While on a road trip, I noticed that my truck seemed to be exhibiting signs of pre-ignition. It happens when under even a slight load, i.e. going up grades. I remember reading that cam phasers make kind of a pinging noise also, so I'm not sure what I am hearing. I usually put in some Lucas gas additive, but haven't used it for maybe 10k miles or so. I plan to adding some fuel system cleaner to see if that helps. I have 2010, 4.6 with only 62,000 miles. Has anyone else run into this?

 

One of the things conspicuously absent from my owners manual that was well known "in the olden days" was if under heavier-than-normal load, try one grade octane higher. If it goes away it's normal pinging though some maintenance may be desirable. If it doesn't go away dig deeper to find the problem.

There's a lot of variables that have to be asked about: fuel octane used, what % alcohol, how's your maintenance, i.e., spark plug maintenance, when did you last replace the air filter? Darn near anything could cause what you're hearing, time to start eliminating possibilities.

 

It does run good and I am close to **** about my maintenance (as long as I know what needs attention). Air filter was brand new before our trip, but the spark plugs have not been changed yet. I'm not good about using top tier gas though, partially because I don't always know. These are supposed to be good on 87 octane, right? And usually the computer compensates somewhat for poor fuel choices. I live in an area where the ethanol is supposed to be no more than 10%. We'll see what happens after I add some cleaner. I still have 1 final leg of the trip left today, about 150 miles. I should know something by then.