Ronnie

You don't have to remove the engine, but many do for ease of access to chain.

The squib is the part on the steering column, so you may have an issue there.

Have you looked at your cluster to see what's up with yours? Sometimes it's the plastic cog wheels that break. You can get repair kits for them.

Has it been dry stored? These suffer badly with corrosion, especially inner wings.

How many miles? These go for anything around £12,000 and upwards, depending on condition etc, I've seen some for £30,000

You need to get a diagnostic done, to see what fault codes come up. This will point towards the issue at hand.

Have you had a diagnostic done on the car? When was the last time it was regassed?

Part numbers. 33322406289 33322406288

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Something could be back feeding the instrument cluster. Check the wiring at the boot hinge.

I've been away for ages. These engines are common for sooting up. The inlet and head get sooted up, restricts breathing/flow. DPF gets sooted up. Tunap is very good for unblocking DPF, perform a regen and you'll be surprised how much back pressure reduces and how quickly. Always worth checking coolant temps reach high enough when driving for a regen to perform.

Sorry, yes had a major hack of spammers, but on top of it now. Sorry for any inconvenience.

Are the sensors showing up as fault codes or are they not reading up correctly on live data? It's not uncommon for the modules and wiring to get damp/water damage on these.

How cheap is the kit? As normally it's very expensive, and the price to buy the kit just to fix your own car wouldn't be worth the money. Those kits are normally in the thousands range.

Normally it's because the O ring style gasket flattens out. You can get a new gasket for them fortunately. You'll need to remove the pump and take the top off to replace it, while you're there you should replace the O ring between the pump and cylinder head.