The pictures (and install) are deceptive and not really what it will look like when done.

We trimmed the two side pieces to fit the lights and just slapped the kidney center on top but the next step is to trim the inside edges of the sides to match the center, so it can sit more flush with the rest. It will stand a bit proud but not as exaggerated as it is now.

Z's are traditionally seen with horizontal slats because the bumper imposes a strong horizontal element that must be worked with.
Delete the bumper and other elements can be accentuated, in this case, the hood bulge.
The color mismatches mask the effect but that kidney center perfectly carries the visual flow of the bulge down the nose opening and breaks up the large, rather ungainly opening left after the bumper is gone.

Typically however, we redo things like this several times before getting what we want and I suspect the final grill treatment will be completely different.
It's a process.

I'm guessing that I'll get the car running better this weekend.
We've both been reading forums and coming up with "easy" fixes...stuff that's relatively cheap to try as we're not sinking a lot more money into this pig engine.
If we can get her rolling with this motor, that's great but it was never the longterm solution. A swap was always the final plan, the question was when it would happen.

One thing I'll be trying is a Maxima coil transplant, it's supposedly a very good unit and we have no idea how suitable this chrome POS we currently run is to our ignition.
Also on the way is a new thermosensor which pretty much tops every list as a possible culprit.
Bear in mind that the Z has no O2 sensor, it's only input is water and intake air temp, so good data from the thermosensor is very important. Apparently, the usual failure mode defaults to always reading "cold", which would explain why we're so rich.

Easy enough to try.

 

Haha, car probably thinks it's -70*F. Never knew why sensors on a vehicle would have such ridiculous ranges... in case you try and drive it on the moon?

 

lol yeah and the older ecu's don't second guess anything either, if the sensor signal is -70, it fuels for -70! and some of these older ECU's are setup so that the temp sensor has a LOT of authority.

the example we know about is the E30 BMW, is setup so even at WOT and redline it has enough left over injector duty to apply the full -20c enrichment. so at normal temps, the injectors peak out at a low duty cycle... i suspect the S4 is like this too

for diagnostic purposes you can use a potentiometer to take the place of the ECT...

 

Well, the new sensor is $13 and on the way, so my "diagnostic" will consist of screwing in the new part and seeing what happens.

S. has been reading up on the AFM and apparently, if you can remove the cover (which is epoxied on), there are adjustments available inside.
I'm not sure but he's excited about it.

With the battery recharged, he says it starts easier every time and seems to be running better...all with the AFM unplugged. He seems to think the ECU is "learning" but I'm pretty sure it's too dumb to be doing any adapting.

So, the situation is still rather fluid, no real indication of where to go.

 

We've both been reading up and collecting ideas for me to try this weekend.
Not sure what Sigfrid is thinking but I'm pretty certain that our coil/distributor are not playing nice together because we have a pathetic spark. Our plugs are black/sooty/fouled with hardly any run time and that's obviously not good.

Oddly, Sigfrid says she's getting easier to start and no longer bogs off idle and in fact, might actually be driveable.
This makes no sense to me.

It makes no difference if the AFM is plugged in or not.
Twisting the distributor from one extreme to the other makes no difference.
The TPS will prevent her from starting if maladjusted but fine tuning it also makes no difference.
NONE of the normal adjustments do anything but the car continues to run and according to S., she's running better all the time.
If I could get just one of those components working properly, I think we'd be on the right path.

 

I hate to be "that guy" but maybe the hastily thrown together engine isnt that bad and just needs some breaking in?

When I was in college for automotive, we would rebuild Toyota and GM motors all the time. Usually during the rebuild you want to have the cylinders bored to get rid of any piston step wear. Obviously, this is school and we never really bored them out, just honed them and clearanced everything to spec. They would run like absolute **** for a while until the new rings got seated and everything broke into the step wear.

The cars we got that got "grannied" Where the freaking worst. You could take your finger nail and catch the step wear. The granny engines we never rebuilt, they where just used as a warning that you never ever ever just baby an engine.

 

couple of thoughts.

1. i also am skeptical of any learning, the Japanese typically don't have this in their ECU's until the mid 90's, and even then

2. it is possible with the idle switch on, that timing is a fixed value, and the AFM is ignored...

 

You know, as much as people bitch about the USPS, my experience has been overwhelmingly positive. Sigfrid placed a Rock Auto order Monday morning, we had shipping info by that afternoon...one package on Friday, another on Monday.
Both arrived today.

The pisser about their efficiency is that I was at the garage today taking care of a few odds and ends, getting ready for my housesitting weekend and as I left, I saw the mailman down the street.
Never even occurred to me the parts I was awaiting were only yards away as I rolled out of the driveway.
Oh well.

We have a new distributor cap/rotor, thermosensor, Miata water temp gauge sensor and at long last, a gas tank cap.
None of it will probably make much difference, I fear.
The gas cap and new wiper blades will be useful but I'm thinking this motor is junk.

It's going to be quite fall-like here the next few days (high in the low 50's on Friday), so I'll put in the new stuff and see if I can get any comprehensible results this weekend.
Without significant progress, I say we stop the engine work, finish off the body and get the interior at least as far as carpet while we still have decent weather.

Figure out what we want to do.

 

OK, started my last major push on the engine.
New dizzy rotor/cap installed, along with the new ECU thermosensor.

Reworked the front of the engine harness, it's better and it's done.
Turns out there's supposed to be a dedicated ground strap for the distributor housing...seems redundant but I made one up anyway.

She fired right up and after a few minutes, idled and revved fine.
And, for the first time in my experience, she actually responds to spinning the distributor.
The stock AFM is in place and connected.

Just sitting in the garage, she runs like a champ.
No idea what happens under load though and before actually finding out there are a few more things I want to do.

The fuel pressure gauge ( a cheap POS that came with the Chinese eBay regulator) has either failed, is blocked (somehow) or we actually are running on zero fuel pressure.
The latter seems unlikely.

It is conceivable that there is a problem with fuel delivery, the first step is to install a filter between the tank and the external pump and then do a flow test.
We're using the original fuel pump and I think it works fine but no sense not testing and ruling it out.

I'm semi-optimistic that we're finally within tuning parameters and our adjustments might start to make sense but before she runs again I need to get the alternator feedback loop (warning light) hooked up so it's not overcharging.

I've been reading widely about our problems and came across this little nugget of weirdness...

Supposedly, in a properly set up FI Z, removing the oil fill cap while running will kill the engine because you've just introduced a giant vacuum leak.
If the car doesn't die, it means you have intake leaks that you've tuned around and need to find/fix.

I can't wait to try that out.

Amazingly, she has not leaked a drop of oil, water or gas...so that's nice.

 

It's the cam timing.
Three teeth off.

It's a miracle she ran at all.

So now the question is, was this a bunch of good parts hastily thrown together so there'd be a motor in for the sale, or is it a collection of crap hastily thrown together so there'd be a motor in for the sale?

A timing chain kit (sprockets, chain, guides, gaskets and tensioner) is only $80 and would take but a few hours to install. Sigfrid seems to think he can do it without stripping down the front of the engine, claiming he's done it several times to his Evo but I'm dubious.
At any rate, it needs to be fixed.

 

Spend $80 and put S to work then. You should put a wager on it for fun though, if he strips down the front of the engine, you'll win.

 

Well, here's the thinking so far...

If Sigfrid can actually do it, fine. We slap on the valve cover and see what happens.
But I don't think it can be done because there's no way to externally release the tensioner.

Assuming failure, we then strip the front of the engine down...probably a two hour job (have to pull the radiator and hood to gain access). The water and oil pumps must come off (they're both external), as well as the crank pulley and then you're there.
Normally, this would be a no brainer...you'd order up all new parts/gaskets and just R&R the whole shebang.

But what we'd do is open it up and try to divine the state of the deeper internals from what we see, decide how much further we want to go with this particular unit.

We are, as usual, in SNAFU mode.

 

After much back and forth, Sigfrid and I agreed it was both too risky and not informative enough to try the quik-n-dirty timing change, so today I head over and strip down the front of the engine.

Apparently, the cam sprocket can be moved without further disassembly but you have to make a wooden wedge to hold the tensioner in place and even then it seems about 50% of them fall out anyway and drop into the oil pan.
So, there's that.

And we want to see what the water pump looks like as well as the chain guides, maybe get a better idea of the internal condition.

There are three ways the cam sprocket can be installed, depending on how tight the chain is.
When you have to use position #3, you know the chain is at it's limits and needs to be renewed.
We are currently three teeth beyond this last slot, which means either the chain is stretched beyond spec (by a LOT!) or they simply didn't even try to get it on right.
I should know by noon.

I went to the yard yesterday and got distracted into thinking about my own car (for a change).
I was looking at a 2004 Mazda6 and was struck by how similar the gauge cluster was to the FC's...and my weakness for silly cluster swaps is well documented, so...

This is my first run in with a computer controlled cluster, I'm not sure if I can do anything with it but it's an interesting piece to play with.
I've spent but a little time on it so far and haven't even gotten it all the way apart yet.

The back of the housing has a white translucent cover held with a screw and some clips, it pops off to reveal a hard circuitboard. There are no bulb sockets, so I'm assuming all the lighting is permanently installed LEDs on the other side of the board.
The housing is less than an inch deep, no where near enough room for a regular gauge mechanism, so I expect to see just some sort of needle drive setup instead of normal gauge guts.

And yes, it is very close to the FC cluster shape, much closer than the Miata unit I adapted in before.
It would look bitchin.

 

the only timing chain car i've ever done was an early 80's B2000 pickup, and Mazda was nice enough that they had a little door in the timing cover to release the tensioner without having to do much else.

i vote for #3, installed wrong.

i don't know about the 6, but the Rx8 is mostly driven by the ecu, through a CAN network, which i guess you could either simulate, or plug enough stuff into a stock ecu to get it to run the gauges.

the Rx8 is all LED's, so i'd expect the 6 to be as well.

or, i wonder if you could put the guts from the FC gauges into the 6 cluster?

 

It's probably canbus, so you will need something to convert your FC's analog signals to canbus. I'm not sure if you can buy something off the shelf for this, but I have seen arduino's being used for this. The hardware part of it all is pretty easy, but programming it to work can get tricky. You need to find out what sort of canbus messages the instrument cluster likes to see. More info about the subject here:

https://www.cantanko.com/rx-8/revers...ster-part-one/

 

Yeah, none of that canbus or emulating nonsense will be happening.
Once you get beyond "think of electrics as pipes and valves" I go on the fritz.
But I'm flattered y'all actually chimed in with responses that assumed I know more than I do.

Engine front stripped down, even futzing around it only took about an hour and a half.
I can't tell if the PO screwed up the chain/sprockets or didn't even try, but it's way off.
Sigfrid is going to evaluate the sitch tonight, see if he can get it right.
Assuming the chain isn't too stretched and he's successful, I'll go back tomorrow and button it up.

A lot will depend on the next few days...

 

Plans if the engine is toast? A moment of silence, surely, but did potential alternate drive-train swaps ever come to fruition?

 

As yet, no potential swaps are in sight as Sigfrid seems more focused on getting this engine running.
We've kinda latched on to the timing as the root of all our issues and hope we're good to go.
Find out later today how lucky we are.

Here are some pics you rarely see on this forum:




This shows the timing chain/sprockets in the correct position, they were wildly off before.
Today I clean everything up, slather it with RightStuff and bolt it back together.
Absent any unforeseen disasters, she should run this afternoon.

 

interesting to see the timing chain guide is similar to the KA series engine from Nissan. The plastic always wore out over time and typically grenades itself in the timing cover assembly

 

The current plan is to slam this together and see what happens.
Depending on the results, the path of least resistance would be to find a reconditioned head, order up new timing components and run what we brung for the time being.

Before winter sets in we need to get the final coat of dip on and at least the underpinnings of the interior (sound deadening/carpet) in place.
As long as the engine runs and the car is moveable, we can ponder options without too much pressure. If she's still dead in the water, I'm not sure what we do.

 

Interesting to see that old motor in as clean as it is, I have to wonder along with you, did someone hastily put it together for a motor to be in the car to help sell it

 

You had to pull the oil pan off I am guessing to get the timing cover off.

I'd check the torque of the main bearing cap bolts along with the torque on the rod end bolts while it's off. That would be a good indicator whether or not someone just threw a bunch of **** together.

If I need to check torque on something that has already been torqued, I always set my torque wrench to 95% of the specified torque and see if I get the magic click. I do this because not all torque wrenches are equal and it is usually better to be slightly under torque than over torque.

 

No, thank Jeebus, you don't.

Car still runs like poop though.
The only other thing we can think to do is find a known good ECU, see if that's the problem.

Believe it or not, the poor performance is not my biggest problem though.

Sigfrid is moving to California.
He leaves mid-November, the family follows in June after the school year.

I have no idea what happens to the car project, how that works, what he plans.

Kinda numb right now, not only losing a good friend but also a car I've poured my heart into and will not see finished.
Damn it.

 

relish in the good times had brother. Time to start tinkering on the FC again.

 

I did just buy a gauge cluster...