Guys, which way around do the plugs go on a 540i... I distinctly remember a shogun post a while ago saying that on a 7 series V8 the left sensor plugs to the right socket and visa-versa - is this true for an E34?

Was under the car the other day and noticed the left sensor in the left socket and right sensor in the right socket - the car ticks over well, but I'm only getting 17mpg out of a manual 540... when I should be able to easily push it over the 20 mark!

I used to get 22 ish - I think one of them may have gone duff! Will get under the car at some point and check them out.