spec1sef

I have a 1990 Miata Turbo with DIY Megasquirt ECU. I am trying to dial in timing. I checked timing on my car and by aligning the notch on the pulley to match the "l" mark on the timing cover when cylinder one is at TDC. Both cam pulleys match the markings on timing cover back plate as well.

However when I start the car that notch mark retards about 20 degrees or more. So when looking it facing the car that notch is to the right of "l" mark on timing cover. I have the CAS turned all the way up to maximum so I could narrow the gap between the notch on the pulley and the mark on timing cover (bringing the notch toward the left side when facing the engine). I have also tried setting Tunerstudio to fixed timing and used trigger wizard to set timing to "-20" which is the maximum value to try to bring the notch as much close to "l" mark on timing cover but it's still off by 20 degrees or more.

How is this possible? Why isn't my pulley notch matching the timing cover "l" mark even after adjusting CAS and setting trigger wizard to -20. Adding positive values moves the notch to the right (away from the "l" and "10" mark).

I have attached my base tune. I have gotten my car to idle but worried about mismatch timing between TS and actual timing on the car.

Braineack

iTrader: (62)

what in the world are you doing...youre doing it *** backwards.

and it's "T" not "I" for TDC.

put the CAS back to where it was and dont ever touch it again.

set your fixed timing to 10° dont ever touch it again.

adjust the trigger angle between -90 and +180 until you timing reads "10" with a timing light.

go back to timing map.

go back to boosting.

spec1sef

I had to set CAS to that setting to get the car started. It would not even start if it isn't set there. Fixed timing is already at 10.

As far as trigger angle Tunerstudio says pick trigger angle between +/-20. You are referring to -90 and +180. Are you referring to Basic Setup > Tach input/Ignition Settings > Ignition Options > Trigger Angle offset deg (currently set to -20)?

asmasm

iTrader: (1)

If your CAS is rotated all the way to get 10 degrees on a timing gun, you have some combination of horrible TS settings or a failed damper.

Braineack

iTrader: (62)

or you completely botched your TB install.

spec1sef

I have CAS rotated all the way and I am still not even at the "T" mark. I will check the damper tonight.

spec1sef

I checked the timing. The notch on the pulley lines up with the "T" mark on cover and both pulley marks line up as they should while cylinder 1 is at TDC.

I am guessing it's either a TS issue or the pulley is bad. I only remember seeing one notch on the pulley from what I have seen online so far there are two notches. One lines up to "T" and the other one at "10". Is that true for 1992 Miata?

Braineack

iTrader: (62)

you have one notch. it should be at T when you set your timing belt and the pistons should actually be at TDC.

did the car run before the MS install?

asmasm

iTrader: (1)

OP:
Did you do a timing belt job at the same time you installed megasquirt? If not, did the car run normally before installing megasquirt? Did you ever check the timing before installing megasquirt?

spec1sef

Actually I have had this car running on Megasquirt for over 2years now. Since the rod bearing started making noise I decided to rebuild the motor few months ago with stock parts. Put it back together and checked all timing marks at least three times by spinning the motor by hand to make sure everything lines up.

CAS is the only thing I forgot to mark where it was set previously. On top of that two injectors just decided to not work after being stored for few months. So I had to use a new map and different injectors. After hours of tinkering the only way I could get the car running if I set the CAS turned all the way and setting trigger wizard to -20 to bring the notch close to the T mark. Anything else I do it moves the notch away from T mark toward the right.

So as of now it starts and idles fine but my ignition table show 22 degree advance at idle but on the pulley I am still at least 20+ degree to the right of the T mark. If I set the fixed timing to 10 then notch moves even more to the right. Timing mark ends up around 3 O'clock position when facing the engine.

I am guessing I need to set the trigger angle you were referring to? (-90 to +180)?

Is my ignition settings correct?

spec1sef

Ok I checked the timing again last night and it's spot on. The notch on the pulley lines up with T mark on the cover while cylinder 1 is at TDC. When I set the timing in TS to Fixed at 10 degrees I don't see 10 degrees on the pulley with the timing light. It's off like at least 30 degrees retard (toward 2 O'clock position when facing the engine).

How do I get it to line up to 10 degree mark? Otherwise car idles fine but I am afraid when tuning my numbers will be just a guessing game as far as ignition table is concerned.

asmasm

iTrader: (1)

I didn't see anywhere in your posts, did you actually confirm TDC by putting something in the #1 spark plug hole and then turning the engine slowly to find where TDC is? Seems most likely that your damper has rotated on itself. If you don't plan to replace the damper now then find TDC and make a new mark on it. If it is off by a lot the thing is probably way beyond useful and your timing will be all over the place.

Once the damper is sorted out, in tunerstudio, set timing from table to fixed. Then use the trigger wheel wizard to adjust base timing until it is at 10 degrees indicated by your replacement damper or your new mark.

Edit:
I started typing this before your last reply.

You need to re-confirm your timing belt hasn't moved a tooth. Post a picture. Then set the cas back to somewhere reasonable in the middle of the range. Set tunerstudio back to 0 trigger angle offset. Set timing to fixed. Attempt to start the car. Then mess with with the offsett number in the trigger wheel settings until it starts. Fine tune from there.

spec1sef

Sounds good. I will try it this weekend and post back results with pictures.

spec1sef

Ok I am stumped. Checked the pulley and there is no slippage. Timing marks line up fine as they should. You can even see the notch on crank pulley lines up fine when cylinder is at TDC. As soon as I start the car it moves to 2 O'Clock position when checking with timing light.

asmasm

iTrader: (1)

Do you still have -20 in the tunerstudio crank settings and your cas at an extreme angle?

spec1sef

I have CAS set in the middle somewhere. Timing is set to Fixed 10 degrees in TS. Trigger Wizard is set to 0. Can't get it to start. Then I gradually go up to 10 and nothing. So I start backing off until -3 and she backfires. Since I have open down pipe it was loud shotgun sound.

I cannot get light on the timing light. I am getting spark confirmed with spark test light. So now my new puzzle is why the timing light not getting signal?

I tested it on my other car and works fine.

spec1sef

I rechecked timing for the 4th time now just to make sure I didn't miss anything.

So current issue: Can't get light on timing light when hooked up to cylinder 1 spark plug wire. It's an actron inductive timing light.

I can't verify where the timing mark is when cranking. Setting trigger wizard to 10 doesn't do anything. Setting it to -3 back fires pretty bad that I am scared to try again.

Here are timing pictures.

spec1sef

Are my settings correct besides the Trigger Angle offset?

Do I set the "Use Prediction" to "1st Deriv Prediction"? Does it matter?

asmasm

iTrader: (1)

I guess I don't really understand the problem at this point? You verified that the mechanical timing is all in line. Now adjust your tuner studio settings so your base ignition timing is correct as seen with a timing light. If your cas is still off at a wonky angle you will end up needing to put a huge number into your trigger angle offset. That isn't really a problem, it's just weird.

All that is left to do is switch the ignition from table to fixed, and then sit in front of your car with the timing light and adjust the offset angle until it lines up. When your timing marks line up you know you have the base timing set correctly. Switch tuner studio back to table and go back to tuning the car. If you really can't get it to line up with a maximum of 20 degrees in tuner studio you can probably type in a bigger value by editing the msq. I think it is mostly likely you have the CAS at the wrong extreme angle compared to the number you typed in and they are canceling themselves out.

Which spark plug wire are you using for the timing light?

spec1sef

Wire #1. Cylinder closest to the timing belt. I completely understand your direction. After re-doing the timing belt last night I set the CAS to somewhere middle. Set the TS timing to fixed at 10 degrees. Tried to crank the car it tries to start but doesn't start.

Timing light would not even pickup signal when cranking so I have no idea what value to put in the trigger wizard. If I go below zero she bacfires and if I go positive value no start. I verified spark is happening with an inline spark light.

I will try lowering the fuel values, maybe too much fuel causing backfire which is very scary.