Another random misfire

[matuva]

ne more. But this one is a 2003 Silverado.



If I'm correct, there's no cap and rotor on this one.

The guy was cruising, and suddenly, the truck started bucking and run rough.

The truck does start almost easely, iddle a bit high but not rough. The scanner shows DTC P300:



Doing cylinder balance, we found that cyl # 2, 6 and 8 don't even react. We disconnected coils 2 6 & 8 one by one, and even though we can have nice spark, it seems nothing happens inside these cylinders.

Any idea? These gasers are a bit odd to me, especially the ignition system :nonod:

 

[THEFERMANATOR]

Intake manifold gaskets are rather troublesome on the LS engines. They crack and allow a large air leak leading to a misfire and many times a high idle. Also the fuel pressure regulators is another problem area. They go out and it allows fuel to be pumped into the intake through the vacuum line that hooks to the regualtor.