Hello,

I have a 1996 Land Rover Discovery. Just went to get it smogged. It passed the emissions fine but I failed because some codes showed up. p1194-oxygen sensor heater circuit high resistance, downstream sensors---p1191-oxygen sensor heater circuit open circuit, donstream sensor---p0300-misfire??????
Can anyone tell me what these mean and how to fix them? Thanks. any help is appreciated.

 

get new o2 sensors, plugs, and plug wires

 

How many miles?

I agree with the last post.

 

I have 146,000 miles on it. It runs good though! Just need to get those codes clear! Where can I clear the codes?

 

clear them and they WILL come back almost instantly... you must repair the underlying problem for them to be "cleared"

 

oh yea, and stop using regular 87 octane fuel

 

Your 02 sensors do need to be changed out, once that is done then you can address the 0300 misfire code which could be from cheap gas, bad plugs and or wires and carbon build up.