Hello,
Jay Griggs wrote:
> Is my ping problem different from
> everyone else's because my truck pings even when it is cold?
Nope. Mine pings cold, and some else emailed me saying theirs did too. My
experiments/observations continue, here are some recent thoughts:
I have two distinct ping sounds, a loud one and a quiet one. I used to
think I was crazy, but am more and more convinced this is the case. (the 2
pings, not crazy(well...seperate topic)) I'll describe them seperately.
QUIET PING:
This is the cold ping, and almost nothing affects it. I think it's
quiet because only one or two cylinders are detonating. I'm sure Jay's
cold plugs did not help this. I've seen it go away under 3 situations: 10
degree farenheit air temp, quick increase in elevation, and after the
truck is hot and running 91 octane it sometimes goes away. Current
theories are a lean condition caused by low fuel pressure, low pressure in
one injector at the end of the rail, a bad injector or two, bad injector
wiring. It also may be arcing in the plug wires, however rerouting hasn't
fixed mine. It could be I screwed up the reroute, or the factory wires are
so crappy they need replacement. It's likely that a less aggressive fuel
curve will fix this (per Bernd) by giving our somewhat poorly tuned
situation more leeway. However I also think it can be solved by tuning
everything just right, but this is to be proven. It seems so impervious to
various contitions that I thought for a while it was some un-pinglike
noise like an exhaust leak. I no longer think this.
LOUD PING:
This only happens when the truck is hot, and is much louder than the other
ping. I think it's louder because all 8 cylinders ping. Deposits
excacerbate this, so running high octane in the city makes it worse. I'll
bet your cold plugs helped this condition, as would a 180 thermostat. All
I have to do is go on a long trip to burn the deposits, and this goes
away. Even on 85 octane it isn't too bad once the deposits are burned off.
I've taken to running 85 in the city, and I only get this now at very low
rpms and very occasionally.
More to come I'm sure...
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:48:50 EDT