megator

Hi everyone I have been lurking for a while but have finally come out.

I have installed a MS1 on my mk1 and it wont start!

Some details i have a 95 mk1 1.8 from japan, with ex, filter and a different chip in the stock ECU. The car also has the wiring like a 1.6 94-95

Ive built a MS1 as a piggyback with the inverted spark mod and all the miata mods following braineaks install guide.

All of my sensors read fine, I get spark (when I installed the MS just after driving with the stock ECU the engine will cough just the once), and I get fuel as I can smell it in the exhaust (not much i have to stick my nose to the tail pipe).

I have tried using the Map braniac recomends, plus the ms pnp ones and i dont even get a hicup out of the engine. It is very cold round here lately, 34 farenheit this morning and my battery is not the best (about 30sec of cranking and she is dead) voltages from 11.5-12.5 I cant seem to get the car started, i havent had a play with pulse widths yet but it seems odd that I cant even get a cough out of the car.

I am now at a loss as to what to check next so any help is appreciated.

What do the stock injectors look like? (maybe i have 1600cc ones and need a much greater pw than the base maps provide)

Could my timing be so out that it wont start?

Also for some reason the rad fan comes on some times and in megatune the box fan output 4 lights up. I cant think if why as i have not installed the fan circuit. Which makes me think something must be shorting?

Cheers

jhad

if you have fuel and spark but no fire you should verify your timing marks are correctly aligned or try loosening your CAS and try repositioning it and crank it

Joe Perez

iTrader: (8)

One of the more common mistakes on a first-time build is to reverse the two spark trigger wires. On the stock harness, these are the brown and brown/yellow wires. If they're swapped, the engine will cough every now and then, but won't actually start. Try swapping 'em and see if that does anything.

As for injectors, the size difference between the stock 1.6 and 1.8 injectors is small enough that your cranking PW table should work either way.

Braineack

iTrader: (62)

if he followed my diagrams this shouldn't be an issue.

megator

I havent had a play with the cas sensor, but is it not possible to achieve the same result with the ms if i change trigger angles? Im hopeing to get a timing light on the weekend to check and set timing

I have checked my harness and it is just as braineaks guide says it should be pin 31 goes towards the ribbed side of the conector 2 spaces to the left of the 4 .70 contacts on the smaller plug and 36 is just underneath it.

I have stuck the stock ECU on reconected the MAS and removed my vacume line. However now the car runs very badly. It idles and picks up okay, but there is literally a cloud of fuel coming from the exhaust. Also the injectors tick a lot louder than before.

Any ideas as to what that might be?

I refited the ms after the stock ecu and for a second it seemed like it was going to burst into life.


For some reason I feel like maybe there is not enough fuel in the car from the MS alone. Is there any reason why the signal from the MS to the injectors would diminish? I guess im trying to say is if the MS is sending a signal for the right amount of fuel and this isnt getting to the injectors then it wont work but why wouldnt that signal get there?

Would it help if i get the voltages at my injector plugs while I crank?

Braineack

iTrader: (62)

did you flash the unit while on the car without unplugging ignitors?

megator

I DPed by accident!

megator

I think i did but isnt thats what the spark invert mod is for so that i dont fry my coils?

Also is flashing the same as loading or tweaking a map? or is flashing reserved for code changes and easytherm? if so I have never flashed the ecu on the car only using the STIM

I drove the car for a while on the stock ECU and it seems the car is fine now. Still smells rich but only if i get right up to the tail pipe. It drove like normal so im guessing there was fuel in the ex or the ecu just needed to recalibrate. I know my old car used to run like a pig for 500mi after disconecting the battery and before it adjusted itself.

My plan now is to pull each plug and check for spark and fuel individually. How much fuel should I be getting? ie should i see a plume of it come out of each cylinder?

EDIT: I just thought, all my grounds from the MS do not go to the same place but are all hooked up. I split them to different pins, all of which ground. Is that a problem?

megator

Okay had a play today and it turns out that I get no spark on 2 and 3. But I found the issue already it was incorrect wirring of the ignition mods. One wire went to igbput not ign.

Everytime the car is run on the stock ecu and then i swap over to the megasquirt it does cough just doesnt quite start. This makes me think it must be timing. I know my loom is okay and I havent flipped any wires round. Could i have changed the spark by that much just with the MS settings?

Joe Perez

iTrader: (8)

Disconnect the fuel injectors' electrical connection. Apply some white paint to the face of the crank pulley around the area of the timing notch, so that it is easily seen. Connect a timing light to the #1 plug wire, powered from a source other than the vehicle's battery. Have an assistant crank the engine over on the starter while you observe the pulley with the timing light. Is the timing mark anywhere near the reference mark? If it's 180° out, you have swapped the two ignition trigger wires. If it's just very far away from the mark, but within the correct half of the range, adjust in software.

megator

Is it possible to switch the wires for the CAS so that it reads 180 degrees out?

Joe Perez

iTrader: (8)

Switching the wires of the CAS would result in an unresolvable signal. The patterns on the CKP and CMP lines are very different, and it's doubtful that the ECU would even recognize them and generate an RPM reading, much less fire the plugs.

jhad

there are two places to put the CAS bolt you can actually rotate the CAS 180 degrees. there is one down inbetween the coils and the CAS (CAS plug faces down), and the other is on the passenger side of the CAS.(CAS plug faces up). I noticed this when i put mine together bc i had my CAS plug facing down and when i looked at the pic in the ms manuals it showed the cas plug up on their car. tried it and it worked for me.

megator

DOH! well okay thanks for all the help.

I hope I can make some free time tomorrow to try that out. Also could I not just switch the ignition signals? This should give me a 180 rotation in spark.

Ill post a vid when it works!

Joe Perez

iTrader: (8)

Yes, reversing the positions of the brown and brown/yellow ignition trigger wires is the second easiest way to accomplish a 180° reversal of the spark. The easiest way is just to swap the plug wires from one coil to the other.

Reversing the two wires from the CAS will simply make the engine not run at all.

megator

Haha there are many roads that lead to rome.

Well id rather do the MS wires, so i keep the plugs in oem order ( I can be ---- like that), I dont want to touch the CAS as I changed the seal last year after it caused my heater hose to burst. So in between twisting an oring or resoldering a wire its an easy conclusion. If i just swap the wires from the spark out inverted mod, that should work?

I cant wait to get it started! I got a knocklink yesterday and im just waiting for a wb

Joe Perez

iTrader: (8)

Danger, Will Robinson!

The SparkOutInv setting which is referenced in the "improved spark output circuit" changes the on/off polarity of the outputs, it does not in any way affect the relative position of the outputs. IOW, it does not make the #1/4 output and the #2/3 outputs change positions.

megator

Yeah I get that, I did the mod u stickied. Very intresting BTW im an engineering student and i quite enjoyed it.

What i was refering to maybe too vaguely is if i switch the wire from R24 from IGN to IAC2B and that from R28 to IGN instead of IAC2B, I should get the same result as switching coil plugs.