Rough idle & cruise control??? Need help

[rossbaxt]

Just picked up
a 09 rtx a couple of days ago maby have put 20 kms on it. Motor is stock.

First issue- on cold start up the idle is fine, once the sled starts warming up or at normal operating temps it idles around 1600rpm then will slowly drop to 1000-1200rpm it sounds like it’s going to stall then it will come back up to 1600rpm & it will just keep repeating this cycle.

2nd issue- start up with a cold motor, once temp light turns off I’ll start driving it.

if I’m driving at or around 4000rpm maby 20-50 kms and I let off the throttle, the sled maintains that rpm and speed as if it had cruise control. I’ll put the brakes on and force a slow down somewhere around maby 3000rpm the rpms will drop down to idle as it should...

once the sled is at normal operating temp it kinda stops doing this but it’s alsmost like there is a delay when letting off the throttle at lower-ish rpms.

At idle if I give a little throttle Brap it takes way longer for rpms to settle than my buddies nytro.
I’m assuming these two problems are related, but unsure.

ive changed plugs
Set throttle cable free play
Removed and cleaned isc and ran the diagnostic on it
Did the diagnostic on the throttle position sensor(closed was flipping between 18-19 closed & wot was good)
Tried a different crank position sensor

Anything similar happen to anyone? Any ideas or suggestions? Any info would be greatly appreciated
Thanks

 

[rossbaxt]

Oh and I was thinking about adjusting my tps sensor angle to get it down to 16(middle of the tolerance)
But I’ve read this can be tricky & could maby make it worse?
With it the reading going between 18-19 think this is something I need to worry about?

 

[Confused]

Idle air control issue?

 

[rossbaxt]

Idle air control issue?

is that the same as the idle speed control sEnsor? ( 3 screws mounted on top of the throttle bodies)
Or is there another one?

 

[grizztracks]

Two things I'd be checking:

1) Reluctor ring on the stub shaft to see if it slipped putting the crank position out of time.
2) Valve lash.

Both conditions will cause idle and/or startup issues.