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Old 03-29-2016, 06:57 PM   #6661
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Am I right in assuming its an ignition issue because its a abrupt loss of power. Where if an injector were failing it wouldn't be as abrupt.
No
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Old 03-29-2016, 07:31 PM   #6662
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x2

Go look at the problem I was having with that in my thread. It ended up being a loose ground that intermittently turned the fuel pump off for a split second...
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Old 03-29-2016, 07:32 PM   #6663
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cool thanks.
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Old 03-29-2016, 08:20 PM   #6664
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NA cam sensor. I've been bringing my laptop and composite logging all my driving. Going back and trying to find it has been near impossible though. Even if I mark it in the log. It really doesn't show up as much in the log. No more than a big bump in the road shows up. But i can feel and hear it.
I doubt you'll be able to see it with an NA cam sensor, there aren't enough teeth and there is a lot of error in the signal timing because of the cam belt.

There's probably power to be had by putting a crank angle sensor on there and gaining spark accuracy.

--Ian
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Old 03-29-2016, 08:45 PM   #6665
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I've looked into it. Almost got a spm damper with a 36-2 wheel. But there is also more power to be found by installing one of the VVT motors in my garage.
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Old 03-29-2016, 10:13 PM   #6666
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Finally got a good log. Captured 4 or 5 events. I'll post when I get home. I believe it's dying coils.
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Old 03-29-2016, 10:14 PM   #6667
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I've looked into it. Almost got a spm damper with a 36-2 wheel. But there is also more power to be found by installing one of the VVT motors in my garage.
Indeed.

At least you'll have something to keep you occupied while you're not allowed to drive anywhere!

--Ian
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Old 03-29-2016, 10:21 PM   #6668
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Finally got a good log. Captured 4 or 5 events. I'll post when I get home. I believe it's dying coils.
I change my belief. No idea what it is. Hope its coils. I marked the log right after they happen. About 5 of them

https://drive.google.com/file/d/0B7v...ew?usp=sharing

Whats interesting is the tach drops all the way to zero when they happen. Which leads me to believe its a coil issue.

My tach is driven by my coils.

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Indeed.

At least you'll have something to keep you occupied while you're not allowed to drive anywhere!

--Ian
I wish. They need rebuilds.
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Old 03-29-2016, 10:54 PM   #6669
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Definitely happens more when hot/warm. Got these logs after almost an hour of driving.
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Old 03-29-2016, 11:10 PM   #6670
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Originally Posted by aidandj View Post
I change my belief. No idea what it is. Hope its coils. I marked the log right after they happen. About 5 of them

https://drive.google.com/file/d/0B7v...ew?usp=sharing

Whats interesting is the tach drops all the way to zero when they happen. Which leads me to believe its a coil issue.

My tach is driven by my coils.



I wish. They need rebuilds.
Tach dropping to zero makes me think the coils are loosing power.

Your logs, when I plot fuel pressure, show the fuel pressure fluctuating when the misfire happens. So injectors are changing when this happens, despite ecu not commanding them to.

My conclusion: Something that supplies power to your coils (tach dropping despite MS staying syncd) and fuel injectors not firing (fuel pressure change despite constant PW during misfire). I think you can narrow down what I'm getting at from this.
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Old 03-29-2016, 11:14 PM   #6671
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I don't have a fuel pressure sensor installed yet. Those are bogus values.
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Old 03-30-2016, 12:32 AM   #6672
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coils or cas
or perhaps the ms is resetting
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Old 03-30-2016, 12:34 AM   #6673
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Ms resetting should have been caught by log. CAS should have caused loss of sync right?

I'm banking on coils.

Currently going around and wiggling wires while idling.
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Old 03-30-2016, 03:57 PM   #6674
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Pulled some toe out because of miscommunication last time around.



Got the misfire to happen on decel. Does not show up on the log at all. Tach dropped to zero, but log shows perfect decel.

Replacing all the coils tonight, checking and cleaning all grounds.

If that doesn't fix it i'll be going over all my coil wiring with a fine toothed comb.
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Old 03-30-2016, 05:05 PM   #6675
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Ms resetting should have been caught by log. CAS should have caused loss of sync right?

I'm banking on coils.

Currently going around and wiggling wires while idling.
Yes and Yes.

Does your MS get power from the main relay?
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Old 03-30-2016, 05:17 PM   #6676
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I believe so. If thats what it does stock. I'll grab a spare main relay too.
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Old 03-30-2016, 05:22 PM   #6677
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Here is the log of it happening on decel. Its the deceleration that starts at 1321s. As you can see there is almost no variation in RPM. The whole time the tach was bouncing of 0 and doing crazy things.
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File Type: msl 2016-03-30_11-00-44.msl (683.4 KB, 34 views)
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Old 03-31-2016, 01:18 AM   #6678
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Well the MS gets RPM from the CAS I think, as long as the MS is powered and the engine is spinning, you could have 4 dead coils and it would still ready an RPM. I think. The tach is your issue, cause that's driven off the coil signals. Correct me if I'm wrong, but the coil fires when it's grounded? Or with a 5v signal? I've dealt with too many ground circuits lately. Why is that 5v/ground signal stopping?
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Old 03-31-2016, 02:16 AM   #6679
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The tach is driven by the tach output on the coil. Which is a different signal than the 5v used to fire the coil.

The tach ouput actually monitors the coil and only grounds if firing was successful. There is a 5v pullup connected to the tach output and tach so that the coils generate a 0-5v square wave

https://www.google.com/url?sa=t&sour...1z2nT9KW44-eiQ (4 wire coil)

Last edited by aidandj; 03-31-2016 at 03:09 AM.
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Old 03-31-2016, 05:01 PM   #6680
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So far so good this morning. But I won't know until I do a real drive this afternoon.
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