Tach not working MSPNP GEN1
 

I have a 1990 Miata with a 2004 Mazdaspeed engine running on MSPNP 90-93 Gen 1. I am using the ignition coils from the Mazdaspeed engine instead of the 90 coils and deleted the ignitor. The MS has a tach signal, I can see it on the computer when I have it connected, however the tach on the [car] dashboard doesn't work. Is there something else I need to wire up to get the signal to the stock tach?

Up to year 95.5 the tach in the gauge cluster was controlled by the coils/ignitor. Since you removed your stock igniter you no longer have have anything powering the tach in the cluster. I believe the MSPNP has the tach circuit built and you just have to enable it in the setting, but I am not positive on that.

are they 4 wire coils? if so all you need to do is add a 1K resistor from ig- to b+ in your diagnositics box.

Can I rehash this topic?

I have a 95 with a NB1 engine, but using the NA coil pack unlike above. Same thing as OP, it reads in Tuner Studio with MSPNP Gen1, but no tach read out. I believe they are the 3 wire coils (will double check tmrw). Never bothered me much since I never look at it, but have been doing some rainy day projects.

If you're using the NA coil pack, I'd venture that you need the 1K resistor from ig- to b+ in your diagnositics box, as well.

I know my '94 did... using the same/identical coil pack that you are.

Then again, I only have experience with my own car. Not nearly as much as the other guys here do.

enable tach on your MS.

I stand corrected. I am using the NB coils/no ignitor. Been a while since I looked.

so 1k resistor it is. thanks Brain

you have a 95. enable tach out on your MS.

Just to be clear, If your chassis/engine combo didn't originally need a tach output circuit, which I believe is 95.5-97, your MSPNP1 won't have that feature. So 90-95 MSPNP1s do NOT have a tach output circuit. You can build it yourself on the board if you'd like, or I was going to send it to DIY for a $75+shipping upgrade, before I bought a MSPNP2 for said project.

To clear up, here's which Gen 1 MSPNPs did and did not have a tach output circuit.

1. '90-'93 MSPNP Gen 1s did not have a tach output circuit.
2. '94-'95 MSPNP Gen 1s have a tach output circuit, but the default base map has it turned off as only the '95.5 cars should use it unless you change the coils out.
3. '96-'97 MSPNP Gen 1s have a tach output that is enabled in the default base map.

All MSPNP Gen 2 and MSPNP Pro units have a tach output standard.

To clarify my car is a 95, not a 95.5 with NB coils, and no ignitor. but because I'm running NB coils I can just turn it on in the MS since it's effectively a 95.5?

why dont you try it...

Well I did try it, Tacho Output and tried all of the pin outs and nothing. Am I in the wrong place? I ask because ECU tuning might as well be hieroglyphics to me. Baby'fied things are easier for me :)

You should be able to turn it on; how do you have the tach wired up?

Its a MSPNP in a 95 with 99 engine and coils. Previously it was a 95 engine with the MSPNP so the tach was operating via the 95 coils, so there are no changes to the wiring to the tach from stock. This is a gen1 BTW.

Tach output should be enabled on JS0.

Can you post your MSQ, and let me know what revision code this MSPNP is?

so if i have a 97 mspnp gen1 where do i locate the tach out signal? do i need to do anything with that sigmal prior to hooking it up to the dash tach?
thanks

If it's anything like the MS2's tach, it'll work perfectly fine, you only need to wire it and activate it in TS. For your 97, it should be wired to the same tach pin of your 97's harness. AKA: No wiring required.

For the '96-'97 cars, the default tune file already has the settings to turn the tach output on.

thanks a lot
for some reason i was under the impression that the dash tach runs of the coil signal not the ECU
thanks again