high emissions

[big geoff]

Hi had a pre mot today filed on high emissions after 2nd fast idle 7.3 and lambda reading outside the limits any ideas please

[big geoff]

just removed the two lambda sensors one was black and sooty and the other was whiteish hope this helps for your replys

[dogbucket]

I am guessing the sooty lambda is faulty resulting in that bank overfueling, although I thought if that was the case it would fuel both banks based on the one working sensor. Maybe clean them up then swap them around and see if the soot follows?

paging Blitz..

[blitzracing]

If a probe fails the ECU cant tweek the mixture acurately, and its one probe per bank, so each side is set completely independantly. You can test the probes with a test meter jammed down the back of the connector between the black (+ve) and white (earth) wires. With the engine warm the voltage should constantly switch between .2 and .7 volts DC at about 3/4 second intervals (not regular). This does sound like probe failure, as its likely one output is low. The best place to get them is Ebay in the USA. Search for Global automotive lambda. You will find the Range Rover ones at about £14 if you dont mind a few days wait.

Mark

[big geoff]

thanks guys i have ordered two new ones regards geoff