falcon

iTrader: (13)

So I'm undergoing a bit of a project here. I purchased Levnubbhin's B18 Blox manifold mated to the B6 flange. I'm going to be attempting to run the Honda TPS (it's a 3 wire) and I also want to try to get the IAC valve working as well. The Honda one is also only a two wire just like the B6.

Is there anything I need to be worried about when attaching the two wires from the NA harness to the Honda IAC valve? I've tried finding out some more information about it but I can't find anything.

Worst case scenario, I could install a switch to flip on when I am doing a cold start. Just wire the Honda one to power and switch the ground?

Ideally I want it to be automatic like it is right now (I only use the IAC for warmup, not for idle purposes since I have no AC, PS or a TPS right now).


What do you all think? Or is it not worth the effort and just delete the wires and the IAC.

The main reason I'm asking at this point in time is because I'm doing a minor wire tuck and if it's too much work to get the IAC working right, I'd rather not have to re-route that clip all the way around into the cabin and then back out through another grommet.


Is the Miata IAC a stepper motor or "on/off".... I do know it only has two wires going to it.

falcon

iTrader: (13)

This is a Honda IAC

http://www.autodynamics-honda.com/hop6telidair.html

Joe Perez

iTrader: (8)

I'm fairly certain that modern Honda IAC valves are of the same basic design as that on the Miata; a solenoid valve which is PWM- controlled. So same electronics, different software settings. See if you can find an MSQ for whichever engine the valve came from, and copy those settings.

falcon

iTrader: (13)

what screen in the msq? the one for the IAC? so if I do that it should theoretically work?

falcon

iTrader: (13)

success.

looks like you're correct. they use the same system with the pwm valve.

http://www.diyautotune.com/tech_arti...onda_acura.htm

Will my board need any modification Joe? It's a MS1 V3 board.

falcon

iTrader: (13)

I'm going to assume that since teh Miata has PWM valve that this TIP120 is already part of a standard MS1 build?

falcon

iTrader: (13)

Joe, since having just read a few TPS related threads it seems that you have a pretty good grasp on how it all works. How difficult would it be to also have the 3 wire Honda TPS routed into the MS to work the same way an auto TPS does? IIRC the Auto TPS is 4 wire?

Joe Perez

iTrader: (8)

If that "standard" build was Miata-specific, then yes. The TIP120 is not a part of the basic MS board, but it's a very common mod and is documented in the build manual as an option. If you post a picture of your board, we can say for certain.

Joe Perez

iTrader: (8)

Very easy. In fact, I used a TPS from a B18B on my '92. I don't have the schematics on my phone, but it's very simple. One wire is Vref, one is ground, and one is signal. The fourth wire on a '90-'97 Miata TPS is a switch that does not get used with MS. The '99 and later Miatae have 3 wire TPSs and the Honda unit will wire up identically to these.

falcon

iTrader: (13)

Nice.

The throttle body I have is a B18 as well.

I don't have a pic of my board, but I'll assume that since my OEM IAC valve works right now that I have it. I PM'd wayne curr to ask. He is the one that built my board.

How hard was it to "calibrate" the TPS, or did yours just work right off the bat once you wired it in?

The Honda TPS's have break off bolts as OEM that I had to slot with a dremel to undo which makes me belive they are not designed to be "adjusted" on the throttle body itself?

baron340

iTrader: (5)

Just as a note, be sure to double check your IAC valve. Honda has used a couple different styles of actual valves in the past. Back in my Honda days I retrofitted a manifold from a d16 onto a d17. Both used a 3 wire IAC, but they were different styles of valves and I fried a connection inside an AEM EMS. Not saying it won't work, just be aware of what could happen and check carefully. I hope you get it working and don't have any stray electricity trying to find a way out through your MS.

falcon

iTrader: (13)

Thanks for the heads up.

I'll do some good research before hand. And the OEM Miata one is a 2 wire IAC so I assume only a 2 wire Honda one will work. I don't have one right now, Lev blocked it off and didn't use it. So I have to find one first . Junk yard here I come...

falcon

iTrader: (13)

Another thing... if I was say too lazy to get the whole system to be automated, could an inline switch be run into the cabin to turn the IAC on/off? For warm up purposes?

baron340

iTrader: (5)

I'm gonna say no on the switch. My knowledge may be flawed, but the way I understand it, those valves open and close rather rapidly or the stepper spins at a given speed based on whether the engine is surging, dying, whatever and is adjusted accordingly. I don't think it's just a valve that opens to a certain position and then closes when not needed.

falcon

iTrader: (13)

I would only be using it for warm up purposes. Right now I have my OEM one only set to operate when warming up.

ianferrell

The switch is a bad idea on a PWM idle valve, they're usually max out at 50-75%, which effectively feeds them 6-8 volts at most... throwing straight 12 at them drastically shortens the life.

falcon

iTrader: (13)

What about running a resistor of some sort? Would that solve the problem? Perhaps... run it to 6 volts max. Or I can try out a few different resistors until I get the idle at 2000RPM exactly on a cold start?

ianferrell

You oughta be fine just running from the megasquirt, as long as its a two wire. The polarity shouldn't even matter.

Matt Cramer

I scoped a Honda D16Z6 IAC valve once on the stock ECU and found the stock ECU ran it at 500 Hz, FWIW.

Joe Perez

iTrader: (8)

Sorry for the brevity of my previous replies. I'm finding that while my cool new phone is very handy for the purpose of surfing the web, trying to type long, scholarly responses on that tiny little keyboard is like driving finish nails with a sledge hammer.

Basically, I installed a B18 TPS onto a modified stock 1.6 Miata throttle body. The shaft adapter that I made allowed me to put the pin wherever I wanted it, so I roughed it in that way and then "fine tuned" it simply by rotating the TPS within the limits of the slots for the screws while reading it with a meter. IOW, pretty much the same way you'd do it on a normal, unmodified Honda.

If you meant calibrating the MS, once the TPS is mechanically set up within limits, you just run the MS's TPS CAL routine, follow the instructions on the screen, and it does the work for you.



Que?



As for the IAC valve, I'm not sure why we're talking about switches, resistors, etc. The thing really needs to be PWM-driven, and I can't imagine why you wouldn't just use the MS for this. Apart from needing different parameters for drive frequency and the various DC limits and ballistics, it's exactly the same deal as a Miata IAC valve. +12 goes on one side, the other goes to the MS through the IDL circuit (with the TIP120 in it).