My '82 300 TDT was running great. Set cruise at 82 mph all the way
across Arizona on I-40, 28 mpg.
I'm back home, but now it won't start. This started at the motel in S.
Utah before crossing AZ. It was 45 degrees and took a jump start to
get going. I had filled up with ultra low sulfer diesel the day
before, and that is all we can buy now in CA where I live.
I took out 4 of the glow plugs (hard to get to #1 without removing
injector lines) and they all glow red within a few seconds of being
connected to 12 V via jumper cables. I cleaned up the tips with a file
and a light touch on a grinder.
I thought the battery might not be providing adequate current flow, so
I replaced it with a new DieHard International. Cranks faster, but
still no go as far as firing is concerned.
The fusable link on the glow plug relay box is good. An ammeter shows
current flow at each of the glow plugs when I turn the ingnition to
Compression is not that bad, the motor provides resistance when I crank
it. Starter is good, motor cranks rapidly, but does not fire. Like I
say, it was running great before this started and even after the first
problems appeared at the motel.
I loosened one of the injector lines at cylinder #4 and cranked the
motor and fuel came out in bursts like it should.
Can those relay boxes go bad part way, that is, still provide some
current but not enough to get the plugs hot? I guess my next test is
remove a glow plug, put the wire back on, ground it and then see if it
gets red when I turn the ignition to start.