[Alan G H]

Just two thoughts:
1. Have you recently had a clutch/flywheel changed? If so, maybe the reluctor ring got damaged.
2. Was the crankshaft sensor a genuine Vauxhall one, or a non genuine one from a factor?

 

[Alan G H]

We haven’t had the clutch/flywheel done however my partner thinks the clutch could be on the way out as it’s not sitting where is should….do you think the clutch could be causing this reluctor wheel reading issue if the clutch is on the way out?

I was thinking that if the clutch had been changed, the reluctor ring could have been damaged if the flywheel had been removed, so that appears to be ruled out.

I don’t believe the crankshaft sensor was a genuine Vauxhall part. I purchased it from eBay and it’s a Lemark brand.

Vauxhalls are known for not liking aftermarket sensors. I think the first thing I would do is fit a genuine crankshaft sensor.

 

[Alan G H]

The reluctor ring is inside the engine and wouldn't be touched by a clutch change.

It's not inside the engine, if you look at @Valer's diagram, it appears it's held on the back of the crank by the flywheel bolts.

 

[Alan G H]

I think that original diagram is a little misleading,here's a couple more

View attachment 105023 View attachment 105024

Right, I was looking at the original diagram when I thought the reluctor was held by the flywheel bolts. I've never actually even seen one of these engines, so I should stop assuming things about them.