do alone...
The gear on the spindle meshes with a helical gear on the crank. Align the spindle as you'd like it to end up, then move it one tooth and hope that as it meshes with the crank gear, it goes back to the desired alignment.
Hint: it usually doesn't.

If someone is looking from the top, they can see see immediately how it's going and tell you which way it's off. Working alone, you stuff it up there, screw in a bolt to hold it, crawl out from under the car and look. Then go back and do it again, trying to remember that what you saw above is reversed as you look now from below.

I've probably just developed a fixation about the difficulty...most would find this rather routine, I've let it get to me.
Time to sack up and just keep repeating until I luck out (the "Blind Squirrel" theory of success) OR I can try a method I read about last night that seems like it offers a glimmer of hope.

I'll try the latter first but will revert to the former if necessary.

 

i was working on my friends 20B the other day, i'm installing an ECU, so i decided to check the timing, and i put the crank on the mark, and then tried to get the CAS tooth to line up to the hole in the cover, and %*%^&$ it just didn't want to, or the CAS ends up more off centre in the Cosmo than the FC...

anyways i feel your pain!

 

Put up a CL ad asking for help and offer to share a bowl while they're there. I'm sure you'll get 20+ emails.

 

I realize that right after "What happened to Lady Mary on last night's Downton Abbey?" this forums biggest question is "I wonder if that stupid Datsun ever started?" and I'm here to alleviate your anxiety...yes, yes it did.

She will now reliably fire up, won't hold idle but revs like a sumbitch.
Lots of black smoke.

I've mastered the art of inserting the drive spindle, so if anyone has an L-series engine and needs the timing chain set up, LMK.

Sigfrid, having turned into Grumpy Cat, doesn't see much difference but I'm very encouraged.
Mainly because it now responds to component adjustment...spin the dizzy and it changes, rotate the TPS and it changes...it's like an almost real car.

I delegated the problem to my subconscious last night and this morning it delivered a plausible theory...what if S. screwed up 15 months ago and ordered turbo injectors? That would account for the monstrously rich idle.

We'll check it out.

 

I lives

 

Its Alive !

 

And we're happy for you both.

 

Congratulations!







I knew you could do it.

 

Define "it" loosely enough and i'll agree.

I'm disgusted that my bar has been set so low...big deal, I got a stone age simple engine to fire.
Still doesn't "run" by any acceptable definition and I'm not sure how to proceed.

Working alone and with an engine that hardly runs, I've been unable to check timing with a light and spark with the tester but I'm fairly sure the timing is correct and spark is good. Will confirm when help is available.

Spinning the dizzy now makes a noticeable difference, so that's encouraging.

Unplugging the thermosensor or the AFM makes no difference at all.
I can't tell if adjusting the TPS changes anything or not, I don't really think so.

Swapping ECUs changes nothing.

I'm ignoring the thermosensor for now because it's new and there's no adjustment possible, it is what it is.
If I could get either the TPS or the AFM active, maybe I could narrow down the problem but with both seemingly dead, I'm stumped.

We got another AFM with the "new" engine but it's larger bore and the wiring is slightly different, I'm not sure if it's stock '82 OEM or just some random part he threw in. I also have the RX7 S5 AFM which I've wanted to try since Day One but it'd really make sense to get the car running well first on original stuff and then swap in the Mazda part.

Until I can formulate a plan of attack, I'm lost.

 

Lol, I wasn't too far off about the dizzy being off.

Assume everything S did was incorrect. LOL no offense to him though (in case he's reading lol). It's easy to assume things only go on one way. Especially when you're rushing.

Remember, just like on the FC's, some adjustments (TPS, idle, timing, etc.) cannot be made (or the computer doesn't give a ****) unless the engine is warm, under a certain RPM, check connector set, and whatnot.

1. Double check your spark plug wire order on the dizzy and that they go to the right cylinder. Like I said, anything is possible.
2. Check the wiring to the injectors, make sure the wiring diagram and colors go to the right cylinder (not sure if this is applicable).
3. You seriously have no one that can start the car and give a lil' gas (which you can do from under hood anyways) or give you a hand? Not even someone not mechanically inclined? Damn.

GL.

 

Nope, spot on, you were.

We've both assumed our work was bad and have checked multiple times.

Yeah, our ECU ain't that smart, this is a much cruder system.
For instance, our TPS is not a potentiometer like the FC's, it's two contact switches.
One is closed when the throttle plate is closed, the other closes when the throttle is @60% open...so the ECU knows when the gas is off and when it's almost wide open and I assume it just makes **** up in the middle.
The AFM is a dead ringer for the S4 flapper door unit.
There is no O2 sensor.
The only "diagnostic port" in the stock harness allows you to bypass the safety switch in the AFM and run the fuel pump with the engine off. You could open the flapper door manually and achieve the same thing, so YAY!, I guess.

Yes, checked multiple times. In fact, during my last round I ohmed the wires all the way through the distributor cap, measuring at the inside posts. Firing order is 1-5-3-6-2-4, counterclockwise and is forever branded in my memory. Till next week, at least.
We have pinged the engine harness four different times. There are only like 25 wires in all and we are both certain that from end connector to ECU connector, it's all as it should be. We have +12v where we should and we have ground where we should.

Yeah, I'm just being a crybaby.

I have a question...
How does a car (like the S4) behave when the dropping resistors are bad?
The FC is the first FI car I've ever owned and being a S5, it doesn't have 'em, so I've no experience.
I never even much looked at the unit, it's pretty beefy pair of ceramic blocky looking things with two plugs. Don't recall even seeing much about it in the Z manual but there must be some sort of test regime.

I'm grabbing at straws here, we've been over everything else so many times and the resistors are virgin territory.

 

the injector resistors? car runs bad, or not at all

 

We fit the criteria.

I found the "spec" on the resistor packs (6 ohms resistance between the power in and power out pins) and will test it today.
Not sure if I hope that's it or not.

Apparently they are NLA from Nissan and used ones are kinda pricey (quick ebay search shows @$85).
There must be other cars that used similar systems and would have a usable option.

 

Like you said, the FC uses them. Don't know the spec. (ohm), but may be very similar.

An FC I once fixed with my cousin (bought to fix and sell) ran terrible and was extremely difficult to start. When it did, it smoked like a bitch and looked like it ran on one rotor. The owner was sure it had blown, but I disagreed, even checked compression in front of him. It was low, but I told him it was prolly ok. Still sold it to us, I guess he was done with it. Went over everything multiple times. I was a noob and even though we removed the upper intake many times, I never checked for 12V at the injectors. Finally checked the resistor block and one of the resistors going to a primary injector was bad. Swapped from my FC to the other one and car started! There was so much smoke, the neighbor thought there was a fire in our backyard! That was the second time we filled an area with smoke (different place). I guess it's an RX-7 thing.

 

It depends how they fail;
- If they short internally, then you'll effectively be opening the injectors more quickly and probably for longer (so you'll run rich), but you'll burn out either the injectors or the injector drivers in the ECU fairly quickly (at least under any load - idle you may be ok since the duty cycle will be low).
- If they become open internally, then the injector just won't fire - no chance of damaging anything.
- If they increase in resistance but don't completely fail, the injector may or may not open, and if it does open, it will be much slower and not inject nearly enough fuel, causing the engine (or at least some cylinders to go lean or just not run.

 

While screwing with the injectors/rail last week, I did a voltage test and saw battery voltage on all six connectors.
It wasn't till later that I wondered how that could be if there is a resistor pack in there, seems like it should be less, eh?

Off to check in a little while.