Hi my 2003 st170 has started going sluggish when u go and hold a steady speed at low reves bout 2-3 thousand revs.Also when sitting idling at lights it starts 2 sound as if its going 2 stall.Any 1 got any ideas on what it could be?Ive checked codes and not saying anything.

 

Stuck/Sticking throttle plate, blocked air filter, low fuel pressure?

Engine management light on?

 

No eml on.By the way ur talking there it could be a number of things.

 

Plug it in see if any codes are stored. It won't always bring the eml on.

 

The only codes that are stored is the fuel rail pressure sensor and oxegen sensor bank 1 both replaced with brand new 1s bout 2 months ago.