CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

Intermittant hesitation at part throttle -> WOT

Russell

3/4 ton status
GMOTM Winner
Joined
Jun 23, 2000
Posts
8,493
Reaction score
1,935
Location
Rocky View County, AB
Now that I've got my truck on the road, all the little gremlins are popping up. One of which is an intermittant hesistation at part throttle to wide open throttle while accelerating from 0 - 60 mph. The hesitation is noticeable through all 5 gears, and is bad enough that when it hits, the truck will lose 10 mph until it picks power back up and re-accelerates.

When the truck hesitates, the turbo spools down. The hesistation also appears while crusing, but far less frequently.

I never noticed any hesitations on short runs around the block, even at WOT, but I haven't had the engine up to full operating temperature on an appreciably long run due to the truck not having any tags earlier.

I couldn't tell if there was any smoke when it hesitated, as it is dark outside and I didn't have any traffic behind me to light up my exhaust. I have a slight tinge of blue smoke at an idle, which is a new development as well.

Engine is a freshly overhauled 6.2L, so it shouldn't be blow by, valve leaks or whathave you that is causing the smoke. The smoke smells very richly of un-burnt diesel.

Any thoughts about what may be going on?
 
Now that I've got my truck on the road, all the little gremlins are popping up. One of which is an intermittant hesistation at part throttle to wide open throttle while accelerating from 0 - 60 mph. The hesitation is noticeable through all 5 gears, and is bad enough that when it hits, the truck will lose 10 mph until it picks power back up and re-accelerates.

When the truck hesitates, the turbo spools down. The hesistation also appears while crusing, but far less frequently.

I never noticed any hesitations on short runs around the block, even at WOT, but I haven't had the engine up to full operating temperature on an appreciably long run due to the truck not having any tags earlier.

I couldn't tell if there was any smoke when it hesitated, as it is dark outside and I didn't have any traffic behind me to light up my exhaust. I have a slight tinge of blue smoke at an idle, which is a new development as well.

Engine is a freshly overhauled 6.2L, so it shouldn't be blow by, valve leaks or whathave you that is causing the smoke. The smoke smells very richly of un-burnt diesel.

Any thoughts about what may be going on?

IP timing off or too much fuel, My guess is more IP timing
 
Actually wound up being my lift pump. I've got an electric in-tank pump, the sock fell off somehow and the pump started sucking up some crud that was on the bottom of the tank. The pump has a little screen across it as sort of an emergency backup to the sock, and it was nearly plugged right off.

Cleaned the screen, replaced the sock, and voila, runs like a champ again!
 

Latest Posts

Top Bottom