The above mentioned truck has a unique problem,the check engine light is on,so I take it to Auto Zone , they check it and say "ACT indicated
-40 degree circuit open " well they sold me a sensor that screws into the intake manifold "ACT sensor",I disconnected the battery while installing as instructed,the light does not come on at first,but after about 45 to 60 seconds the light pops back on,so I go ask a friend who is a supervisor at the city maintaince garage,he tests it and says it's the MAP sensor that's the problem,replaced that sensor,no luck,the truck is using excessive amounts of fuel, around 10 mpg and I would like to correct this problem asap. Thanks for your help, Frank Smith Greenwood,Ms.