Hello from denmark

I have recently bought me a 1997 Skoda Felicia LX 54 BHP.

There was no rev counter in the car when i purchased it ...

But now i have put in a glx instrument cluster... And everything worked perfectly until yesterday ...

The problem is following:

In Idle = no reading on the revs / 0

2500 - 5800 RPM approx = Revcounter is showing between 0 - 4500 RPM not any higher ..!!!

I have tryed 3!! other instrument clusters even 1 from a 1.6 aee engine and result are exactly the same...

I have heard that this should be a commen failure, but what is the solution ???

Hope anyone in here can help, i am starting to spin just like the revcounter

Best regards

Kenneth

On petrol models the tacho signal comes straight from the ECU, so chances are it's the ECU itself at fault, unless you've also started having engine troubles, in which case a faulty crank sensor is possible, I suppose.

One easy thing you do is get a meter/test lamp on pin 7 (yellow wire) of the right-hand (yellow) cluster connector and see if the ECU's actually outputting any kind of signal at all at idle.

I think it is a problem in the ECU.

I had recently replaced the crank sensor and tried a new rev counter and instrument cluster but still nothing. Tried bypassing the wire from the ECU straight to the cluster but still no luck so just put it down to there being something wrong in the ECU.

Phil

yeah, i would guess it's the tacho driver circuit in the ecu which is to blame, i remember ages ago when phil^^ has his L&K he never solved it iirc?