Quote:
Originally Posted by iqraceworks
Well, I finally got around to doing some more troubleshooting on my rough idle issue that popped up a while back. Did a compression test...all are 160-165psi.....except #4. It's only 55psi 😕 what's the best way to figure out if it's a ring/piston issue...or possibly a valve/spring issue? The plug for #4 looks pretty dark and sooty.
I guess that either way, the head needs to come off first. Right?
|
That’s bad news. My symptoms are identical to yours where there is a very slight stumble not visible on rpm and one plug is dark and sooty. I’d have thought that much compression loss would’ve been more than just a slight stumble at idle. WOT would feel like there’s no power or mpg would suffer.
Do you have to hold the throttle body open when doing a compression test on N54? If so how?