Temp gauge and lights and rev counter.

Had my 1.8gti cabby in garage to change the coolent now it has a prob,both temp gauges saying the car is hot even from cold digi-one says 160 and the needle goes right up with the light flashing.then i put my lights on last nite the hi-beam went back to front and the rev counter died as well and the horn stopped working.i think the garage must of hit something as everything was fine before it went in.also i think i can hear a spark like something earthing but can't see it.should i change the leads and the coil as i thk it has to be in the engine bay and not behind the clocks,with the hi-beam being reversed???

You may have an EARTH missing check the engine especially at the rear for loose brown wires , or take it back to the garage and demand they fix it free as they seem to have caused it

earth from head was left off when they took rocker cover off.

Just bought a Mk1 gti and have the same problem as you had.  Checked the earth strap on the head and discovered that its missing!!  Had a look for the brown wire, but cant see it.  Can you tell me where the brown wire comes from so I can try and trace it.

Many thanks