Odd Rev Counter Problem

[darrent]

Took the Cerb out yesterday and I noticed when I floored it (i.e. a ton in 3rd) the rev counter stopped at around 4k and then dropped to zero - it kept doing this no matter what gear I was in or how fast I was going. It's the first time it's happened as I usually get the old buzzer when it's maxed out.

Any ideas?

[mike_e]

Could be the rev counter on it's way out, not an uncommon problem.

Might be worth checking the charge fuse. Sounds daft but the rev counter can play up at high revs when the fuse has cracked / come loose.

Mike

[arcbeer]

I'd check the main fuse in the engine bay. You could also check if your battery is running flat as if this fuse goes the battery does not get charged.

[darrent]

Actually my battery is fu(ked. I need a new one as it's flat as a pancake. Where abouts is the fuse that your talking about?

[arcbeer]

Not sure (other people have posted locations on here before). It's in the depths of the engine bay, better off getting a dealer to replace it.

[olly]

The fuse is right at the back of the engine - sort of under the throttle linkage. On a 4.2 it's fairly easy to replace, but on the 4.5 you have to squeeze through the purple pipes to get to it.....

It's only a cheap fuse (less than £2 - can't remmeber exact price), and a lot of people recommend changing it yearly anyway as a precaution.....

God luck !

[k-9]

I have a 4.5 and you have to remove the cover that sits over the wipers at the back of the engine bay (2 7mm allen bolts)
Then between the bulkhead and the engine there's a nice tight space, the fuse is a flat piece of metal under a rectangular plastic case, with a bolt/screw at each end.
I had the same problem and it was that at some point the wrong length screw had been used so under high vibration situations (ie over 4K) it would vibrate free.
Replaced screw all cool

[600]

I had the same problem for about 24 hours before my cerb broke down on th A1.....Turns out the alternator had died...the rev counter was the first thing to go

[shpub]

If you change the fuse, good idea to disconnect the battery first so that you don't short it out accidentally. You can reach it with an extended tool but it gets awfully close to metal engine bits which are earthed. Slip and the tool will arc weld to the engine.