93-p-pumper

Hey guys so my truck has been running fine lately except I went to visit my parents 4 hours away last week n climbing a pass my truck started to run like it had air in the lines, ran rough, wanted to die if I let off the pedal if I thevered it I could make it wanna pick up RPM's again then some times RPM's would hang. It with it till I got lower down like below 5k feet. Coming home it did the exact same thing on that pass. I wanna go back in a few weeks but I don't want this problem again. I can't find any fuel leaks. So I can't see it being air getting in but that's all I can think of. Anyone got an idea?

infidel

I live at almost 5k and haven't noticed a problem but my understanding is timing higher tham 16° can cause problems at high elevation.

93-p-pumper

My timing is stock as far as I know.

HOHN

Timing was my first thought, too.

It's worth confirming.

Higher altitude benefits from higher compression and less timing.

JH

whiskers

Check your air filter. if it's marginal it will cause problems at altitude, thinner air.

joem

the 6bt should be able to create the same required boost PSI well above 15k feet as it does at sea level- they use PSD and cummins on MT loa in Hawaii at 16,000 feet and during my tour I still saw 20psi when the guy was at 1/4 throttle, maybe something that is more effected by thin air like fuel cap, cracked lines?

93-p-pumper

Air filter is new, I wanna get a timing gauge, I tightened my gov springs about a month ago that shouldn't do it though. I have no fuel leaks either.