O2 sensor confusion - Land Rovers Only

conrad1468 · 10-22-2009, 06:37 PM

hello,
I'm new to Land Rovers and we just purchased a 1999 Discovery Series 1. I have and engine code of P1187 and i searched and found it to be the Oxygen sensor. Now my problem is that i don't now which O2 sensor to buy.
I found on another post to look at the EVAP Family. my numbers don't match the EVAP family from that page.
XLRXE0124002 (86.130-96 PROCEDURES)
EXHAUST EMISSIONS SYSTEM
SFI/2TWC/2H02S(2)
engine Family
XLRXT04.6001

I look at the connecters and they are black. I think everything is dirty.. but on the parts websites by the year it shoudl be the gray connector.

last question. How do you even get to the connector on the oxygen sensor. i could not get my hand even close from reaching under the truck.

thank you for any info.

conrad1468 · 10-23-2009, 05:03 AM

i'm sorry but i stand corrected. the connetors are gray. i went out and took another look with a stronger flash light...

STILL.. i can't figure out how i'm going to reach the O2 connector... help anyone... The only way i'm going to reach the connector is taking off my cats...

no694terry · 10-23-2009, 03:40 PM

i just switched all mine around and they are fairly easy to get to. i did mine with a cheap 17mm wrench i found in my girlfriends garage and i did it on the street in front of her house with no jacking. yes they have grey plugs and all four are the same. to find out which one is dead you need to run the car while hooked up to a scanner and see which one has a constant voltage output, mine were stuck at 1.05 volts. if the sensor cost between 120 and 150 bucks its probably the right one. mine is also a 99 disco 1 so you have to be carefull you get the right part, a lot of parts stores think all 99's are series II. they will also ask you precat or post cat but the part numbers are the same. my local advance auto carries them for $148 i believe.

ihscouts · 10-23-2009, 04:50 PM

http://www.oxygensensors.com/catalog.php?&pkey=1356027

Disco Mike · 10-24-2009, 08:34 AM

Go to Rover Connection and check your vin against the ones they list, you will most likely need the advanced 02's and as a 99 you probably need all 4 if you are going to get the most out of your engine.

DiscoDream2 · 10-24-2009, 08:47 AM

Quote:

Originally Posted by Disco Mike

Go to Rover Connection and check your vin against the ones they list, you will most likely need the advanced 02's and as a 99 you probably need all 4 if you are going to get the most out of your engine.

Is it best to do all four on a 99 DII ? I don't need them but they are original and it would be nice to get better gas mileage and performance...

ihscouts · 10-24-2009, 10:51 AM

If you don't need them the large cost versus micro return would negate them. IMHO your tire size and ancillary equipment hanging off your DII is causing your poor mileage. Replacing your O2's would have little to no effect over the streamlined anvil cross-section of your truck. Your CEL would be litigated to not turn on for a few miles longer though.....

conrad1468 · 10-26-2009, 12:03 PM

Terry, thank you for the info. I plan on replacing my sensors the same way. except with a nicer wrench. lol..

Scout, i wish i would have saw you post earlier. i ordered the 2 front O2 sensors from Roversnorth. If i need to replace them again or the rear ones i'm going to that website. thank you.

thank you to everyone else, too.. I'm working on getting the truck to pass PA emissions. of course the previous owner disconnected the battery to hide the codes. but after driving it for awhile the check engine light came on. I suspected there was something fishy going on..

i changed my diff oil and engine oil over the weekend... it's great that i don't have to jack the truck up to do work.

have a great day everyone.

Disco Mike · 10-26-2009, 01:37 PM

Quote:

Originally Posted by DiscoDream2

Is it best to do all four on a 99 DII ? I don't need them but they are original and it would be nice to get better gas mileage and performance...

I will be clearing 110,000 miles by April and I will change all 4 02's just to get that extra punch my engine used to have. With time they gradually loose their effectiveness, and yes it costs a little to replace them, but that has always been what I recommend to my customers over the years and no one has ever complained.

conrad1468 · 10-26-2009, 07:41 PM

OK, everyone. I took out the Oxygen sensor. it was a piece of cake with a 17mm box wrench.

I don't know if this is right but the O2 sensor clip connectors are sitting on top of the trans bell housing. I had to go fishy with a hanger to get them close to ignition pack. i still can't reach it. i will have to get the wife to get her smaller hand down there to unclip it.
Is there an access panel to reach above the bell housing? or is there a trick to reach the clips?
thank you