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4x4 Cos Revs counter jumping

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Old 27-08-2009, 10:12 AM
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ghutcho
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Default 4x4 Cos Revs counter jumping

when driving along the rev counter jumps and bounces around but revs on the engine stable? any ideas? cheeRS
Old 27-08-2009, 03:18 PM
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tabetha
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Could be the long downhill for the tacho, but first I would try a wire direct from the NEG of the battery to the earth point on the plenum cover.
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Old 27-08-2009, 03:23 PM
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My 4x4 does this all the time, there are 3 multiplugs at the back of the engine fixed to the bulkhead, it may be what Tab has said, or bad connection in one of them, i'm sure it's the middle one, but check all 3, these ALWAYS fuck up and alot of people solder the wires toghether and bin the connectors all together.
It can also cause a missfire as the ecu doesn't read the correct RPM.
Old 27-08-2009, 03:37 PM
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Jimboxr4x4
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As above - I had exactly your problem and after changing loads of things I found it to be one of the multiplugs. I removed the plugs and soldered the wires together and it fixed the problem for me. That was two years ago and not happened since.
Old 27-08-2009, 05:36 PM
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tabetha
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I forgot the GAY WD has those!!
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Last edited by tabetha; 29-08-2009 at 03:16 PM.
Old 29-08-2009, 09:26 AM
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Stu @ M Developments
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Its the bulkhead connectors.
Old 29-08-2009, 10:25 AM
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Originally Posted by Stu @ M Developments
Its the bulkhead connectors.
indeed it is
Old 29-08-2009, 11:35 AM
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Originally Posted by ghutcho
when driving along the rev counter jumps and bounces around but revs on the engine stable? any ideas? cheeRS
This is your problem area

Old 30-08-2009, 04:33 PM
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yep i had the same problem, with missfire too. soldered them together and all was fine, after changing all engine sensors of corse lol
Old 31-08-2009, 08:12 AM
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rog
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Originally Posted by forevaford
yep i had the same problem, with missfire too. soldered them together and all was fine, after changing all engine sensors of corse lol
As you said mate, can also cause a misfire too, didn't realise it was a big problem that my rev counter was fubar, and that the misfire i had was related to this, until i got my secs monitor, the display showed the ecu was seeing double rpm of the rev counter so it was misfiring like a b*stard. Ok now though.
Old 31-08-2009, 12:42 PM
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ghutcho
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Cheer peps I got rid of the connectors altogether, and soldered the wires. tested and it's working fine now, thanks for all your help
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