ecu problem!

[mikeyc88]

right on my vtr mk2 the ecu light came on a while back, error code p0420 catilyst effiency below threshold was the fault. It also juddered when in low revs when driving So i replaced top lamda sensor then ereased code. Now it back on again! Cat seems fine. Also my fan comes on when turn ignition off most times for around 5minutes.

[Macnme]

check for leaks on the joints of the down pipe as the lamda sensor needs suficient presure to work correctly an air leake would course loss of presure an give a faulse reading making the ecu think the cat aint working ..... possibly lol just pure speculation without seeing the car tho :S

[Macnme]

fan could just be due to the hot weather we've had lately ???? of check ya coolent level !

[mikeyc88]

ok wil do, and coolant fine, could it be the engine coolant temp sensor that affecting it?

[Macnme]

the fan yes but not the cat an engine management light .....