My service engine soon light came on the other day and my truck now has a very rough idle. I took it to my mechanic and he got 2 codes. P0150 and P0174. I always run good premium gas and just replaced the plugs and wires about 2 month ago. Bosch Plugs. Land Rover Wires. My truck is a 2002 Disco II with 71,000 miles. Any help would be appreciated.

 

If I knew what those codes meant maybe I could help, but I dont know them, somebody else does and they will chip in.

 

P0150
Generic
O2 Circuit (Bank 2, Sensor 1)





P0174
Generic
System Too Lean (Bank 2)

Time for a set of O2 sensors. I think rover connection has the best price right now...Don't go for the cheap generic one's..

 

Thought it may be the O2 sensors. I'll be replacing all of them. I'm pretty mechanically inclined but never did O2's before. Is this something I can do myself?

 

Of course you can do them, but they may be stuck. Best to purchase a special socket designed for taking them out.

 

This one I know, it is called a O2 removal tool. They come in different sizes. No I dont know what size yours is, sorry. Buy it at AutoZone or Sears.

 

soak them with PB Blaster too.....

 

..when its cold.

 

theyre 22mm, easy to do, but the connectors can be a pain to get off and back on if youre on your back... however it might not be the sensors... since you also have the lean code theres a good chance that your o2 code is just a plausibility fault and youre actually looking at a vacuum leak on your rh cylinder bank. you might be wasting a good amount of money on some sensors if thats not your issue. try replacing the upstream sensor on the rh side, if it fixes it its your issue then go ahead for the rest. but check your enigne for air leaks. look at right where your rubber breather tube goes on to your upper intake on the rh side(pass side) theres a little nipple, you should either have a cap on it or a plastic vacuum harness that goes to it. also a large exhaust leak can cause this, and in the end spark plugs or arcing wires that are causing your fuel to not burn all the way will give you the same lean code. personally i would be looking more towards the lean code then the o2 code