How To Keep The Fuel Gauge Accurate When Replacing The Cluster -- 33

[cobbadan]

I'm replacing the cluster in my 33, i've done this once before and what i tried with the fuel gauge was to go and get a full tank, then set the new cluster to full and crossed my fingers.

It didn't work real well, it sort of worked but now it stays full for a long time, then drops like a rock.

The fuel gauge doesn't reset itself / calibrate when you switch the car off or disconnect the battery.

Whats the go ??

Is there a way to have an accurate fuel gauge after changing the cluster ?

[89CAL]

It doesnt really have anything to do with the cluster. As far as I know the fuel level in the tank is moitered by a variable resistor which sends a different voltage to the gauge depending on the level.

The gauge just displays this, if you had a problem previously it was either a dodgy gauge or something went wrong with the level sensor.

same thing as when you fill up from empty, the gauge stays at empty till you turn the car on then it slowly rises to full once the voltage is read at the cluster. I've unplugged my cluster heaps of times and it definetly doesnt have to be 'set'

[cobbadan]

So i should be able to just plug it in as it is and not change anything.

The gauge in the new cluster is currently sitting on about half, the tank is full. When i plug it in and turn it on, the new cluster gauge should go up to full.

I'm pretty sure i just plugged the last one in and hoped for the best though, and it didn't work so that's why i tried the set it to full and get a full tank trick.

It was 6 months to a year ago that i did it though, so i can't be sure if i did that or not.

What you say makes sense though with the gauge just reacting to the variable resistor.

It should work - I'll have a go and see what happens