Quote:

Strong concetration of bg44k fuel cleaner will help you, it did solved constant missfire codes on my 4.4 ajv8

So mechanic checked the cats and sees nothing wrong with them apparently.

Misfires on every cylinder however mostly across 1357 which apparently isn't on the same bank on the Supercharged.

Banks are allegedly split like this....

1234
5678

Only misfires at idle according to live data collected.

Sheesh.  Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Banks are 1357
2468

Dingg is correct the mechanic is quoting the BMW order.

If you put your foot flat down with the windows open do the cats stink Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Thanks Gents for confirming the cylinder pattern. I can't thrash engine atm after engine rebuild for a bit. Apparently. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Have you checked the fuel pressure?
This can be measured by the fuel pressure sensor via the OBD2.
A good reference: https://www.rangerovers.net/threads/4-2-li...ue.345359/

So misfires only on 1357 on one bank now after sorting air leaks on engine. However I have had it confirmed the valve clearance is further out of tolerance after engine rebuild. So also have had trouble when starting in colder weather which also relates to valve clearance issues again apparently.

Fuel pressure via ODB2 tool is all good. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Have you been in contact with the place that rebuilt it?

Dare I ask if it’s worse now that prior to the rebuild? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Yes but they won't offer a resolution to valve clearances.

I tried swapping plugs over and coil packs but still the same so surely its internals. So I will update when I have more info. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

If you hired them to do a specific job and it’s still not done surely you have a case for the small
Claims court if it eventually came down to it…

Did they reshim it or change the buckets? Guessing both banks? What did you pay if you don’t mind me asking, Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Could these misfires be caused by valve clearances being way out of tolerance? Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Have you checked compression?

This guy here had problems with his car misfiring when cold. He checked compression and found he had issues and then moved on to check his valve clearances from there and that was when he found problems.

https://www.lpgforum.co.uk/viewtopic.php?t=16575

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

The rebuilders said compression was fine after the rebuild as it's one of the tests they check after. However after requesting said data they seem to have misplaced the testing data somehow.

Interesting comment though. I will remember that thank you. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

If the valve clearances aren’t set properly then I’d hazard a guess at compression not being right either

I’m hoping that mine has been cured by fixing an air leak but won’t know for sure until it’s back together as mine misses when cold too.

The guy in that thread reckons sorting his valve seats himself cost him £4K so I’m praying it’s nothing sinister on mine at the moment.

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2007 Range Rover Supercharged in Java Black with Ivory Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior