NA crank trigger wheel sensor on a NB?
 

I am trying to start my car and I have absolutely no spark.

could this be because of the crank sensors on the NA being incompatable with a NB?


I am using the same coils, coil pack, everything, didnt change a thing except the engine block, which is now a NA block.


all help is appreciated.

Details are needed on your engine management system, particularly the input configuration.

If you were previously using the stock NB crank and cam sensors, then it will not run with an NA engine unless you re-configure it to use the NA's CAS pattern or transplant the NB sensors, crankwheel, and intake cam pulley onto the older engine.

If, on the other hand, you had previously installed an NA CAS into your NB head (which I find unlikely, since you have an MS2) then the problem is elsewhere. In that case, we'll be wanting a datalog.

+1

If ALL you changed was the block and retained all the sensors/wheels from previous setup I think your problem is elsewhere

If you're trying to use the OBDII VR crank sensor on your NB ECU, it's not going to fire up. You need to give us more info, though.

The only thing different is the NA crank sensor, NA block and new spark plugs, everything else remains the same.
What is it I need to reconfigure in the MS2?
Appreciate all the help.

I'm confused.

Were you or were you not using an NA-style CAS previously? If not, the what you listed above isn't "the only thing different." You're also missing the cam sensor, which on your NB engine was on the front of the valve cover on the intake side.

The NA (specifically, '95.5-'97) cam sensor is a VR-style as Sav noted, (so you'd need a different decoder circuit to read it), but the biggest problem is that the pattern it outputs isn't compatible with anything.

At this point, you need to re-wire the car as though you were doing it for an NA. That means hooking up to the CAS which is located on the rear of the valve cover on the exhaust side, connecting it to where the crank and cam sensor used to go on the MS, changing the software settings from "99-00 Miata" to "4G63", recalibrating the trigger offset, and hoping you didn't blow up the CPU by connecting a VR sensor (which has a fairly high output voltage) to an input configured for an open-collector sensor.


When you say "NA crank sensor", are you referring to a sensor which is physically down by the front crank pulley, or do you mean the device which is on the back of the exhaust cam? If the latter, how did you splice it into the NB's wiring?

He has a DIYPNP built by Braineack with my expansion board in it, on a 99. My hunch is that he toasted the short block, found one cheap from a 96-97, and put it in there without reusing the stock NB crank sensor.

when i say NA crank sensor, I am referring to the sensor that is by the front of the crank pulley. I AM using the NA crank sensor on my NB setup, I am not sure if they are compatible, which I am trying to figure out. I do NOT have the NA cam angle sensor which is located on the exhaust side of the head. I have the NB one on the front of the intake side.

I had set the car up on MS2 when it was bone stock....it was running fine, and I had it street tuned, now I am putting in my turbo components and this time around I swapped blocks, and also put in everything that goes into a turbo system, I will take pictures of my setup, including pics of the crank trigger sensor (which controls spark correct?).

awww, no body?

Put the NB sensor back in?

trying, this fucker seems be not able to bolt up to the NA block.


am I wrong?

Mounting point is identical.

https://www.miataturbo.net/showpost....&postcount=104 See my picture, nb sensor.. na block.

NB sensor in, have spark, fires but will not start kinda like with the MS2, crank crank crank, throttle wide open then it would start but would sputter if the throttle is depressed when cold. Cold start need to be adjusted, any suggestions?

Seriously?

whoops, miss type.

Did you just install the DW800s?

they went on with the new engine, yes.

So you installed larger injectors (presumably MUCH larger injectors), did not retune the cold start or VE tables in any way, and you're asking us why the car won't start?

hint: that's why the car won't start

I'm sorry I am just really not that familiar with megasquirt and things to do with it.

still trying to learn all this stiff