I've got an 03 discovery. Check engine light comes on and goes off. Scan said there was a stored code for downstream 02 sensor but also told me there was a number 6 misfire. I changed the plugs. Light came back on. Rover's mpg's has gotten worse. Did not change wires yet, just bought them. At idle if feels like there is a slight miss. Throttle response on my 84 blazer seems better. If you punch it real quick and let up it dang near wont move. Anyone have any insight as to problems that have plagued the discovery other than oil leaks, etc., etc. Problem is that I have a warranty which includes oxygen sensors but not wires. I have a leaky valve cover gasket so I was going to have them repair that and while intake manifold is off have them change the wires (plugs were bad enough to change). Thanks

 

Do you still have a check engine light on, if so what are the codes?
How many miles on your engine?

 

1. OBD-II gave code of P0455 Evap Emission Control Leak?

2. I got 290 miles on 22 gallons (87)= 13.18 mpg. Is that normal? I run it harder than most people on the road would but, then again I do with all my vehicles. Rover has new free flow muffler, k&n just got cleaned, fuel inj run through previous tank, new plugs, etc. Wires are in the mail.

3. Do you have to take off the intake manifold to change the wires on an 03 discovery? Any tips? I guess LR was thinking that child labor would be cheaper when they decided to place the plugs & wires in a configuration only a 4 year old could work with

thanks

 

Its the damn gas cap. Its been lose as every once in a while I would smell gas, pop the door and retighten the cap. You guys know of a good place to get another one. I looked at the gasket inside and it looks fine.

 

You're getting good mileage for a 2003. Have you read all the hype on K&N filters ??? if not do a search, its worth it.