Rev Counter

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MULLEY
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Rev Counter

Post by MULLEY »

For some strange reason today for approx 10 mins the rev counter started to flicker up & down by as much as a 1500 revs, even in neutral it was dancing away. The revs never seemed to drop below what the cars actual revs were in any given gear, however, even in neutral it was jigging up & down.

At 1st i thought it might be the alternator packing in, but there was no warning light & from memory the rev counter just gently died over a period of time as the battery would start to go flat, so fairly confident it can't be that.

Any ideas of what may have caused this & why it went away?
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kiwi
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Post by kiwi »

My thoughts would be a faulty rev counter.

My TRS when you first start the car for several seconds often up to a minute the rev counter will not read. Unfortuanately dont have a spare to check with other than out the other TZS. Lot hassle for minor problem though for me anyways.
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rayfenwick
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Post by rayfenwick »

Almost certainly not the case here, but my former A1 v6 12v XM rev counter used to do silly things like that. It turned out to be the battery that was low voltage causing the problems. Hopefully this will be some use to someone at some time... :?
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Tim Leech
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Post by Tim Leech »

Arent BX diesels known to have rev counter problem? Didnt jackson have his mended by bullwinkles and it was the flywheel sensor/sender or summat?
Last edited by Tim Leech on Thu Jul 14, 2011 9:17 pm, edited 1 time in total.
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mat_fenwick
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Post by mat_fenwick »

My money would be on the sender which drives the rev counter. It lives down the back of the engine picking up from the flywheel. I've come across a number of XUDs where there have been similar symptoms - tending to worsen when it was warm. Fixed with a new sender which was IIRC about £17 from Citroen. Worth checking the connections to it - a grey wire to a brown 3 way multiplug near the HP pump.

EDIT - crossed post.
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ken newbold
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Post by ken newbold »

mat_fenwick wrote:My money would be on the sender which drives the rev counter. It lives down the back of the engine picking up from the flywheel. I've come across a number of XUDs where there have been similar symptoms - tending to worsen when it was warm. Fixed with a new sender which was IIRC about £17 from Citroën. Worth checking the connections to it - a grey wire to a brown 3 way multiplug near the HP pump.

EDIT - crossed post.
My money too :)
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Post by Brian »

If the sender is found to be faulty..
You can use the TDC sender (If you have one), this will work, although the resistance is different.

Good luck
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