Could the tune be causing misfires after cam install on my 4.8
Have a odd issue and im trying to just cover all the bases before i take this motor apart.
Have a 03 4.8 that i installed a vinci 045 cam 278/286 585.585 115+5
motor has long tubes and a exhaust
Since installing the cam its had random misfires in the same cylinders.i have turned off the p0300 code moved the coils and injectors replaced the coils,replaced the wires ,moved the wires,installed new plugs,moved the plugs,rechecked the cam to see if it was off a tooth,checked the pushrods and rockers and all check out so far
issue is the missfire isnt present at idle but under throttle under 3k it misses and the ses light blinks ,Under full throttle it has plenty of power and does not miss.when cruising at 65-75 mph on cruise control has a miss and occasional stutter and the Ses light Blinks .has a slight pop in the exhaust at times but its very occasional
Attached is the current tune . will get a log fine later today to post but the o2s are switching properly and maf seems to be inline but will re check that as well.The truck idles fine and if you floor it will rip up to redline .Bottom end feels a little sluggish but above 3k it seems to gain steam and run.
kinda at a loss here and want to make sure its not a mechanical issue that i need to dig for .Engine ran perfectly fine pre cam.
any help would be apreciated have tuned a few cams before but this one has me for a loop
Do you understand that misfire detection is looking for smooth crank sensor rotation like a stock cam provides. A cam that has any lope will upset what stock misfire detection tables are set for. You either need to put bigger numbers in the misfire tables to desensitize the misfire detection or max them out out and eliminate misfire detection all together.
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