Please help.....I have an 87 pickup with a 22re. While driving the motor constantly loses and gains power. When parked, i try to maintin a constant rpm but again it surges. While experiencing a loss of power it runs really rough and idles a few hundred rpm lower than normal. I have recently replaced the TPS, fuel filter, cap, rotor and spark plugs. When checking the trouble codes it shows everything normal.

 

Does it change at all with the motor hot or cold?

 

No, and it starts fine hot or cold

 

i had almost the same situation and after workin at everything else i found out i had a broken and worn out timing chain slide.installed new timing set and it ran as good as new.