Bad idle

engines
pickup
#1

i have a 1987 chevy pickup that as a tbi 350 in it. it startes great and idle ok then cold but it has a lope. when it warms up it tends to lope more and die. it was about 111,000 miles on it.

#2

Off hand, I’m going to guess it’s the temperature sensor for the ECM. This will tell the computer when the engine is ready to go in to “closed loop” mode (where it starts taking readings from all sensors and using them to calculate the proper fuel mixture and timing), and if the computer always thinks that the engine is freezing cold, it will cause it to run extra rich. This is the same kind of effect you get if the choke is stuck closed on a carbureted vehicle.

Does the check engine light ever come on?

#3

no it dose not

#4

could it be the idle air contorl valve

#5

What is a “lope?”