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Discussion Starter #1 (Edited)
Hi
Can start of with that the truck had missfires in higer revs before i changed the cylinderhead but anyway now after the head replace i cant get rid of the missfires at idel speed ? I have the tech2 instrument and the missfires has always been most on cyl 2 before and after the head replace and some on cyl 4,5

the things i tested is:
Cleaned throttlebody
Ground and power connections checked
CKP sensor replaced
MAF sensor both replaced and cleaned
MAP sensor replaced
Tank vacum sensor replaced
O2 upstream sensor replaced
No vacum leaks
Switched position of fuel injector 2 and 3
Updated ECU with latest software
Fuel filter replaced
Borrowed ignitioncoils from another truck
Replaced sparkplugs with new original ones
The camshaft actuator seams ok screens are fine
compression test done


Any tips would be appreciated

// Andreas
 

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:welcome2: How many miles on the cats in the exhuaust system? If they are bad your engine will not breathe correctly and give the PO 300 misfire code.
 

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maniac mechanic
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5,779 Posts
leak down test, a bad cylinder can still make compression. You are more interested in it's ability to retain that compression.
 

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Discussion Starter #6 (Edited)
thx for the tips

The truck has 96592mi on it

Timing chains are correct

Done the leakdown test today and it looks like that the cylinder 2 is bad after all so i must remove the cylinderhead again the valves are leaking.

The cylinderhead on my truck is refurbished not replaced as the TSB for p0300 says
Im going to leave the cylinderhead to the company that refurbished it and see what they say about it on thursday


// Andreas
 
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