Alternator / RPM gauge problem

[blazza13]

Not to sure if these problems are related. However my 96 Disco V8i has a intermitted problem with the RPM bouncing up and down, when this happens its not actually effecting the motors RPM?

Whilst i have this problem, I have another with the alternator maybe? Noticed that all my electrics dim up and down, though this does not happen all the time, but it when it does happen and you shut the engine off it stops. Checked the regulator on the Alternator but its output is fine 14volts... could it be the alternator failing slowly internally?

Cheers
Blair

[Mark86]

Yes it could be my fuel injected classic rangie did same thing tacho had a mind of its own for about a month i then my alt light finally came on done the alternator all fixed. ( right at the end of its life she is started running rough as well).

Mark:)

[Reads90]

Not to sure if these problems are related. However my 96 Disco V8i has a intermitted problem with the RPM bouncing up and down, when this happens its not actually effecting the motors RPM?

Whilst i have this problem, I have another with the alternator maybe? Noticed that all my electrics dim up and down, though this does not happen all the time, but it when it does happen and you shut the engine off it stops. Checked the regulator on the Alternator but its output is fine 14volts... could it be the alternator failing slowly internally?

Cheers
Blair

Check your earth straps. The one to the engine (clean it up and make sure its conecting well) and maybe put another one on the gearbox

[4bee]

As the rev. counter rpm is dependent on the alternator, it might pay to inspect the connections at the rear of the alternator for loose, burnt or dirty connections before diving in too far.

[Stepho_62]

Recently I was moding the dash in my 300 TDi and noticed that my Tacho wasn't working. I swore, pulled it out, sent it to Launceston to the VDO agent who tested it and rang me to say there was nothing wrong with it.

When I got it back I put it back in the dash and it still souldn't work:mad:. When checking the dash lights I voltage checked the battery and discovered it was 12.2 volts.

Then there was an audible click in my head. I put the alternator light back in and it started generating a current. Funny thing that, my Tacho worked again too.

Moral of the story is if you alternator is intermittently generating current it will be reflected in your tacho IF it is run off the alternator.

[PeterM]

The tacho reads off the alternator so I would definitly get your alternator checked out/replaced and all problems will be solved.

[DiscoMick]

Yes my tacho was sometimes bouncing around a bit before the alternator finally died. Also had a battery warning light coming on some times, but no pattern to it. Get the alternator checked. Should be doing about 14.

[justinc]

Tacho wire is to the 'W' terminal on the alternator. Do not trust the factory 'clip on' terminal plug, remove it and fit a new female crimp terminal and all should be OK. The clip on female connectors will loosen up after being pushed on, and the weight of the loom can hang off them making it worse.

JC