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Syncing cams to crank

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Rocketst

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Thread Starter #24
And I've actually ordered a brand new set of plugs and spark plugs. This didn't fix the issue. I noticed an improvement but not a solution.

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MagnetiseST

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#25
Swap the coils from 2 -> 1 and 3 -> 4 see if the misfires follow.

I find it hard to believe that with the cams installed incorrectly or the engine off time that only two cylinders miss. They should all be missing.
 


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Thread Starter #26
Sorry I meant to say coils instead of plugs. I've done this test already but ordered new coils anyways and installed. Like I said problem got better but no solution.

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Thread Starter #27
The next step I did was ordered a brand new fuel rail and new injectors and this also helped but no solution.

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MagnetiseST

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#28
Sorry I meant to say coils instead of plugs. I've done this test already but ordered new coils anyways and installed. Like I said problem got better but no solution.

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If it got better, it would lead me to believe you have an ignition issue. Unfortunately without one of those gigantic scan tools you cant really test it.
 


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Thread Starter #29
Yeah and even when I took it to a local shop to view the car driving in mode 6 the tech who was with me left confused as hell cuz nothing looked out of the norm... Lol he actually told me if I find out the issue to tell him cuz he's never seen anything like this.

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Thread Starter #30
Nothing looked out of the norm except that on cyl 2 and 3 I collectively had 500 misfires in 10 seconds....

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Thread Starter #32
Can I use the accessport to test frp and determine if the lpfp is to blame?

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Thread Starter #33
So one of the things that mechanic did when I took it in to repair the engine was to verify I had a good pcm by unmating the accessport and updating the pcm. So I know I have a good pcm.

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MagnetiseST

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#35
You could do that, but if it were the LPFP all cylinders would misfire. Did you change the HPFP cam bucket when you put this engine in? Did it come with an HPFP? or did you swap yours over?
 


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Thread Starter #36
I swapped my hpfp in but I ordered a brand new cam tappet to go in.

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MagnetiseST

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#37
I'd say thats good. Monitor FRP on the AP and see if its weird. But 500miss in 10 seconds is 50miss per second. If you measure that vs rpm thats a LOT of misfires.

Assuming is a spark miss:

800rpm idle = 800rev/60sec. 1 spark per every 2 complete revolutions, 400spark/60sec. 400/60 = 6.66666, 6.66 spark per second. 10 seconds should be 66.6 spark per cylinder.
 


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Thread Starter #40
I'd say thats good. Monitor FRP on the AP and see if its weird. But 500miss in 10 seconds is 50miss per second. If you measure that vs rpm thats a LOT of misfires.

Assuming is a spark miss:

800rpm idle = 800rev/60sec. 1 spark per every 2 complete revolutions, 400spark/60sec. 400/60 = 6.66666, 6.66 spark per second. 10 seconds should be 66.6 spark per cylinder.
That's under load at a sustained 4k rpm which was and still is a problem area (rpm wise).

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