milk passed through my nose in laughter.

 

That would be especially impressive if you weren't drinking milk at the time.

 

Day Three:
Drove up to Boulder this morning (early this morning) and attended a Cars & Coffee with spectre.
I was amazed by the range/diversity of cars, there was something there for just about anyone.
I had no idea there were so many new Astins, Ferraris, Lambos and Lotii around.
Multiple Vipers, Corvettes and Porches.
Then, the weird stuff...even a (new) Morgan three wheel.

And our two, sad looking rotaries.
Represent!

Anyway, it was fun.

Besides the first three minutes of the mornings first start, there was no indication of the throttle body mods. The car drives absolutely as normal, no lurching, hunting, backfiring...nuttin.
The warm weather lessens the urgency, but I'm pretty sure some sort of cold start control will be implemented...I'll start with a cable and go from there.
Even if I put the thermowax back in (which I'm not totally averse to) I see no reason for the rest of the stuff (secondaries/throttle delay valve) to return. I can't tell they're missing and would need serious convincing they're useful in order to reinstall them.
**** on a boar kinda thing.

 

Questions, questions, questions...

-Despite thermowax and AWS valve delete, the ECU still tries to initiate the bloodcurdling superfast 17 second idle if the car is in neutral. It can't actually reach 3k rpm (because the thermowax is not already opening the throttle) but it tries using the BAC and can manage about 2k rpm...still unacceptable.
If the trans is in gear, this strategy is disabled, just as stock.

-It appears that the neutral switch on the trans is ONLY used for this one function (remember, this is not the same as the clutch switch for the starting circuit) as I cannot find it referenced in any other scenario save for cold start accel.
Is this so?

-My read of the schematic indicates that the neutral switch is basically a make/break contact that sends 12v to the ECU when the car is in gear.
Jumpering the connector after bypassing the switch would tell the ECU the car is always in gear and defeat the AWS routine no matter the state of the trans.

At least it seems like that is how it would work.
What, if anything, am I missing here?

At cold start this morning I had the car in gear and thus bypassed the AWS sequence. Idle was a nice solid 1200 rpm, just what it's supposed to be as the thermosensor warms up (to 160°?).
She dies under decel for about the first mile of driving and thereafter is fine...a nice steady 750 rpm is possible after about two miles.
I could see getting used to this slightly primitive behavior during warm months but think it will be tiresome when real cold returns and so I plan to address it soon.

Otherwise, all seems well.

 

Damn rotory's, oil temp matters more than water temp.

 

Maybe I should reroute an oil line through the thermowax then?

Ha, ha...no.

Been playing with a thermowax (parts from two bodies are still scattered all over my desk and thus, immediately within my highly distracted view) and may be reconsidering my approach.
As I pondered the wax unit I was wondering what that little water channel in the carb body is supposed to be doing. If you are unfamiliar with the finer details...there is a small(ish) hole in the mounting flange of the thermowax that flows water to a @1" long dead end groove cast in the throttle body.
In all three of my throttle bodies this channel was half full of dried powder/grit, I have no idea what is supposed to be happening but it surely has to be more than a "crap trap" for the coolant. It couldn't possibly be a means of heating the body but I see no other concept that might apply.
Any ideas?

I decided that if the thermowax was reused, that passage should be plugged, so that's what I did. Machined a bit of aluminum to a nice press fit, goobered it with some JBweld and pressed it in.
So I hope it didn't do anything important.

If it seems like I've turned 180° from yesterday's "cable is bestest!" attitude, well, that is partially true.
I was intrigued to the point that I tested both units (one is the nice one, one the backup) and they both work exactly the way the manual says they should, the extend/retract is just as advertised.
I admit a grudging respect for such an apparently primitive device that has functioned all these years (I've never had cold start/idle issues) and it does have the advantage of already being in hand and easily used.

I keep looking at the inlet and outlet water ports- the water lines being my biggest objection (mostly aesthetic)- and am considering options to change them. Or I may just go back to the stock lines for now and worry about the hoses in a few months when I do the injectors.

For the time being I'm just cleaning up the #1 throttle body (the point that initiated this whole kerfuffle). The secondary plates/shaft/damper have already been removed along with the main throttle delay.
BTW, removing just the main delay module and its bracket makes it possible to remove/install the body without loosening the dynamic chamber so the body clears the secondary fuel rail. If you have a S5 and have removed the throttle body, you know of what I speak.
I think that delay is useless anyway and would recommend ditching it just on general principles.

And that's what I did today.

 

I was saying they don't act like they're "warm" until the oil gets warm. Pistons seem to do much better with only warm coolant. No dissing... chill man.

 

Sorry, no offense intended...I lacked context to your reply.

 

Post some photos of the groove and such you're curious about. I haven't taken mine apart, and as we have both learned lately, there are more differences than similarities across the two half-generations' intakes.

 

Here you go:


The thermowax is sitting atop the throttle body here, flange facing us.
On the thermowax you can see the impression of the channel and the passage plug I made.
The channel itself is on the body, there is no outlet or passage beyond what you see. Coolant goes in and then...well, looks like it just sits there or something, I really can't tell.

The rather large hole in the body next to the groove is one of the holes the secondary throttle shaft used to fill. On this side the hole gets covered by the thermowax flange but I've already drilled and tapped it for a plug, like the other side. Most writeups use a 1/8 NPT pipe plug for this but I was contrary and used 12mm x 1.5 plugs, screwed in with a healthy smear of JB weld on the threads.
It'll all be dry tomorrow and I may put it on then.

 

Re: the groove. some of the other years have the second hose nipple in the throttle body, so the groove is used to go from the thermowax body, into the TB and then out. i wanna say the turbo's are like this, and the FD as well. on yours it looks like **** on a boar.

Re: thermowax. its lone job is to push the throttle plate open when the engine is cold, i personally find this nice. it is adjustable for how long (coolant temp) and how many rpms it does. so you can adjust it so it does fewer rpms, and pops off sooner. i like it to do about 1200, as i have a stoplight, so its always odd to be sitting at a stop light (forever!) with the engine uselessly doing ~2,000rpm....

Re: AWS. this is the useless one. i know the ecu looks at coolant temp, which has to be in a certain range, and if the car is in neutral, however i think i would just plug the AWS hose with something and be done with it. possible it may want a small hole in the plug, as the ecu does add fuel with AWS.

Re: secondary throttle plate. in the NA and FD, these just open when the coolant temp hits, i think about 80c. something newer cars do with software. if you don't beat on the car when its cold, you'd never know these are even there. its a system for muggles.

 

The AWS solenoid is gone and the port in the dynamic chamber capped.
I did this so long ago that I incorrectly told spectre the leftover connector was a diag plug...I had completely forgotten the solenoid even existed.
Even with the hardware deleted, the ECU seems to attempt a higher idle for the beginning of the start sequence before settling to @1200 rpm. Put it in gear and this does not happen.

I still haven't found any other circumstance in which the ECU utilizes the info that the car is in gear. It seems the cold start is the only time this matters.
Tomorrow I think I'll try this body/thermowax and at the same time, jumper the neutral switch and see what happens.

 

Makes you feel better, my aws randomly works. Something you are helping me figure out through this adventure.

 

Well, the "adventure" stumbles forward.

Put the thermowax on and adjusted the cold setting (77° ambient temp) as per the FSM.
Then poured boiling in the wax (and over the body too) and watched as the plunger extended and the cam moved.
But it did not move far enough for the cam to fall off the roller and in order to make it do so I had to remove the spring from the adjusting screw to get enough adjustment on the cam.

This indicates to me that the wax is expanding, but not far enough. Unfortunately I cannot find a spec that shows plunger movement (min>max), if anyone knows where this is, please enlighten me.
Right now, mine moves approximately 1/8- 3/16" from full cold to full hot.

I could still use this- even with reduced plunger stroke- but I need to get the spring back on the adjusting screw (spring tension holds the adjustment screw from randomly spinning out of spec).
I could make up a spacer/cap to glue on the end of the plunger, which would bring the screw back into the normal adjustment range...but before I do I'd like to know that's my only option.

TBH, at this point I still have no clue how the thermowax pellet works on a mechanical level, so I think I'll tear my spare unit apart...it appears that removing two more screws and a retaining strap allows the wax section to slide out of the body and maybe something will be revealed (like heavy corrosion on the part that is in contact with coolant, inhibiting heat transfer).

I'll go do that right now.

 

Adding a spacer would be the equivalent of adding adjustment, not travel. You'll be able to get your high RPM to spec out, but only if the low spec has enough clearance. I haven't torn into this particular system yet either, but that may be cutting off your nose.

 

My, that was easy:


We see the thermowax pellet, the body of the assembly and the retaining bracket.
The brass half with the o-ring is what slides up in the body and is exposed to coolant.
The steel end is the plunger that you see when it's all together.
I chucked the pellet in the lathe and briefly cleaned it up with a scotchbright pad but it wasn't that corroded to begin with, so I doubt that makes much difference.

Measured the length of the exposed plunger at room temp, then dropped the pellet into a pot of boiling water, let it marinate a bit, then measured the plunger at full extension.
Dropped into a bowl of ice water and repeated the process.

Both times the measured plunger movement was .150", so, just a bit over 1/8".
This corresponds closely with the other (installed) unit and I'm thinking this is close to original spec.
If so though, I'm wondering why the adjustment screw is too short when used with the spring.
The spring coil binds before I can get the screw far enough to release the cam.

As I ponder that silliness (I mean seriously, has anyone else delved so deeply into this obscure mechanism?) I had another weird idea to mod the unit even further.

Visible in the pic is the large tapped hole left after deleting the vacuum thermoswitch (for the secondaries). This would normally just be plugged but could easily be adapted into the water inlet.
I could position the bung to any orientation that made the hose routing more logical and then pull the original water fitting out of the housing and drill/tap the resulting hole for a plug.
This plug could be used as an air bleed for the coolant loop (which is the highest point in the system, remember).

What the hell am I getting into?

 

you're a step ahead of me! i usually just clean it out, and adjust to my taste, i do want to stick it in boiling water, i just haven't.

i did round up all the thermostats at one point and have a cook off though, i actually learned two things.

1. my brother doesn't like rust in his oatmeal
2. the spec for the thermostat is the minimum, a new one will open about 2x the spec.

 

I"m rubbing my head and face in like a headache/thought. I'll be perfectly honest, I've never fucked with the thing. I always imagined it worked like the old by-metal choke springs in old carburetors. Applying pressure so that when one steps on the gas pedal to start, it causes the stop to jump a step on the fast idle cam.

I don't know man, fill us all in when you find out.

 

Tomorrow I pick up a chunk of aluminum rod so the thermowax mod can continue.
Meanwhile, my attention wandered back to a concept I've had for years and have explored a few times, but not very seriously.

When I formulate an idea and begin to explore feasibility, the first thing I look for is the "dealbreaker"...the part that's too complicated for me to make, too expensive to buy or just won't fit.
For this particular concept, this is the part I needed to change:


I've pondered a number of ways to achieve what I want and have had this spare elbow for a few years but just never felt comfortable enough to begin.
In truth, most of my ideas involved starting from scratch, this original part was just a convenient way to get a template for the flange(s).
But, as I am wont to do, the part hung around my desk and I'd muse upon it fitfully and with little intent.
Until yesterday morning, when I woke up with a fully formed plan of attack and the curiosity to actually execute it.
After years of dreaming, the work took under an hour and turned out better than I'd hoped.


It's glued/clamped now, so no more shots for a while.

I've done a crude test fit (duct tape was involved) to make sure nothing egregiously wrong was going to happen and then mapped out a non-invasive first iteration of the idea, just as a proof of concept.
It's fitting that "Proof of Concept" and "Piece of Crap" are interchangeable acronyms...this little project could be either (or potentially, both at the same time).

I will admit/stipulate up front that this whole idea is purely aesthetic and has no technical reasoning behind it at all. It is fulfilling a vision I have of the engine bay if the Mazda guys could have worked without all the production constraints (like, no AC/PS, no mechanical fan, etc.).

Tomorrow morning the part will be dry and we'll go from there.
I meet spectre at the junkyard in the morning, so probably won't get much done till later, maybe even Sunday.

It could be amusing.

 

OK, so here's what the two above pieces turned into:




About those bungs...
I've always been leery of the stock setup, there is no effort made to cram air into those bungs, so I suspected that the devices at the other end (BAC and ?) sucked what they needed.
But would they benefit from a bit of crammage?
This arrangement is the simplest way to get me started but easily modified if there's a problem I can reasonably attribute to turbulence from the bungs.
We'll see.

Spectre and I met at my junkyard today and during our ramblings I found the sweetest rubber boot to join the AFM to this new adaptor.
When you pop it all together, you get the Leaning Tower Of (Questionable) Airflow:


Tomorrow I'll put the trusty K&N on and see what she thinks.

Depending on how that goes, Stage Two will commence or she'll go back the way she's (happily) been.
Here at Casa Clokker we're cautiously optimistic.

 

Sweet new bong

 

If all else fails...

 

well the BAC is closed at idle, and the other is for AWS?

 

I've got to figure out what that second hose is doing, because I have no idea and cannot see where it goes once it slithers beneath the exten. manifold. I have no AWS solenoid and the bung on the back of the dynamic chamber is capped but that hose is a massive vacuum leak when the engine is running, so it's clearly connected to something.

I'll be forced to figure it out soon because I'm terribly unhappy with the way the hoses currently connect to the modified adaptor.
There were physical constraints as to where I could locate the bungs and they are not ideally placed for hose routing. I think my next step is to plug the holes I made and fab up a 1" spacer plate to go between the throttle body and the adaptor. I could put the bungs anywhere I pleased that way.
Tomorrow I'll see if I can hunt up some material to work with.

But that's for tomorrow and naturally, I was anxious to see what she'd do right now.
I refit the primary (the "good one") throttle body and the stock thermowax (haven't modified the other one yet). I'd gone through all the adjustments and was curious if I'd done it right.
The throttle body swap meant that the TPS was moved and probably now out of adjustment.

Finally assembled, she looks like so:




A bowl for good luck (and to deaden the pain if she exploded in my face) and it was time to find out what would happen.
Expectations ranged from, at worst, fiery death! to ideally, run well enough to tune.

And she ran more or less perfectly.
Took a test drive to warm up and reset the TPS (it was 1.03v instead of 1.00v), adjusted the idle down a bit and took off again.
On the highway this time, pulled clean through 7k rpm...several times.

Back home, recheck TPS (was fine) and fiddled a bit more with the air bypass screw.
Warm idle is very good, we'll see how cold start/idle is again later tonight or tomorrow morning. I'm expecting it to be fine.

It's working better than I'd hoped so far.

 

Nice. Least someone in the community had a good day. After I fixed some things, the car got jealous I applied wax to the jetta and **** the battery out on me.... on the driveway... on the hilly part..... twice.