Okay so I can't figure this out.I just installeda new "Y" pipe, 4 new O2 sensors (about amonth ago), Due to a P0420 code.I Logged about 300-400 miles after the install. Everythingafter the installation wasgreat, code cleared, gas milage went back upand my Disco just passed PA state inspection last weekend w/o any issues (The machanic even said"that's one d$#m cleanLand rover!").

This past weekend I drove from Philly to Wash. DC. (no trailer on the way down). On the way back up I wastowing a uhaul 5x8 closedtrailer with a futon and chair in it. Half way home my checkEngine lightcame on. The codes that are back........P0420 and now P0430. I haven't clearned the codes yet. Also, I use only 93 octane.

Any thoughts out there?

98 dico w/120,000. (just turned on the trip!)

 

You need plugs and wires.

Thats is where I would have started.
When ever a LR needs a tune up it throws O2 codes.

 

I did that way before the CAT's. I did the Magnacore and Bosch Plat's 4's.

 

Ok good. So many people spend so much money on other things when it is as simple as a tune up.

So you are getting codes for bad cats...but you have new ones...maybe a vacum leak...I need to sleep on this one.

 

I've done all of my own work (alot of work), and I always try to start with the small stuff first. But this ones got me too. I haven't gotten under there yet to see if I have any pipe leaks.But I find it odd that under a slight load It thru the codes. I need to sleep on it too.

thanks for the help and sleep tight, between my rave cd and you guys here at Landroverforumsit's help me thruall of myfixes.

 

If I had those codes, first thing I would do is pull a few plugs and look for excess richness, then check for any major vacuum leaks.
You could try using a good additive lie B&G's 44K to try and clean out the cats, this would only be a temp fix though. How about oilo, are you having to add much, if so, you could have a intake manifold gasket that has failed and it it is allow alot of oil to be burned off which could overlaod the cats.
Let us know what you find.

 

Could be an exhaust leak between the cat and the downstream O2 sensor or the upstream and downstream O2 sensor.

 

The Cat's are brand new, and not a remanu (same goes for the 02's -Not a universal- I buy all parts from ABritish) complete "y" w/cats. I typically use Seafoam in the tank once a month. As for the oil I don't need to add any on a daily basis or anything (I did check before and after my drive, all was well). I use a synthic blend oil. I also have not had to add any anti-freeze. The exhaust runs alittle white when I start her up but after a few miles it runs clean. As for the leaks, I can't hear anything out of the norm. However I will check once I get home tonight or tomorow morn and do a cold start. (I'm upin the Poconos right now for faily buisness- Took the Accord this time).

 

Okay guys I'm back,

I had the Disco sit for a few days before I got to look at it last night. Here's the findings. In order before starting, this is what I checked and the result:
1. Oil level- right in the middle of the marks
2. Sp.Plugs- I pulled (all)- All Are the typical Light grayish color, Nothing out of the norm.
3. New "Y" exhaust Assm connections points-top connections at the downpipe gaskets areboth tight. the connection between the front section and the rear section was also tight....HOWEVER.... at this connection there wasa heavy amount of condensationcompletly around this connection and around first weld at the intake side of the resonator.

After start:

I started the Disco and felt around all the exhaust connections (Top side and bottom) and couldn't feel any leaks. Although at the front to rear connection, the condensation was (i think) boiling away.the boiling appeared to be coming through the connection. Maybe this is the source of the leak?

FYI- when i did the exhaust replacement, I did not install the "Olive" because the new"Y" and (old "Y") did not need the "olive" because the end was flanged and it didn't fit. Do I need to Install this?

Well where do I go now Guys....

Oh yeah, After sliding under my disco, I also saw my rear oil seal on the diff is leaking. In the Rave it shows special tools to pull the seal and bearing. Can i do the job with a gear puller? do I need to pull the Bearing?

 

.......Is there Anybody Out there?