By JA on Tuesday, June 26, 2001 - 04:20 am: Edit

Hi guys, it was late and dark last night & I decided to wait til today. Anyway, I'm replacing the rear two 02 sensors in my 96 Disco. Only investigating I've done thus far as to proximity is the Haynes manual. Guess what -- no hints.

Anyway, in the event they're not obvious, or that they're easily confusable with the fronts, any tips as to exact location of the rear 02 Sensors? (pictures woul be nice).
Thanks!
-JA

By Ron on Tuesday, June 26, 2001 - 04:21 am: Edit

Fronts in front of cats rears behind cats

Ron

By JA on Tuesday, June 26, 2001 - 04:36 am: Edit

Ron, the Haynes suggested they were ALL between the exhaust manifold and the catalytic converter. You're telling me that the Haynes is flat out wrong and that their going to be probably right around the xfer case AFTER the Cats?
-JA

By Ron on Tuesday, June 26, 2001 - 04:42 am: Edit

Then how do I get faults after the cats/ a bad cats messing up the o2 sensors? I will double check tonight, but I could have sworn they were after the cats. Earlier trucks had two O2 sensors in front. If you look in the engine bay you can see the front ones. The rear ones are by the T-case, I think behind the cats. In any case it is pretty obvious when you are under there.

Cheers
Ron

By Jeff Bieler (Mrbieler) on Tuesday, June 26, 2001 - 04:52 am: Edit

1997 SD. Two Lambda/02 sensors just forward (engine side) of the each cat. Pretty easy to get to.

Sometimes having the Mac next to the door leading to the driveway can be helpful...

By JA on Tuesday, June 26, 2001 - 04:55 am: Edit

Hmm. So now I'm vexed. Ron, you have a good point, how do you know if the cats are junked if all 02 sensors preceed them. And why need two sets between Exhaust manifold and cats. Then again, Jeff states that they ARE in fact before the Cats.
Damn.

By Jeff Bieler (Mrbieler) on Tuesday, June 26, 2001 - 05:02 am: Edit

Realising that something is amiss, our intrepid hero jumps out the side door, slides beneath his truck, smacks his head against and frame rail and confirms that yes, in fact, there are 4 sensors.

Two are just in front of the cats. Two are behind the cats on each side of the transmission.

By Ron on Tuesday, June 26, 2001 - 05:04 am: Edit

Two are just in front of the cats. Two are behind the cats on each side of the transmission.

Haynes 0

Ron 1


Ron

Thanks Jeff

By JA on Tuesday, June 26, 2001 - 05:09 am: Edit

That's freaking funny. Hopefully I'll still be laughing and not cursing. From your swift movement, it would seem these things are not only accessible, but completely VISIBLE! Wow, so I'll grab two beers, a handful of open-ends, and a pair of plyers, and be at the driving range in a half hour thereafter.
You guys are making me lazy. I guess I too could have looked. Thanks Ron. Haynes "0" is an understatement. I love phrases like "use specialised tool" or "tighten to proper torque setting." Thanks Haynes.

By Ron on Tuesday, June 26, 2001 - 05:13 am: Edit

Actually one of the rear ones was changed on our disco about 2 months ago. I did not do it. Alyssa did, it took about 5 minutes. PS don't overtighten it, something bad happens if you do. think it was a 19mm or 17mm wrench.

Ron

By Jeff Bieler (Mrbieler) on Tuesday, June 26, 2001 - 05:15 am: Edit

Yes, but they were only visible after I tripped over the car seat my wife left in the doorway and had banged my head against the frame. They may have been 4 sensors, but I think I was seeing two of everything at that point.

The front ones will require a little bit of contortion, but the rear two are no problem. By specialised tool, I assume they mean a wrench versus your teeth.

By Stephen on Tuesday, June 26, 2001 - 05:17 am: Edit

or a slotted socket.

By JA on Tuesday, June 26, 2001 - 05:21 am: Edit

Hey, I'm a sucker. I bought the book. I guess that makes me the moron, not Haynes. It could have been full of comics for all they care.
Land Rover Peabody (MA) charges about $500 for the job!
HA HA HA!!!! That's in my pocket.
JA

By Ron on Tuesday, June 26, 2001 - 05:27 am: Edit

In all fairness to haynes earlier trucks have only 2 (not 4) and they are in front of the cats where the front ones are on 96 and up. 90 bucks from Nathan and 5minutes of your life or 500 from LR and a day at the dealer, humm let me think ... you are definately not the moron.

Ron

The rear o2 sensors are the bain of my existance.

By JA on Tuesday, June 26, 2001 - 05:31 am: Edit

Actually, its $90 x 2 = $180
Versus
$500 x 2 = $1,000
why are they your bain?

By Ron on Tuesday, June 26, 2001 - 05:41 am: Edit

Because they set off the check engine light every 60 days or so (although since being replaced no major issues have developed) and I think they are the ones that are telling the engine to run rich which it turn carbon fouls it (hypothesis I know nothing of how the GEMS system works). And since they are down stream of the cats I can't hollow out the cats like I can on my RR. Overall they are just a bain.

Ron

PS I assumed only one was bad.

By Bill Bettridge (Billb) on Tuesday, June 26, 2001 - 09:46 am: Edit

Ron - funny thing - John B also has those "flow-through" cats on his 88 RR - makes it sound great - gee wonder how they got that way?