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Discussion Starter #1
I've noticed that I have the slightest miss at idle. I decided to data log and come to find out it's misfiring on one bank (Driver side bank). This almost only happens during idle and sometimes on deceleration and only misfires 1-2 times per cylinder per 5 miles or so. Almost all tune up items are new including injectors.

A while back, I swapped to PI cams/intake and during that time I changed the head gaskets. I'm starting to suspect the timing being off by just a little on that bank despite me triple checking the orientation of all the components. A couple questions come to mind before I decide whether or not to re-time the whole thing or not. First off, is this a timing issue? If so, is it because of me being "off a tooth" or is it a matter of degreeing the cam? I would think that being off a tooth would create a more dramatic misfire effect than 1-2 misfires over a course of 5 miles, or would it?

I really don't want to re-time the whole thing. help a guy logically deduce what's going on. Thanks.
 

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What are the results of a compression test?

Exactly which cylinders are misfiring? Is it equally across 5,6,7,8?

Has the alternator been tested for excessive AC ripple and correct output?
 

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Before I even read the details I said to myself "I bet the cams are degreed wrong" and I SEE you did a cam change:yup: check the fuel trims in the datalogs and see if there's a difference between banks!
 

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Discussion Starter #4
Thanks for the reply guys. I did a compression check about 2 weeks ago and all were around 180 psi (hot test). The alternator is a new Motorcraft brand. The cylinders 5,6,7,8 are all within +/- 1 misfire of each other.(again, it is hardly misfiring but misfiring none the less and no misfire on bank 1) When I put the cams in, no I did no degree the cams. I knew degreeing the cams would be optimal, but I didn't think that it would cause misfires. Is it a degreeing thing or a chain off a tooth thing?
 

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Discussion Starter #5
I just went out and checked the fuel trims. Here are the results:
STFT are about 1.0 on both banks as can be expected
LTFT: 650 rpm (idle) Bank1: 1.047 Bank2: 1.016
1500 rpm Bank1: .996 Bank2: .998
2000 rpm Bank1: 1.008 Bank2: .996
 

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Discussion Starter #6
Alright, I think I might just open up the timing cover and re-time the whole thing just for peace of mind and with the hopes of improving my sub par gas mileage. I know that degreeing the cam will be ideal but what's everyone's opinion on degreeing a stock pi cam in a npi head? Worth the trouble or just line up the timing marks and be done with it? Also, is it necessary to pull the followers out to re-time the cams, or can I just forcefully hold the cam in place while I put the chains on?
 
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