Q: My truck makes a fluttering or ticking-rattling noise when I accelerate. It only seems to happen at higher speeds (50 mph and up).
Friend said it was too low octane fuel but higher octane did not help. Truck does have aprox. 70k.
It also stalls when I start it in the morning. Just the first time, when I restart it it runs fine.
The sound it makes though is hard to describe. Not a heavy rattle but a sort of light flickering sound. But it is getting noticably louder as time goes by.
A: Could be carbon build-up on the pistons, causing erratic flame travel in the combustion chamber... 'pinging'......
Decarbon the engine and use a high grade fuel for a few tanks.... also an octane booster can help..... Ed