1999 Ranger 2.5 4cyl pings???
I have a 1999 Ford Ranger 2.5 with 55k miles that pings under load. It
started all of the sudden with a new tank of gas about 3 tank fulls
ago. I have always run middle grade (89) with no problems. At first I
thought it was a bad tank of gas, but has persisted with fresh fill
ups. It idles a little rougher when cold and hesitates some but when
warmed up, seems ok. It may seem strange but when I drive to work in
morning, it rarely pings. When I drive home (same route) in the late
afternoon, it pings persistently. Weather related? (Colder air in
morning, warmer in afternoon!) The check engine light has not come
on... If the check engine has NOT come on, does that mean all sensors
are working? I am currently running a can of Berryman B12 with premium
gas as an initial inexpensive try to remedy. Anybody have any ideas?