Schematically, it's identical. Less convenient to install, but also less likely to fall out.

I'm still struggling to understand why the engine is running with the AFM removed if, in fact, the transistor is fried.

I couldn't tell ya. I just know that I have the AFM removed with IAT sensor installed to slots 1 and 6 on the connector. Last night, I hadthe fuse pulled out and it idled for at least a minute. I would post a data log but I didn't record one. I can post my tune, though.

Maybe the transistor isn't fried.. But it should be... So I don't know.

FWIW, my miata can and will siphon fuel from the tank, that was with RX8 yellow injectors.

I had the fuel pump relay removed, and it still turned over and would idle but nothing else. I was purposely trying to run the lines dead, twice, two separate times, and it did it both times. I've pulled my charcoal can and honestly have no idea what I've done with it there, it's possible I had pressure in the tank helping feed the fuel down the lines.

My transistor was certainly fried too, like a giant chunk of it missing. I replaced it and pulled the fuse and all is well in the world.

I will take off my sequential module when I get off work and check out the transistor. I will probably just jump the FP to Ground in the diagnostics box (with care so it won't come undone) and call it a day.

Until I get bored enough to buy a new transistor and install it on the board.

I believe it's underneath the sequential board, like all the way underneath on the other side of the DIYPNP.

I don't know how you can't find it, it should be obvious. TIP 125 - high side driver, it's fricken' labeled for you on both sides even.

https://www.miataturbo.net/attachmen...ine=1434487883

yes, cause the MS controls the fuel pump in that config--its how i wire all my 90-93 DIYPNP units

FP jumped in the box means it's always running with key on.

Just to recap, I have a '90 with a DIYPNP and started it with the 10A ST SIG fuse in place- oops. I just jumped F/P to GND in the diagnostics box for now so the fuel pump will come on (and stay on) whenever the key is in the on position.

I am using the attached base tune and it will startup and idle pretty well. I even drove it up and down the street once. I noticed that the car won't produce boost at all. My boost gauge shows me vacuum pressure and the vacuum pressure going to 0 when I give it gas but it will not ever rise above 0.

P.S. I don't know how to post my tune and/or datalog of it idling...

I guess this means that I have a boost leak somewhere... Would having 3mm ID silicone boost/vac lines cause a boost leak? Or is it most likely just tightening down everything again?

you has boost leak.

That would have to be a large boost leak.

Much larger than a 3mm hose.


This may seem like a silly question, but we've been giving very little in the way of hard data and nothing in the way of pictures: Are you sure that the turbine wheel inside the turbo is spinning freely?

Yes, the turbine wheel spins freely. I can either spin it by hand or watch it while I give it gas from the engine bay. It appears to be moving very freely and everything.

I don't have hose clamps or zip ties around any of my boost/vac line connections, though, either. I have them going from MBC to turbo and wastegate, intake mani to BOV, and intake mani to boost gauge. Should I zip tie or clamp those connections? They seemed really tight with the 3mm hose so I didn't bother with it.

P.S. I tried just turbo to wastegate as well. It's a Hallman Pro MBC if that would mean anything to anyone.

its not the vacuum lines. you have a blown coupler or something.

I bought every single one of my couplers new like 2 weeks ago. I guess I could just Tighten all down more?

One of your couplers is off or not tightened enough. I would go and check every single one of them very carefully.

Okay! I'll do that when I get home from work and post an update. Thanks for the help!

I also installed an aftermarket waste gate actuator.. Is it possible that my waste gate flapper door is opening early?

Okay guys, I double checked all of my clamps, couplers, and lines. They all seem very tight. I am still not going over 0 PSI according to my boost gauge when I drive it.

Where should I look to now? I took videos of the turbine, gauges at idle, and gauges under load. Will be on Youtube shortly

Here is the video:

http://www.youtube.com/watch?v=zqt_7...ature=youtu.be

I took everything off and put it all back on today. Boosts safely up to 8 psi now!! THANK YOU ALL SO MUCH FOR ALL THE HELP.

I truly appreciate it.

your car sounded like it was running on 2 cylinders in the video.



you need to l2t.

I can assure you it was/is running on all four. The issue was an exhaust leak where the exhaust housing mates to the manifold. That's why it sounded like a lawnmower and also explains the obnoxious back firing up in the engine bay. I bought locking nuts and those seemed to work.

What does l2t mean?