94 Chevy engine thinks its always cold
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94 Chevy engine thinks its always cold
My 1994 chevy 1500 with a 350 tbi runs a rich fuel mix and higher rpms all the time now. when the engine is cold it usually runs at higher rpms until it reaches operating temp and then the rpms drop. but recently the rpms will no longer drop, but my temp gauge still works. i replaced the coolant temp sensor (2 wire) but that did not fix the problem. all fuilds are at the right levels and i disconnected the battery to clear any codes that may have been there ( check engine light was not on). also i lost cruise control at the same time it stopped lowering rpms once warm.
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My 1994 chevy 1500 with a 350 tbi runs a rich fuel mix and higher rpms all the time now. when the engine is cold it usually runs at higher rpms until it reaches operating temp and then the rpms drop. but recently the rpms will no longer drop, but my temp gauge still works. i replaced the coolant temp sensor (2 wire) but that did not fix the problem. all fuilds are at the right levels and i disconnected the battery to clear any codes that may have been there ( check engine light was not on). also i lost cruise control at the same time it stopped lowering rpms once warm.
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if the issue is just a high idle it may not be coolant related. vacuum leak will cause a high idle
did you check the coolant temp reading with a scan tool? the coolant should be between 80-100*C when the engine is warmed up.
did you check the coolant temp reading with a scan tool? the coolant should be between 80-100*C when the engine is warmed up.
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the idle is fine and the coolant temp checks out good. its when i am going down the highway and my rpms are about 300-500 higher than they are supposed to be when the engine warms up.
is there any way something with the cruise control could cause this? the cruise control is not vacuum on this year it is all electronic and i know there is a black box on the fire wall, there is a sensor on the break pedal, and obvious the stick coming off the column to turn it on and off. could any of these going bad cause my truck to think its always cold?
is there any way something with the cruise control could cause this? the cruise control is not vacuum on this year it is all electronic and i know there is a black box on the fire wall, there is a sensor on the break pedal, and obvious the stick coming off the column to turn it on and off. could any of these going bad cause my truck to think its always cold?
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I wouldn't pull the pan at this point...what i am referring to may be normal operation...not locking up till the fluid is at temp.
a bad tcc circuit may set a dtc
get it to temp, at cruising speed; so the tcc is locked....keep you foot of the gas and tap the brake with you other foot...if there is a slight right rise...the tcc disengaged. modern vehicles run the tcc differently but a 94 may still run this way.
a bad tcc circuit may set a dtc
get it to temp, at cruising speed; so the tcc is locked....keep you foot of the gas and tap the brake with you other foot...if there is a slight right rise...the tcc disengaged. modern vehicles run the tcc differently but a 94 may still run this way.