I recently rebuilt a salvage LR3. It previously overheated and somehow burned out the ecu in the process as well. Bought a new ECU from LR Direct in the UK, Pulled the heads and had them skimmed, installed a LS-300 insert head kit, bought new coils and plugs, installed new cam chain guides, everything looked good. flushed out everything but I have this nagging code and the rover is running on 1/2 power. I know the code means that there is a failure in the primary/secondary circuit and I think I may have a short in the wiring harness but I am having a hard time understanding where to look exactly. Does the last 3 in P0353 mean the issue is with the #3 coil? From what I can tell, the #3 coil is located at cylinder #6 or is it cylinder #3? If I knew this for sure then while swaping plugs and coils I would feel confident I am working toward a goal. As of now, I'm stuck and not sure of anything. I would rather rebuild the engine twice than deal with this stuff.

 

It was very messy with cylinder numbering, however for diagnostics(anything involving a fault code) it is based on actual cylinder number(not coil number) which is odd/even split, bank 1 being passengers side(for LHD vehicles) So, second back on the RH side of the engine(when sitting in the vehicle)

I would start by swapping the front two coils on that side, and seeing if the fault follows, along with a visual inspection of wiring. If the fault follows the coil(turns to a 351) toss a new coil on it.

 

Thanks so much Roverguy7! Geez, I thought 1-4 was running down the right bank, not split. It is confusing! So I have been messing with #5 instead of #3. I did pull the loom off that bank and inspected the wires. Although the loom looked horrible the wires looked new. Also checked the voltage, 12.5 on the lead and 5.5 from the ecu, but I cant remember if I checked that cylinder. I'll follow your advice on switching the coils first and see how it goes. Probably check the compression next and the injectors. I would be surprised if I have low compression but I may have clogged cats. Since this was an overheated, perhaps the injector is experiencing a mechanical failure? The valves looked great and the engine had only 80K when I got her so I did not ask the machine shop to do a valve job. Installing the LS 300 kit threw a million chips around and I forgot to cover the cats, I blew them out and vacuumed but I thought it would worth a shot. But that leads me back to the code. A P0353 is specific to the coil correct? A clogged fuel injector would throw a miss fire code, which I have for that cylinder, but it would not cause a 350 series code?

Thanks again!

 

Exactly. Sort out the 353 fault, and see what happens with the 303. Might want to pull the #3 plug to make sure it's not flooded from not having spark when swapping the coils, just to save the headache of still having a 303 when everything is ok with it.

 

BINGO! I had an extra coil, made the swap and that was it. I did pull the plug before the swap and it was wet with gas so I knew I was on the right path thanks to you! Cleared the codes and nothing came back.

Thanks Roverguy!