Rev Counter Problem

[Tonybolony]

Hi,
I recently started a thread re my rev counter giving erratic readings. Having watched it for a few weeks now, it seems to give linear readings (when comparing mph to rpm in gear) up to about 3k rpm, above which the needle rises erratically between 3 and 4k. Any suggestions?
I dont know if this is related to a poss ecu (Homefries fitted) fault, but starting from cold is easy, and she immediately settles to a smooth idle (900-1000rpm ish), but once warm/hot the idle is unstable, almost to the point of cutting out. Pulling on the wheel, or the Rad Fan cutting in spikes the idle speed up to maybe 1200rpm (normal??).
It's not a regular miss, ie plug/coil fault, and I have cleaned MAF and Lambda connectors with ECU fuses out.
And whilst I have your attention- any suggestions why the ABS light will occasionally not go out on engine start, but Ign off-and-on again, and the light goes out. Battery voltage problem?- even tho she cranks well on the Starter???
Cheers Lads.

[andyg plym]

daft question tony but have you checked to make sure your white gauge isnt peeling behind the needle?

[Tonybolony]

Not daft at all, Andy. Very relevant, but unfortunately not the answer

[andyg plym]

have you checked the isv (idle stabalisation valve),and regards to rev counter could be an issue with the rev counter itself,i doubt its the ecu-if you take the clocks out its a green and blue wire you are looking for on the back of it.maybe make sure its not loose or corroded terminal in the plastic housings

[Tonybolony]

I'll check wiring to the back of the dash, but re the ISV, dont think it's at fault, cos the idle revs rise when under load.

[andyg plym]

clutch slipping? lol

[Tonybolony]

Naa, but one of the number plate lights is out

[andyg plym]

just turn the wireless up

[johne]

I'll check wiring to the back of the dash, but re the ISV, dont think it's at fault, cos the idle revs rise when under load.

It does sound as though the ISV is sticking. I'd give it a good clean with carb cleaner. Cleaning the ISV should be a regular service item.

John