Re: 1994 Explorer Pinging
> My '94 Explorer pings horribly whenever I put regular octane gas in it.
> The pinging is worst when I accelerate. I've been putting premium gas
> in it and that helps quite a bit, but it still pings whenever I
> accelerate into a stiff wind. I've changed spark plugs, wires, air
> filter and fuel filter. Nothing seems to help. My mechanic says that
> the vehicle doesn't need premium gas, but it sure seems to run a lot
> better on it. Any help or suggestions would be appreciated.
There's the "remove the shorting bar" fix, which retards the spark 3
"The bar was easy to find, it's in the passenger side of the engine
compartment behind the diagnostic connection block. Look for a
wire with a connector on the end taped to the large harnass leading
into the block. The shorting bar is a small grey rectangular cube
that plugs into the connector. I just grasped onto it and pulled."
There is also de-carbonizing. Carbon builds up in the head and on the
intake valves, effectively increasing the compression ratio and making
little glow plugs if the carbon gets red hot. Both of those things can
cause pre-ignition or pinging. I read an old post by guru Jim Warman
about adding a small amount of water to the intake of the engine as it
idles, "steam cleaning" the carbon out. There are also kits of
chemicals that do the same thing.
Search this newsgroup or the web for "pinging" "shorting bar" etc if
you need more detail.