MIKEMOKAS

hey guys! last couple of months my truck has been doing this idle surging thing on and off, but it just recently started doing it all the time after warmed up now.

ill be doing like 65 down the highway for like 5 miles to get into town and ill go to push in the clutch and it will idle at like 550- 600ish rpms for a couple secs and then it will start surging. but it i hold it at like 800-1000ish rpms the motor sounds fine...

i guess im going to start out at the fuel filter, i just bought on at the auto parts store for like 15 bucks.. so ill hold out on installing it for a little while to see what you guys have to say...?

for what its worth, my tps is unplugged, seafoamed a while back...

i could also adjust the idle, but then again i kinda dont wanna mess with that...

i searched, but only found things pertaining to 22r's.


thanks!
ttyl.

langzaiguy

Does it do it with the A/C off?

Jay351

Uplugged TPS isnt doing any good. Make sure its hooked up and working correctly.

A new fuel filter never hurt anything I need to do mine but im scared of the rusty lines

abecedarian

considering there is a switch in the tps that tells the ecu you're throttle is closed, if the tps isn't hooked up how's the ecu going to know you're at idle?
the fluctuation is probably being caused the ecu trying to keep the mixture correct using the O2 sensor.

Crawdad

With the TPS unplugged, of course you're going to have idle issues. The ECU has no idea what's happening with the throttle, and has no idea what it's supposed to be doing. Your ECU is having to rely completely on the AFM and the O2 sensors to figure out what sort of fuel mixture it needs to be making.

Edit: but replace your fuel filter anyway, mine was nasty at 180k.