My spark plugs were changed last year for iridium tipped and cost about £125 for the set. I believe they are NGK as well.

So fingers crossed they are the right ones. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Those iridium plugs are a pain in the butt, fit some standard ones and try again you don't need special plugs for lpg.

What issues have you had then be interested to know.

I thought you needed the iridium tipped to protect from the extra heat that lpg creates? Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

The difference in heat from lpg over petrol has no Ill effects, iridium plugs are an expensive waste and are always going wrong weve just swopped some out on my mates xk8 , not got 300 miles on them and 1 went down swopped them for standard ngk plugs all is good again.

Interesting...

It'll be interesting to see what the diags report. Thanks for the info. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

So I had diagnostics completed on the car from a well established LR engine specialist.

"All compressions were good, all over 170psi
Diagnostics have shown nothing, both banks running ok. However, we suspect that part of the reason the left bank (bank 2) was off was because all four plugs were loose (as in finger tight only) and didn’t need a socket to undo them. That may well be the cold misfire issue sorted."

Now I assume the compression psi levels are all good?

So only chains and shims to tackle. As I had confirmed the heads can be reshimmed on the 4.2 SC L322 2007.

This will solve the valve clearance issue and the fact the chains need replacing due to being extremely slack and clipping inside the engine.

Will be changing all Lambda sensors as part of the process.

Chains, tensioners, guides replacement, re-shimming and Lambda sensors all replaced to take 24 hours of labour. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

really odd that you are not getting any P0011 or P0021 error codes if the timing chain is slightly off

https://www.carobdcodes.com/jaguar-p0011-i...nk-1.shtml

Yep never seen that type of code ever. Only ever lean codes. I take it you saw picture attached where the chain is hitting internal part of engine. But still no codes like the one you highlighted. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

you don't have to watch it all, but start at 12:50 into this youtube video, it talks about the M62 engine and the timing chain guides, early signs of this happening are when an error code is reported on Camshaft Bank A ( bank 2 ) Over Advanced error code ( P0021 )

the M62 engine goes so catastrophically wrong if the plastic timing chain guides start to perish - all because the "Timing Chain Tensioner" has not been used to provide some more tension on the chain, which can prevent the plastic timing guides being thrashed to bits

also see video at 15:55 into the video for better explanation - some good stuff indeed - well I thought so


&t=1040s&ab_channel=Timm%27sBMWRepairsandInformation

I'll check them out thanks for that 👍

However mine is the Jauguar AJ engine not the BMW. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

Bmw Tim's channel is pretty good But that clip is of no use as you have the jag engine not the m62.
Iv just had my chains, guides, etc done on my M62 is time consuming but pretty straight forward.

Just a quick question hopefully.

If a compression test got 170 psi minimum across all my cylinders on my l322 4.2 SC engine does that mean my valve seats are ok as well or does a compression test not test those?

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

Not sure what compression one of these engines should have but if yours is in the acceptable range then it would indicate that your valve seats are not warn to the extent of them leaking or them having recessed to the extent that the valve doesn't fully close. So yes I think it would indicate all is well.

Great thanks as that will save taking my heads off which saves time and money. Excellent. Thanks for the reply. Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles

So two options to resolve my issues. Spark plug reseat might have solved misifre now. However remember the chains need replacing with tensioners and guides no matter what. I'm just in two minds as option 1 I might be able to afford but I am concerned that not sorting the valve seats will still minimise the life of the engine even if I do do option 1. What a choice any feedback appreciated. What would you do in my shoes? No codes coming up but with th timing chain picture actually touching the inside of the engine its clear they are slack and need replacing. Can I get away with only doing option1 or is option 2 essential due to valve wear readings?


Request 1: Initial enquiry:

Parts required to sort valve clearances, replace timing chains less Lambda sensors which you have = £572

3 - 4 days labour: £2040 - £2720 (We will only charge you for what we use but you need to protect for the worst).

Total £2612 - £3292 + VAT

Valve clearance measurement reminder. In bold all the valves below minimum standard of .180

Bank 1 (offside)
Cyl 4
Inlet A - .178 Exhaust - .205
Inlet B - .178 Exhaust - .205
Cyl 3
Inlet A -.178 Exhaust - .205
Inlet B - .178. Exhaust - .205
Cyl 2
Inlet A - .127. Exhaust - .205
Inlet B - .127. Exhaust - .205
Cyl 1
Inlet A - .127. Exhaust - .127
Inlet B - .178. Exhaust - .178

Bank 2 (near side)
Cyl 4
Inlet A - .127 Exhaust - .229
Inlet B - .178 Exhaust - .278
Cyl 3
Inlet A - .127 Exhaust - .178
Inlet B - .127 Exhaust - .229
Cyl 2
Inlet A -.178 Exhaust - .229
Inlet B - .178 Exhaust - .229
Cyl 1
Inlet A - .127 Exhaust - .229
Inlet B - .178 Exhaust - .278

Request 2. As above plus re-seating your heads with LPG specific valve seats and rebuilding.

Parts required to sort valve clearances, replace timing chains less Lamdba sensors which you have = £572

32 Valve seats replaced £1435

32 Valve seats cut to valves £533

Time to do this part is unknown as it is a third party so we are at their mercy.

4 – 5 Days labour (including rebuilding heads, note on hours as above) £2720 - £3400

Total £5260 - £5940 + VAT



If you want to save time and have our heads re-seated rather than the car waiting for yours to be done, add £1400 + VAT for a pair of heads Range Rover Vogue SE 2007 L322 4.2 Supercharged 121k. Engine rebuilt @ 120666 Miles