I have a 96 Discovery with around 116k miles. The check engine light currently came back on (after resetting it to see if the same code would appear) and is showing P0125 Mod $E8 Closed Loop Fuel Ctrl Insufficient Coolant Temp. Can anybody help me diognose this problem? I wasn't sure if it had anything to do with the O2 sensors or what. I still have the scan tool I'm borrowing and it will read things like the O2 sensors and whatnot. I also have a sound coming from the cats that may be the insides coming loose...would this possibly contribute to the problem? Thank you in advance for any help. This is my first Rover and I'm loving it so far...all except the fuel mileage...ha.

 

Sounds like you are looseing your cats, probably been running too rich or a coolant leak. You need to find out what killed the cats before you replace them.
As for the O2's, at your mileage they are pretty warn out, but not causing your problems.
As for your fault code, sounds like you have a failed coolant temp sensor which is causing the engine to run way too rich, probably would be good to replace it for starters.
Mike

 

Is there a seperate coolant sensor for the gauge, because it seems to be reading fine? Didn't know if there is a seperate one for the computer. What are normal readings for o2 sensors when at idle? Also could my engine code have anything to do with the evap system? Thanks again.

 

I don't believe your fault code has any thing to do with your evap system. I don't know what the O2 readings should be, but at your mileage they are most likely not as responsive as when they were new nad you performance will be effected because of that. As for your question regarding the temp sensor, I don't know if you have a separate one for the guage or not, but to me, that code would indicate your ECU is not getting a good temp. signal which is not allowing your system to go into closed loop, hence you are running very rich which is probably why your cats have melted down.
Mike

 

I'm going to start with the sensor and go from there. Should have that in on Thursday.