1998 Discovery I

Newbie looking for help. My yellow check engine light has been on for over a year. OBD scanner reads Code P1193 (Open circuit in O2 sensor heater circuit). Tried resetting error codes a couple of times, but same code and check engine light comes back on after a few drive cycles.

After reading previous posts Ichecked the harness connections at the O2 sensors and they appeared to be very clean on the inside after disconnecting them. Engine runs good with 130,000 miles. Unfortuantly, I have been using only 89 octane.

I know I should replace all 4 O2 sensors, but before I spend $500 on them is there anything else I can do?

Thanks!

 

It may be that you have frayed wiring on the back two. The placement of these sensors is questionable so look at the wires closely from the sensor to their respective plug.

Also, I've read a lot about this problem and with personal experience on my disco can attest that the lifespan of these sensors is not what you'd think. Anytime after 100k the sensors can be bad. Don't be fooled...the dealer cannot tell which one is bad any more than you can even with their testbook computer.

If you're sensors are not working you're experiencing some pretty bad gas maileage as the engine is forcing more fuel through the system than it needs. Your payback may be pretty quick.

The dealer would say you need a special wrench to replace the sensor on the driver's side manifold (before the catalytic) but I just cut down a 17mm wrench and it worked fine...

Hope this helps...

 

There is nothing that you can do other than replace them.

 

And after a year of driving using the wrong gas and bad O2's you may need a valve job in the near future too.

 

Thanks for the reply's guy's!

I will order a set of O2 sensors from Atlantic Britishand will check for frayed wiring first. On there website they all appear to be the same part number.

However,you say the Drivers side pre-cat O2 sensorrequires a different size wrench. Would there be a different part number just for that specific sensor?

Thanks again

 

By different size wrench he just means that there is no room to turn a wrench, it is to long. The "nut" is the same size as the rest.

 

Got it! Sure is nice having your help!

 

No problem, that is why we are hear.

 

If you want to save a little money and get the right 02's, go to Rover Connection, their's are just under $100 a piece.

 

Nice! That sounds alot better than $129 I was preparing myself to pay!