tink tink tink...

immediately after a fuel stop...

I'm going with bad fuel/filter issue causing a weak injector to ping.

do you have new clear lines? any chance there is air in the lines?

put your stethoscope on each injector and see if you can isolate which one... send it to greazzer...

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!