Eagle7

I had it idling pretty well, was working on warmup settings, and the leading spark for the #1 rotor stopped working. Spark for #2 looks good. Didn't try to check trailing spark. I put a mark on the crank pulley 180* from TDC, and that's the only spark I get. Watching the CAS with the timing light, it fires at two positions 180* from each other.

I tried another igniter and another spark plug. Didn't expect it to help and it didn't. Swapped the #1 and #2 leading spark cables. Still only runs on #2. Can't see how it could be anything but a MS issue.

I've gone through all the settings from the FAQ, and don't have any deviations that I can see. I don't know if it could be related, but it happened about the time I was trying to get the BAC to work during hot idling. I think I've restored those settings to the FAQ state. I restabbed and tried the 1,3,7,9 wheel settings - no change.

I'm stumped. What do I try next?
msq file: http://www.i2k.com/~mdoane/Files/meg...0601211611.msq

Thanks,

custom13B

You can try doing a continuity test on the coil. Since you swapped out the ignitor you mine as well verify the coil itself is ok. Its getting a signal because the other side is firing. So its worth checking,Good luck.

custom13B

Also are you sure the ignitor you swapped was good?

Eagle7

I swapped the whole coil/ignitor assembly. But if I understand it correctly, the problem couldn't be there. I think there's a single signal to the leading coil/ignitor to fire both the #1 and #2 plugs simultaneously - they always fire together. Both are fired when it's time for either rotor to fire. I guess that's what a wasted spark is? I'm getting the spark for the #2 rotor on both plug wires, but the spark for #1 rotor isn't coming out. I even swapped the wires to the plugs, and it didn't change anything. Acts like the 7,9 setting is working but the 1,3 setting is not.

Thanks,

custom13B

Thats weird. Prolly the only megasquirt problem I havnt had. I guess Im lost too on this one.

muythaibxr

I noticed a couple of things about your msq...

1) you have injector 2 pulsing during cranking... this is likely to flood your engine.
2) your fixed-angle is at 0 degrees.... you should set that to -10 to use the spark table.

Anyway, your spark settings there look fine... I guess it's possible that something got corrupted... I'd suggest saving this msq, and reflashing the firmware, then re-upload your settings from the msq you posted.

Also, make absolutely sure that the potentiometers on the msv3 board are all the way counter clockwise (assuming you have a v3 board).

Ken

Rex4Life

Ken,

Probably a dumb question, but , how many turns are these pots? I've been turning the pot CCW and it doesn't seem to stop.

Scott

custom13B

They dont have a stop, I turned mine until you feel a slight click. Is this correct Muy?

Eagle7

I just became aware of that the other day. Thought I had that changed. I'll take care of it.
I just did that when I restabbed and tried the 1,3 setting. Needed to use the timing light.
That's the conclusion I have come to.
Will do tomorrow.
Pretty sure they are but I'll double check.

Thanks,

muythaibxr

You have to turn very gently or you'll miss the stop... it'll click if you turn past it...

If you turn past it I'm not sure what the resistance is, but it won't be the same as its fully counter clockwise value.

The pots on the v3 main board are 18 turns. So If you haven't hit the stopper yet, keep turning.

muythaibxr

OK, Are you on a 12a or 13B? if you're on a 13B, setting it to 0 is going to cause your timing to be off by 5 degrees. You should set it to -5... I believe on a 12a, setting it to 0 is the proper thing to do.

Eagle7

13B, but I've got a RacingBeat crank pulley with different markings, so I've been using the TDC mark. I'll be heading out shortly to check the pots and try the reflash.

Eagle7

OK, pots were already CCW, tried fully CW in case they were in backwards - then it didn't work at all. Reflash didn't change anything. But...

Put the timing light on the other spark plug cable, and started to see both sparks. Back on the #1 cable and just one spark. So...

My theory at this point is a leaking injector. During each compression cycle there's so much fuel on the plug it can't build up the spark voltage. If that's the case, I don't know why it can spark in time with #2 rotor compression cycle.

I'll start tearing it down tomorrow night to get at the primary injectors.

Thanks for your help,

muythaibxr

well it's good to hear that you're getting somewhere... That's one thing about going with a standalone; often the problem will be with the standalone, but just as often, the problem will be with one of the systems on the car.

jayroc

If you're only getting one rotor to spark, there really can be only one of two things wrong as I see it. Spark plug or the wire to it.
Before you tear apart the whole intake manifold, I would at least swap plugs and see if it changes things..
If it is flooding out, it could very well be a leaky injector, but an easier way to test would be to take out the leading plug, put it in flood clear mode and crank it to see if fuel sprays out. That is a bit dangerous, but I've done it a couple times in the past successfully.

Are you checking spark while it's running or during cranking? Some plug wires don't allow a good signal for your timing light, I've noticed. Especially FC plug wires. Something to prevent interference, I think...

Eagle7

I can get a decent signal to the timing light while cranking, but I've also been checking while running. Even in this condition, it starts quite easily, and if I give it some throttle I can keep it running for a while.

I've got a dual EGT gauge, and since this problem started, I only get heat in #2, which helps me to confirm that #1 isn't firing.

Since both sparks are put on both wires, you can hook either wire to either plug and it should run the same. I've replaced the plug, swapped the plug wires just at the plug end, and swapped them entirely. Nothing will light up #1. Checked compression just to be sure and it looks good.

I'll try your flood clear test, and also try the stock ECU, just it case.

Thanks,

muythaibxr

this shouldn't be the megasquirt causing the problem... If it's firing one of the plugs every 180 degrees of engine rotation, then it's working the way it should. It sounds to me like the coil itself might be bad... just the tower that isn't working of course... have you tried a different ignitor/coil assembly that is known working.

N1XRR

Okay, how about this:

Disable your injectors (flood clear mode)

Remove your primary spark plugs and place them on a metal (grounded) surface somewhere on the engine and turn the car over. Do you see a spark on both plugs? From what I've read, it seems like all of this testing has been done with the plugs still in the engine.

I agree with Muythaibxr, its not the Megasquirt. If one is firing then its getting the proper signal.

Now, have you checked your grounds? Just curious.

jayroc

If it starts and runs, what is the problem exactly?
Does it not run proper? Lots of vibration? Or are you just not seeing rotor 1 spark?
If you have leading spark problems, they can be heard very easily by the tone of the engine. Usually, it sounds louder with a more notable pause in between fires and a notable loss of power.

Intermittent spark is a fouled plug normally. Did you swap it out with a new plug, or replacement?

Eagle7

It starts, but it's hard to keep running - have to keep working the throttle - even so it usually dies. It's only running on the rear rotor.

I agree it's very likely not the MS, and doesn't look like its a spark problem.

I removed both leading plugs, pulled the fuse for the ECU, turned on the fuel pump and cranked it. Heavy fuel cloud from #1 plug hole, nearly nothing from #2. Confirms part of my suspicion. Hehe, the area around the EGT probe in the #1 header runner is even wet.

So I pulled the off the intake and both fuel rails. The runner under #1 primary injector was pretty wet (more confirmation). I now have both fuel rails with injectors tie-wrapped on connected to the fuel lines and sitting in a drain pan. Turned on the fuel pump - no leak (darn). I plugged in the primary injector connectors, fired up the MS, and saw a single priming squirt from each primary injector - then no leak (darn).

I guess the next step is to get a couple small containers and measure the flow rate of each injector. Might be a "slow to close" problem though. Maybe I need to learn morse code .

I do have a nagging thought that this is just a flooded/fouled chamber/plug and if I had worked harder at clearing it out that it might be fine. I did put a good dry plug in, but at that point I guess the chamber was pretty wet. I guess I assumed that if it was running on one rotor that eventually the other would clear itself. Maybe not.

custom13B

Eagle7,
I chased my tail for a week or so to find I had fouled plugs,they were fairly new and looked good. I baught some cheap autolite 2626 plugs just for tuning. If it were me I would get a fresh set of plugs and go from there. I even did a ohm test on my spark plug wires. And a continuity test on the coil winding itself. It aslo helps to remove those trailing plugs to clear the fuel vapor cloud of death. When deflooding mine I removed all plugs and cranked for a good 30 seconds straight with flood clear engaged. Then I threw in a set of 2626 plugs and it fired immediately. Maybe I helped..maybe not but I wish ya luck,Shawn

Eagle7

I'm back in business.

Tested the comparitive steady state flow rate of the primary injectors - no difference. Tried some morse code actuating them - no difference. But I was quite surprised at how much fuel those things put out. 460 cc/min fills up a small container pretty fast.

Put it back together and cranked it without plugs to blow all the excess fuel out - got a lot from #1. Put two fresh plugs in and fired it up. Both rotors worked fine.

I'm pretty well convinced it was just a fouled plug that wouldn't allow the timing light to trigger. Lesson learned.

My saga continues in the "Noisy CAS Signals" thread.

Thanks,

custom13B

Im glad you got that sorted. I had many issues with fouled plugs. Basicaly from what I can tell if the plug is fouled it wont spark at all. I did but a spark plug cleaner and use it for the autolite2626 plugs....I do not use it for the NGK's. The NGK ceramic insulator is too deep and the sand/abrasive gets jammed up inside there. With this cleaner I can sand blasy fouled plugs and they work again quite nicely. This is one oh those harbor freight air powered mini sand blast type cleaners designed for plugs. Since I have a small box of fouled plugs with no actual mileage I baught the cleaner,Im sure someone wont like it..but it works great for me,Shawn

N1XRR

You could have an injector possibly that is flowing more than the other...just keep an eye out for this happening again.