Runs good cold but bad when warm

Asked by Oct 18, 2019 at 06:44 PM about the 1991 Chevrolet C/K 1500 Silverado RWD

Question type: Maintenance & Repair

Truck runs fine with no
thermostat. Put in thermostat and
when temp gets 160 deg. It shifts
into overdrive at 45 mph and
boggs down. Will not down shift
when slowing down or up a steep
grade at low speed. Sounds like
its spark knocking and smokes
out exhaust. Take out thermostat
and runs and shifts fine. Have
recently put in new radiator,
heater core, and transmission
filter. Any ideas would be
appreciated. Thanks

1 Answer


a thermal sensor~ on the intake snorkel~

Your Answer:

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