It pulses from about 700 to 1400, it mostly does it when in park. When it is in drive it mellows out some and when the a/c is on its hardly noticable. what it feels like is the iacv closes to bring the idle down and it almost chokes it out so it opens a little and it revs up then tries to bring it back down and chokes it again just cycling like that. When I put a load, like the a/c, on the engine it loads it down enough for the iacv to open a little and find a happy medium. Sometimes its worse than others. I cleared the code last week and was running the a/c and the cel didn't come on for about 3 days when I turned the a/c off. I can't help but think there is a physical reason that won't let the iacv do its job, like my base idle speed or timing or a vac leak, but I can't find any vac leaks and its hard to set timing and base idle speed when you can't get the truck to idle smooth.

 

look what I found in the rave,

Vehicle speed sensor

The vehicle speed sensor is located on the side of the
Transfer box adjacent to the parking brake. The
sensor provides road speed data to the ECM. The
ECM in turn detects vehicle movement from the road
speed input and ensures that idle air control mode is
disengaged. Should the vehicle speed sensor fail in

service the ECM idle air control would become erratic.

 

Tweak you may have just solved another common problem.
I was not away of this, I was only aware of the "stalling" while driving problem with the VSS.
Are you going to replace yours?

 

What about the speedo? Is it acting up?

 

I though this was possible, But I searched the whole rave and found nothing. I really hope this is true. I'll replace my asap with one from a junk yard.

However wouldn't the speedometer be funny?

 

I cut and pasted it strait from the rave so it must be true, my speedo does run about 6 mph slow and my cruise control doesn't work( which I've traced back to either cruise ecu or vss signal). I want to change it but I'm waiting to win the lotto, anyone have an extra or want to let me try theirs to see if it fixes it.

 

I was reading through the overveiw of the fuel system and there it was, I remember reading it before but I guess I disregaurded it cause I thought "how can it affect idle when the car isn't moving", but when it isn't sending a signal the truck knows to go into "idle mode". Now to pull $110 bucks out my butt. It is going to have to wait cause I am going to the mountains with my dad on our motorcycles this thurs, all my cash is going to that. I'll post some picks if you guys are interested.

 

Of course we want pics.

 

Its not rovers but surely you guys have an apperciation for cool motorcycles.

 

Cool Motorcycles? They aren't British Bikes are they?