pinging sound

[jeep90]

my jeep has been making this pinging sound all of the sudden under acceleration. now it only does this until its warmed up, then the noise is gone. it has had a tune up about a month ago, and i have been running 87 octane. it is a 1995 2.5 with 95000 miles. any thoughts?

 

[88Wrangles]

Does the rate of pinging increase as the RPM's increase. If so, it most likely has something to do with the piston. If it is a constant sound, as far as the rate of it, it's probably just knocking from the octain being too low (which is really no big deal)

 

[jeep90]

yeah it becomes faster as the rpm's increase. it also sounds a little like a exhaust manifold leak.......i will look more tomorrow.

 

[88Wrangles]

yes it could be an exhaust leak, or, if it's in the engine, it could also be the lifters.

 

[Snitty]

try a higher octane gas first... or some octane booster... see if it kills the sound