check engine light just came on... I'm getting two codes P0174 (system lean bank 2) and P1158. (seems a sensor could not switch to lean? and ran to rich?)

im fairly new too OBDII disco's so im not sure were to begin. im thinking maybe its a problem with plugs/wires. im really hoping i don't have to replace o2 sensors!!!

most people with bad o2 sensors . have more codes then these 2.

any input?

just spent butt loads of money on some fox's

its '97 disco XD with 4.6

 

how old are your wires and plugs ? to me the codes indicate a bad o2 on that side.....how old are the o2's ? & how many miles on the truck.

secondly were the fox'es 4-legged, 2-legged, or mechanical ?

 

around 103K miles on the truck not sure if they are the original o2's. every other vehicle Ive seen with bad o2's seem to get misfire codes and other codes relating to the sensors...

there were a few start ups were the truck was sitting in 120+ desert heat were it took a while for the truck to start and it had really low idle but that was maybe 1-2 times it usually starts instantly. the idle was set to low to begin with so i brought it back up to specs.

im wondering if the codes got tripped from the odd starting issue. i dosnt feel like the truck is running rough or dogish, no real smell in the exhaust and im getting roughly same crappy MPG as it usually gets.



on the second note the foxes are the remote resi' 2.0 12" and i could only afford the rears for now haha

 

hehe love the cooking set up. well o2 sensors are very expensive and $61 each and they will go in the next 30k if you havn't done then do them now. They take about 10 mins each. just make sure you have the right o2 sensor for the right emissions system.

 

thanks, as far as the 02 sensors i should only have to replace the fronts right? i think the post cat o2's are just to see if the cats are operating, the front ones should deal with all the air/fuel issues....

maybe someone on here can confirm..... Mike...spike....anyone...

 

That is correct. The rear O2's only confirm the cats are working. Everything else is based off the front 2. They should be replaced in pairs though if possible.

 

What he said.
www.Amazon.com has the best price on O2's for DI's.

 

Everything I know about O2's I learned from Spike. LOL. Really though I have seen him say this a couple times the last few days on some other threads. So credit has to go to Spike.

 

I have only recently found out this info.
I have been looking for O2's for my wifes car and was going to replace both the front and rear (it only has 2) but after doing half a days research on how they work, what they do, blah blah blah you only ever need to replace the front ones unless you are getting a code for the rears.
Even then if you can find them there are "dummy" or "O2 simulator" for the rears that fool the ECU into thinking the cats are good even though they are not or are gone altogether.
So lets say you want to rebuild your engine but you still need the ecu for it but you are running straight pipes all the way back and it is for off road use only.
You can remove the cats, install the dummy's and be perfectly fine, the ECU will not know the difference.
So far I can not find them for Rovers, but I have not looked very hard...yet.
they are common for Chevy's and Ford's and can be bought at Summit Racing.
Anyway, more info than you guys wanted and totally not relevant to the original post.

 

Yeah I found out from hours of browsing the shop manual haha a lot more comforting knowing its only 2 and they are pretty cheap. I had the two fake o2's on my mustang post cat hahaha I bet there's a law against in cali but owell maybe someone should find some that fit rovers