The continuous running cooling fans are a clue here , this is a sign of the ecm not seeing the correct coolant temp reading and running fans as safety default
Coolant Temp sensors ..... is the ecm data block showing correct temp ?
Does it have two temp sensors ...one in engine block somewhere near cyl heads usually ,and maybe radiator outlet temp aswell ?
The lamda codes of lean mixture is strange like you say , are the pre cat lamdas 4 wire or 5 wire wide band with a red or pink wire on the 5 wire type ?
In data blocks for lamdas does it have a block called 'lamda equivalence ratio ' if it's five wire it will have , if it's 4 wire it will have a cycling voltage between 0 volts and 1 volt or 0 and 4 volts ...the cycling voltage is correct ( lamdas switching from rich to lean ) if lamda Volta sticks one way or the other it's over rich or to lean ....drive the car up the road at a steady pace and watch what these values .
Also have a look in the data that it says it's in closed loop mode , the running cooling fan default mode may keep it in a open loop situation
The running fans has to be your first port of call here , sometimes the fans control module can go faulty and put the fans on also ....you normally get codes for this though
But you donot always get codes for engine temps being massively out of range but ecm runs fans just because it does not know what the true temp is .
Last edited by Mechcanico Lee; 1st October 2016 at 09:22 PM.
|