I appreciate the help, but I'm not an electrical engineer so I have no idea what I'm doing. All I know is I have a sync-loss problem and nothing more.

Yes, me and GraemeD.

The three of us can't be the only people running MS2 w/VVTuner.

Should I call DIY and ask about this or am I barred from support due to not using MSpnp2? I'm about to get some help from someone on here with the soldering and if things go wrong and this is like a bad joke or something, I'm in trouble.

1) Remove the two resistors mentioned (R2 and R3)
2) Desolder white wire from pin 1 and solder it on white wire on pin 3
3) Desolder pink wire from pin 2 and solder it on pink wire on pin 4
4) Enjoy your car

Clearly, you are a straight-up-player.

This thread needs less boring wiring questions and more skanky [car] pictures.

*My computer wanted to correct skanky to swanky. Uh, no.

I have two photos, one is supposedly pre-modification and the other post-modification

Pre:
https://www.miataturbo.net/attachmen...ine=1351097411

Post:
https://www.miataturbo.net/attachmen...ine=1351097411

As you can see, R2 and R3 are already gone from the pre-mod, and Q2 and Q3 are gone from post-mod.

Also, I see no wires in the pre-mod picture that need to be desoldered, as mentioned in steps 2 and 3.

And frankly, I don't know where you are getting the pin number references.

Looks like the connection from one of the pins on the DB9 connector that goes to R2 is being taken to Q2, but since I'm guessing this is at least a double layer PCB, I can't follow all the traces.

Any further clarification would be appreciated, as I don't want Hustleberry crying if something adverse happens ;)

Like he would have to just unplug the VVTTuner for a bit until it is fixed?

I gave hustler some contact info with who he should talk to at DIY.

I won't cry, but if we do mess it up I'll give you a great deal on a VVT head.

Well, as I mentioned earlier, anything I do I can easily undo, but I'd rather make sure I do the right thing the first time.

I'm getting conflicting information that doesn't correspond with pictures and without a proper VVTuner PCB schematic, I'm a little in the dark.

Now you're playing with fire son ;)

You can have the head from my '91 if you want :rofl:

A board layout picture like this would be extremely helpful

I don't suppose anyone has one handy :rofl:

Attachment 239810

I emailed DIY but I feel Reverant has shown me the way.

This is something I really need to learn, I'm paralyzed without the basic skill.

If you mess up I can mail you a bottle of Stoli.

Ya, and I can do this for you quickly since you need the car, then teach you so you can do it on your own in the future

No worries Trey

Drinking and setting fire are nearnderthal type tasks which I can handle myself. I need you girls to help me with this fancy space-computer shit.

Oh, I get the reference now

lol that was funny (in an asinine, waste of money kinda way)

Do exactly as I said. Exactly.

If R2 and R3 are already removed, obviously omit that step.

If you look closely at the DB15 connector, the pins are labelled.

Looking at the connector on the VVTuner, pin #1 is on the top left. It has a white wire on it. Remove it from #1 and solder it on pin #3, which is also a white wire.

Do the same with the pink wire on pin #2. Remove it and solder it on #4.

Simple as that.

Ignore any other information you have seen, heard.

Ahhh, you're talking about the DB connector pins. Beautiful

That's really helpful

I get it now. We're taking two different input paths and changing it to one.

Awesome

Sign-in if you're writing in MSLabs for President, 2012.

Is this like "crossing streams"?

First Google Images result for "crossing streams"

https://www.miataturbo.net/attachmen...ine=1351104531

I assume your safe search was on?

those photos are from my VVTuner. it does not have any wires in it. the 15 pin connector is thru board mounted. the wire you see in the photo are the two jumpers I added. maybe there are two versions of the VVTuner? one thru board and one with wire/leads to the connector.

Sounds like there are two versions. Yours with the R/A through hole versus a straight one with solder cups

https://www.miataturbo.net/attachmen...ine=1351109501

Good to know I have the solution to both versions

Thanks again Graeme and Reverant

VVTuner uses a standard right angle, through hole boardmount D-sub. There is no VVTuner version that uses an internal solder cup connector.

The other question is why is VVTuner occasionally causing a sync problem with MS2 in pass-through mode? That I don't know. This would be the 3rd report of it. We've been unable to replicate the problem in either pass through or parallel mode with MS2. Kevin's 01 swapped 90 recently spent days on the dyno, running without sync loss.

We want to find or fix, but we can't find the problem.

Thank you Sir Ben

Why not make the adjustment that Graeme made for all? Is there a reason this won't work? Since I have the problem, I'm happy to help you track down the problem if possible. I'm an idiot though so that's unfortunate for both of us.

Because we haven't observed the problem, so I don't want to fix what I can't find to be broken. The only 3 reports of this problem are you, Graeme, and Reverent. I'm not dismissing this in any way, don't get me wrong, but I don't know why it's just you 3 guys on this forum? We sell lots of these things, with no other reports of issues.

Also, that fix relies on a parallel install with pullups in the other ECU, so it would actually break standalone functionality.

The only commonality I can find so far is it is 3 reports on 1 forum, and all 3 had MS2 based ECUs (though different versions). So that leaves me to believe that is related to MS2 and VVTuner, but our own car works brilliantly with this combo.

If there's a problem, we want to find it. I just need more. Is your ECU plug and play with a standard 1.6 harness? If so, we can put it on Kevin's car.

Nope, 1994 harness. Unfortunately I don't have a VVT head on my track car which is a 1991.

Thanks for looking into this.

Who installs a VVTuner stand-alone and why would anyone want to?

I don't have a 94 with VVT swap here unfortunately.

VVTuner is sometimes used on swapped cars running non-MegaSquirt management (including stock). Deleting the pullups from all boards would break that functionality as well as pass through functionality that works for everyone else.

Can you run VVTuner on a non-vvt OEM computer and get an increase in performance without destruction?

Yes.

:rly:

I sent 3 emails to DIY about this over several moons, many many moons ago and they never responded to any of them.

It would be interesting to see what my stock BP4W ecu + BP6D head + VVTuner would do. I haz a boomslang somewhere in the garage too, but I'm broke and see no VVTuner in my future :(

(Hustler: buy my vvt head!)

Yes. You leave some on the table compared to a standalone, but a NA6 with VVT swap, stock computer, and standalone VVTuner will make substantially more torque than stock. With the same swap but without VVTuner, you leave a huge amount of torque out of the mid end. A standalone can still mean 10+ ft lbs down low and 5+ hp up top (on a stock engine).

You may need to check the email address you are sending to, or perhaps your spam folder for the replies. We usually answers emails sent to websales@diyautotune.com the same business day they are sent. We get a huge volume of emails, so it would be possible for an email to slip through the cracks (nobody's perfect), but there's no way we missed 3.

Thanks Ben, but this was literally years ago so no worries. It wasn't until today that I even knew this would work with the stock ECU as your site does not explicitly state this.

Are you guys EVER going to offer the VVTuner as a kit, because I would definitely buy one. I'd also spend money on a PNP harness for a 99/00 ECU.

Like Hustler, I'm a moran and don't know how to take this:

https://www.miataturbo.net/attachmen...ine=1351127195

and magically splice it into this:

http://www.madracki.com/miata/images/wiring/00sys.pdf

without causing this:

https://www.miataturbo.net/attachmen...ine=1351127195

(Note: I haz correct boomslang and would pay one of you goobers to build an interface harness. PM me)

Fixed? We'll see tomorrow.

It was always the plan to offer VVTuner as an unassembled kit. However the assembly had a couple of aspects that we felt may be too awkward for some users, so we decided to offer assembled only.

Recently we respun the board. It's the same design, just a somewhat different layout and form factor. The new board is much easier to assemble, so we'll offer it as both assembled and unassembled kits in the future. That's coming, but I don't want to launch that before figuring out this other thing.

The sync issue is not related to the old layout or the new layout. Graeme had an old board and Reverant a new board. Not sure what Hustler has.

Well at least it still runs and I didn't burn your place down.

Ben,
Are you saying that you can run an NA6 or NA8 stock ECU from the VVTuner or are you still recommending to use the NA CAS for the ECU? That is what I wanted to do from the start, but I could not get it to work.

You should be able to use the VVTuner with with the stock 90-97 ECU. It has the option to convert the NB cam/crank signals to the same signals that a CAS outputs.

buy a boomslang.us patch harness and do it yourself, it would be hella easy. Or PM me.

Have you tried this yourself?

I personally never ran it that way. I was planning on it, but MS3X added VVT support before I got a chance to try. I know based on the documentation that it should be doable and should work.

Sync loss is still there. I will go even tighter on the CKP. Is there a chance these used sensors are bad and if so, how can I check that? I have two new sensors but those were resrved for the track car. Oh well, more god damned money.

Loosing crank or cam? The NB cam sensors are known unreliable, especially in the VVT head. Though I've so far never needed them, I keep a spare cam sensor in the glovebox of the street car and another one in the trailer for the track car.

Sync loss #32. I suppose I'll put the new sensors in and buy another round of spares from Mazdacomp.

What is funny is that I have never had an issue with NB sensors in the past 2 years with them actually working. I have used 3-4 different crank sensors during that time, all have been used. Mostly because I always forget to remove them when I am removing the crank pully bolt and I end up breaking the plastic mounting tab for the crank sensor.

Don't buy anything yet. Remove VVTuner, replace with dummy plug, run the car for a couple of day with the dummy plug. See if you get anything in those two days.

I'd love to do it myself. I can solder wires together and I can mount through hole components, I just have a hard time with wiring diagrams without really specific instructions. :hustler:

I'll stop crapping up Hustlers thread and start my own. With blackjack, and hookers, and stupid wiring diagram questions. ...or expect a PM

i could draw you an easy to follow picture. we are talking splicing 15 wires, and maybe cutting 2.

https://www.miataturbo.net/megasquir...nms-ecu-69111/

Let's do this thing!

Let me know if you want me to remove the two jumper wires and put the two transistors back

You mean the two resistors, right?

Naw, R2 and R3 weren't there

I removed Q2 and Q3 as Graeme showed in his picture so I could solder in the jumper wires

Trey's board has a R/A through board DB15 connector, so it wasn't possible to reposition wires as you suggested

Reposition the wires on the plug, not on the PCB. Undo whatever you have done.

Reverant, there are no wires on the plug. There are pins going through the PCB.

Similar to this: http://www.amphenolcanada.com/Produc...7XXXXAXX0X.pdf

No solder cups. No wires. Pins that are soldered directly to the PCB.