Hey Everyone,
Ive recently purchased a 2000 Discovery 2. I really wish I would have found this forum before because I wouldn't be in the situation I am in now. So before I get the "you should have never done that" posts... I know.

I found this Disco on craigslist went to check it out and test drove it did a few good checks on everything and went over some of the problems it was having with the PO. I thought to my self I can fix it easily new plugs, coil wires, and coil pack and it'll be good as new.

I drove the car for the first week having the occasional misfire and that weekend I put in new plugs/coils/wires/battery and alternator. Same problem so I got in touch with a reputable Land Rover mechanic here in Sarasota FL and to make a long story short after a week he could not find the problem.

This is what we have checked:
Spark to plugs (Good)
Fuel plugs (Good)
O2 Sensors (Good)
Cats (Good and not clogged)
Compression and Leak Down test (All good but 1 cylinder was at 125)
MAF (Good)
Gaskets (Replaced Plenum Intake and TB)
Grounds to engine block (Replaced)

There may be more but this is what I can think of off the top of my head.

Now a little back story on the vehicle that I am now finding out. The car was from Nevada before the PO bought it and only had it for a few months. After going through everything I found the engine had been replaced with a used engine. The ECU has been replace with a Non SAI ECU where as I have SAI. I figured this must have been programed in when they did the swap as I have no code for the SAI. With this I am at a stand still of what to do next and I'm hoping some of you guys with LR experience can shed some light on what Im dealing with here. (Frankenstein Disco)

I think Im going to take the car to another shop that can program ECUs and have it re-flashed to make sure this is not of any cause. I am aware I could have bent or sticky valves but my mechanic thinks other wise due to the misfires all on one bank. I don't want to rule this out though, along with maybe a worn cam?

Here are the codes I got shortly after I bought the rover:

P0447 (EVAP circuit open)
P1590 (?)
P0453 (EVAP Switch High)
P0130 (O2 Sensor)
P1300 (Misfires)
P0303
P0305
P0300
P0307
P0301

Thanks for reading and any input, Im looking forward to seeing what you guys think.

 

1. What codes are you getting now (not shortly after you bought it)?
2. I don't think (but I'm not completely sure) you can re-flash the ECM. I think you'll need one from an SAI truck. Hit up Paul Grant or Abran on this forum. They're both great guys and will steer you correctly.

 

Hey thanks for the response.
After replacing everything I mentioned above I'm still getting
P0300
P0301
P0303
P0305
P0307
P1300
This is only after driving it for about 5 miles and no more. It is currently in the shop and I'm planning on picking it back up tomorrow and ill pull the codes once I get home to confirm these are the remaining codes.

Ill send one of them a message and see what they think about a re-flash and if it could be the underlying cause of the misfires.

Thanks again!

 

I think this just got easier, and I don't think you need a new ECM. Just change the pre-cat, upstream oxygen sensor for Bank 1.

Others have argued on this forum that a bad O2 sensor cannot cause misfires but my personal experience refutes that.

Three years ago last month I had misfires on all the even-numbered cylinders. The probability that four plug wires, four spark plugs, or both coils went bad simultaneously was too low to make any sense. So what did all four cylinders have in common? The only answer was the O2 sensor. I changed it and all was good.

Interestingly, I wasn't getting any codes typically associated with a bad O2 sensor yet changing it cured the misfires.

If you want to test this diagnosis swap the O2 sensors side-to-side, clear the codes, and see if the problem moves to Bank 2.

I know you said you checked the O2 sensors and they were "good," but how did you check them?

 

02s were checked by my mechanic by removing them and running the engine. I'm not 100% sure of the prosess he used to determine that they were responding correctly but I just trusted him that he was able to rule them out. I might as well replace them as I already bought 2 from Walker 02 sensors. After reading through some forums i saw Walker was the best way to go with O2s over Bosch. It would be awesome if that is the problem. I should be getting the rover back today so I'll try changing the 02s tonight and report back.

If that's not the problem I don't know where to turn other than the ECU. After seeing it was replaced in 2015 it has me thinking something wasn't done correctly and that's the worst part about this car. I have very few information on the history of it. It was obviously taken care of to a point. New OME suspension and anything that has been replaced has been done with quality parts specked by Land Rover.

 

This is so much fun!!!
Got it back from the shop today my mechanic told me to drive it around and maybe run some Seafoam or something similar through it. Thinks the valves are gummed up.

So driving home from the shop, no misfires and its driving good. Next think I know it shuts off in the middle of the road and won't start again. I get the car into the median and call my mechanic after looking the engine over we both agree its the CPS. So I wait and it starts up 15min later. One block from the house. Same thing, dies and have to wait 15 min and starts back up. After it starts back up, the idle is very rough and I'm getting the flashing CEL.
Back home now just ordered a CPS which will be here Thursday. Might throw in the O2 sensor if the engine cools down by dark.

 

Skip the O2 sensor and just throw in one of these ... you'll be all set!

 

I told myself I knew what I was getting into when I bought it... I was wrong. I don't know that Ill even be able to afford the grenade by the end of the week...

 

Don't pull the pin yet... you'll get it sorted. Especially if it's a CPS or O2 sensor. We've all been there, probably more often than necessary.

Although I think you might be missing the most important tool/step to diagnose and repair a ROVER...... TEQUILA! Always start there 1st.

 

Ill be putting an order in for a crate of tequila after I do this O2 swap, I think you're onto something...

Ill keep at it until I figure it out... Even though it was expensive to have a mechanic look it over and do some test It was probably worth it as at least I feel Im heading in the right direction.