95 Chevy 1500 TBI Idle/misfire

[b_sepp]

Hello, just wondering if anyone can help me out, I have a 95 Chevy 1500 TBI with 113000 miles that has a few problems, one is that it misfires, expecially noticable when idling, the rpms seem to hold steady (just looking at gauge) but the whole truck will shake. and SOMETIMES, the idle will fluctuate about 200 rpms up and down, but only while idling. I have replaced fuel filter, injectors, plugs (ac delco) wires, cap, rotor, throttle body gasket, and knock sensor. Timing seems to be good and stays good (after replacing knock sensor) I don't know if i should move on to replacing some of the other sensors (tps, egr,iac map???) there are no codes on any of them.
I don't know yet which plug is actually misfiring, if anyone has some suggestions on how to test that i'm all ears. If anyone would like some more info, just let me know. also, i don't know if this means anything or not, but it does have a little cold knock, but it had that when it ran good too.
thank you for your time
Byran

[MT-2500]

How are you testing for miss fires?
Have you run a cylinder balace test to see which cylinders are miss firing?
Can you feel engine miss?

[b_sepp]

Hi, how do i run a cylinder balance test? and yes i can feel engine miss
thanks

[MT-2500]

Originally Posted by b_sepp

Hi, how do i run a cylinder balance test? and yes i can feel engine miss
thanks

Watch rpm change while pulling one plug wire at a time.

No rpm change that cylinder is missing.


Also with a miss good time to check compression.