My sister has a 2001 Discovery II about 135k miles. Well maintained for the extent of its life.

Last week the dash lite up, she is showing the following codes:
P0150, O2 Sensor Cycle Fault B side (2?) Upstream of Cat
P0159, O2 Sensor Slow Response BAnk B (2?) Downstream of Cat
P0174, O2 Sensor Systme too lean Bank B (2?)
P1170, Front Heated O2 no inversion
P1174, Fuel Trim Adaptive Inactive, System too rich Bank 2

So I get the idea it might be a O2 issue on Bank B/2, is that right? I also saw that it might have to do with a MAF. Any ideas? It seems to be running failrly well inspite of all of the codes. Thanks Phil

 

At 135K, I would say to change them all.

 

That's not too bad they are all just O2 codes. Change all 4 and be happy it is an easy fix.

 

So my sister took her truck into an independant shop today. Turns out she needs head gaskets and a radiator. Got a good estimate at $1400 and $2000 to do head gaskets, plugs, wires, radiator, hoses. What a bummer, the truck is worth about $4000 running and it needs $2000 worth of work. Thanks Phil

 

How did they come up with that list of repairs? Plugs, wires and hoses may be a good idea at your mileage (and easy to do yourself) if they haven't been done in a long time, but radiator and headgaskets? Did they pressure test it? Did they expect those repairs to fix your codes? I doubt it's the MAF since to don't have the typical codes and you would have codes for both banks is it was.

 

I would not go back to that shop. Do the O2 sensors yourself. Does her truck have a coolant leak?

 

my sister and her truck are in Salt Lake City, I am in San Diego. 23 degrees in SLC, 73 degrees down here, how I don't envy you guys that live in the cold states when it comes to do it yourself auto repairs! Brrrrrrr. The shop is very well thought of. My sister has used them for years on her two classics. Evidently they did all the diagnostics and came up with the probable issues. She has been loosing radiator fluid and the truck has gotten into the red on the gauge a couple of times. That worries me. It is a very nice truck with all of the options, including ACE but she is starting to get to a point of no return. Dang, if you need to pay for a head gasket job you really start pushing up against whether to get a new truck.

On a positive note, a good friend of mine moved from SD to SLC last summer. He had seen all of the fun that I was having working on our two discoverys. He just picked up a 97 with about 100k miles on it for $600, needed a head gasket. He oredered the parts, did it himself, is now into his truck $900 and absolutley loves it. Another convert. I should be a southern minister! All the best. Phil

 

Well $1400 is not that bad if it includes everything to do a tuneup, radiator (should just need to get re-cored), plus the O2 sensor and the purge system problem.