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Old 11-29-2008, 04:40 PM   #21
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The coils fire a pair of plugs every time they fire. MS reversed them. Typical problem, but easy to fix.

Originally you had, looking a the coil pack, 3&2 on one coil, and 1&4 on the other coil. And it ran fine on stock ECU. You need to move 3&2 wires onto the other coil, and vice versa.
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Old 11-29-2008, 05:20 PM   #22
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Right. Swapping coils is what got it running in the first place. But I can't explain why 3&4 are nice and rusty in color and 1&2 are sooty. It sounds like a V-twin now, which makes a bit of sense as I'm pretty sure it's running on 2 cyl. Could that be a crank angle issue? Sparks are firing close enough on 3&4 to turn the motor over but 1&2 are somehow too far off? I'm grasping, I know.
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Old 11-29-2008, 05:24 PM   #23
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Take a picture of the spark plug wires. I got a feeling they're wrong still. When you say 1&2 are sooty, are you saying cylinders 1&2, IE, the two cylinders closest to the front bumper? Are those two cylinders hooked to different coils?
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Old 11-29-2008, 06:01 PM   #24
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Yes, by 1&2 I mean closest to the front bumper. Also, assuming that coils are paired, 1&2 are going to different coils. 1 is hooked to the far left pack and 2 is far right. Thanks so much for the quick replies!

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Old 11-29-2008, 06:22 PM   #25
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Do you have a timing light? If so, use it to verify which cylinders are getting spark. If you don't have a timing light, you use the "stick a screwdriver in the plug and lay it on the valve cover and see if it sparks" method. Figure out if you are getting spark on all four cylinders. Also make sure both banks of fuel injectors are on, though if one went off, the plugs wouldn't be "wet" with fuel.
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Old 11-29-2008, 07:19 PM   #26
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I do have a timing light. I'll post results tomorrow. Thanks!

[Raining cats and dogs now. Maybe tomorrow]

Last edited by mj71; 11-30-2008 at 12:35 PM.
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Old 12-05-2008, 08:40 PM   #27
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Alright. It's clear now that I'll only have troubleshooting time on the weekend.

I have great news, and a new question. First, I swapped and re-solered the spark pins on the harness I made so I could put the plugs back the correct way. I then warmed-up the car on the stock ECU.

Fired it back-up on the MS and had the same symptoms, but this time I was armed with a timing light. ALL cylinders are getting spark, but timing is WAY off, causing what seemed to be running on two cylinders. My timing marks don't go beyond about +5TDC, but the mark was well beyond that to the positive.

I loosened the CAS and was able to get the car idling MUCH better, almost normal, just lumpy, but the timing was off the chart BTDC by a wide margin. I also had to turn the CAS completely to the left (If standing in front of the car) to achieve this result.

Turning the CAS to the point where it's at about 16BTDC starts the crappy idle again. I can't seem to get anywhere near 10 and have a decent idle. I also tried just about every number from -5 to 90 on the trigger offset. Some numbers had a decent idle, but always with the timing WAY, WAY off the chart in the BTDC direction. Oh, all of this is with the timing locked at 10* in MegaTune.

Am I trying to fix a square hole with a round peg?
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Old 12-05-2008, 09:29 PM   #28
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Pull sparkplug in cylinder 1, drop a long extension down in it so that it rest on the piston. Turn the crankshaft with a socket and watch the extension to get the motor at TDC. When the piston is at it's highest point, see if the mark on the balancer is reading TDC. If it ain't, new balancer time.
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Old 12-06-2008, 02:25 PM   #29
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Fair enough suggestion, but since it's about 20* out right now let me ask this:

Could the harmonic balancer be bad if the car runs like a champ on the stock ECU with timing set by the CAS to an indicated 10BTDC? I marked the CAS before I started playing with it yesterday and put it back afterwards. The car is perfectly happy with this setting and has seen many hours on a race track set that way.

If the answer's yes, I'll try and get the motivation to bundle-up and do the test.

I've also been reading more and more and am wondering if the Trigger Angle setting is essentially similar between MSI and MSII. It seems like it may not be.
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Old 12-06-2008, 02:35 PM   #30
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Well, it could be "bad" as in- part of the rubber has turned loose and it no longer damps harmonics properly, but still reads true relative to TDC. Or, it could be "bad" as in so deteriorated that the rubber has completely turned loose and the balancer has 'slipped' and no longer reads TDC in the correct place. Either one it's not doing it job.

Well, sound like the balancer is right if it works fine on the stock ECU setting it to 10*. But if I were you, I'd still verify it's spot on just to eliminate a possibility, rather than dismiss it as unlikely.

As for trigger angles, I'm not much help as I don't use a CAS. However, I've read people with CAS's run sixty something to seventy something for a trigger angle I believe.
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