MS3 no-spark (REV built)
 

The car in question is a 94R, factory wiring, with a VVT swap done as detailed in the "Ultimate VVT swap" sticky.


Got the motor, in, MS3 plugged in, MAP sensor line, TPS calibrated, and I believe the wideband is calibrated (not sure as the car won't run).


I sent the head to the machine shop, re-timed the motor and replaced the timing belt. Timing marks line up, and Cam shaft lobe position verified. Crank sensor plate was installed with the center bowl depression facing inward at the crank, not the balancer. I also reversed the plate as a test, still no spark. I did verify the sensor having the correct gap to the trigger wheel.


I'm using 01+ coils, but the factory coil connector blue wire (94 chassis factory 12Volts), shows no power. I plugged in the stock 94 computer hoping the get power, no dice.

Then I find the 80amp main fuse is blown (no idea how, it was fine last week when I pulled the engine), so I replace it. Still no spark, still no power.




I'm using TunerStudio, Fuel injector Load is reading 100% (because the circuit is closed I assume?), but RPM reads "Not synced".

The program also shows "not-ready" in the corner.




Anything obvious I seem to be missing? I thought I'd check the forum while I waited for the sun to rise in Greece.




EDIT: MAP is reading 100kpa (I'd guess this is about right, as 1ato is 100kpa, that puts the shop at just under sea-level).

The drivers side ground is connected at the dip-stick mounting bolt (as the car was originally). The intake side only has 1 ground, which I have on the intake manifold.

Are you getting RPM in TunerStudio while cranking? Log?

No rpm signal via gauge. I'm about to pull off my plug and play harness and do a continuity test to confirm everything is going to the right input/output.



Log (hopefully) below.

Plug and play harness for CAS - converted to 01+ Cam/crank sensors checks out for continuity, and location of wires.

Would the Crank-sensor be the RPM pickup on the new-setup?

Also Pulled up the "test mode" feature. Output test mode inj/spark.


I plugged in the #1 plug wire (run by #4 coil pack in wasted spark), grounded the plug to the header. No spark, when set at coil A,B,C,D.

If you don't have 12V at the coils (blue wire), they won't work, so find that first.

With no RPM signal, the ECU will obviously not send fuel/spark, so you need to see why you don't have RPM, use composite logger for that (post the log here if you need help with that).

Now have 12V at coils.

Here's a log of cranking, one RPM gauge reads 0 constantly, the other is stuck at 99.Xrpm.


Bad crank sensor? The OE Tach input for the 94 coil pack isn't connected, but there's nothing to connect it to. How does the OEM VVT engine derive rpm? Cam or crank sensor?

Cam sensor is brand new.



This log includes 2 cranks, ambient temp about 60, jump pack booster hooked up because the battery is getting weak.



Map is now all weird too.

From my understanding the factory 94 tach/wiring works as such.

5 wires total (6 plug connector, 1 not used). Blue power, black ground, brown and brn/yel are the signal wires to the ECU. The 5th wire is black/white, and this is the output to both the factory tach, and the ECU itself.


So, with my current wiring, I do not have said tach output wire tied into anything, it's just heat-shrinked shut. CMP/CKP each get power and ground, and their respective signal output to the ECU. My understanding is that the MS3 would derive its' own tach signal from other (non-specified) sensors.




So, that would mean that the factory tach output wire which went to the factory coil packs is now irrelevant, correct? If so, how is MS3 intending to pick up the required RPM signal? Does it run directly off the crank sensor?

Okay, 1 issue fixed.

Cam/Crank signal wires to the ECU were reversed. 100% my fault, had my connector upside down when I pinned it.



Tuner studio now reads "ready", in green, in the left hand corner during cranking.


However, I still am not getting a tach signal, rpm readout just says "100", and the factory tach in the gauge cluster is not moving.


Cam sensor is brand new, I'm about to swap out the crank sensor for a new one for the hell of it.


Does this shed light on what may be the problem? I also attempted to start the car with the ignition set to "CAS 4-1". The engine is using NB sensors, but they're wired into the factory CAS wires, which feed the MS3. Should I leave my igntion set at the original "Miata 99-05" setting, or due to my wiring, is "CAS 4-1" the correct setting?



EDIT: I also quadruple checked the mechanical timing, it is still correct, no movement of the marks.

Leave it at Miata 99-05, grab a composite log.

I selected sensor 1 and sensor 2, which I believe are the cam/crank signals.


EDIT: Let me know if you need other signals graphed, the car is at work with me.

Did you say you are using sensor 1 and sensor 2 for cam and crank input?

Post MSQ before doing anything else.

The megasquirt uses cam and crank to figure out the RPM, similar to how every other ECU does. The coil tach output is JUST for driving the tach. Which you will now do using the megasquirt.

How did you wire the cam and crank sensors in?

Ah, gotcha about the tach. Ignition stuff is wired with jumpers for basic testing only. My new connectors will be here friday.


I used the base inputs from Rev. The waveforms appear to be the cam/crank signals.




Wiring:

I clipped off the factory 94 CAS connector, and spliced in GM weatherpack connectors.

One is black, this feeds power and ground to both sensors. There's a splice after the pigtail, so they share power/ground like the 94 CAS. Both are getting power/ground in the correct locations.

The other is white, this is my signal connector. I originally pinned it backwards (upside-down, whatever), so my cam/crank signals were reversed to the ECU. This has since been remedied.




Below is the .msq - Let me know if it's not attached right.


I find it VERY unlikely that the PNP unit Rev built/base-mapped is the source of the problem. My sucking, is likely the source. :facepalm:

The log you posted is a normal log, it's not a composite log (in the "Diagnostics & high-speed loggers" tab).

New, actually composite log, below. I was running a standard log while I had the comp. log screen up.


TPS is moving with little blips of the throttle.

There are 3 cranking attempts.

I repinned my coil connector after one got loose. New pigtails should be here today to eliminate that issue 100%.

EDIT: Coil connectors fixed, power at the top-most pin, signal in the center, ground at the base.

FWIW: I'm using a battery charger to maintain the battery, and while cranking I have it set to 12v Start.

I doubt this would effect the MS3 in anyway, but I thought I'd mention it.

Just a dumb thought.


My coil wires are run through the OE 6 plug connector. The OE 94 coil pack uses 2, 4 plug connectors. In the factory coil setup, two 6 plug connectors are looped to each other, which feed the two 4 plug connectors into the coil.

Is my system of tapping into the factory 6 plug connector okay? I have power/ground at both COP plugs, and all of the wires match the color chart.

No cam signal detected. Check your wiring for the cam sensor.

I reversed the power and ground (I think AllData has messed up diagrams). Colors all agree, but some plugs seem pinned backwards.


I can see what I think is the cam signal (red) in the log.

The center wire in the plug for the cam sensor, has continuity between itself and blue/yellow, cam input for the 94 harness.

EDIT: Also checked all fuses for continuity in the engine-bay fuse block, and the footwell fuse block.