Over heating when not moving

Hi can anyone help me please? My 86 cabrio gti is overheating when in slow moving traffic ie needle far over to the right and red light flashing and the fan cuts in at the last minute. But when I get over 30/40 everything seems fine ie needle in the middle.

I have fitted a new fan switch and new temp sender. The oil temp is 78 when normal and between 88 to 99 when very hot, I have checked and have a good return flow of water  from the rad to expansion tank. Could this be my stat sticking and if so where on the head is it????

Cheers Chris

I don't think 88-99 is overly hot from memory? Mine used to get a lot hotter! Have you changed coolant recently? That can make a difference plus oil and filter change - if oil too old then will get hotter.

Failing that then guess worth checking the t-stat

Cheers
Andy

pic of needle over to the right please.

flashing light could be something else, ie level sensor broken or simply, too little coolant.

I assume you're taking the figures from the oil temp gauge, since this has numbers on it and the coolant temp gauge doesn't. your figures sound about right TBH.

coolant level is spot on. the temp  is of the digi oil reading, and I am changing the oil and filter tomorrow also the stat, any idea where the stat is on the head as I have what looks like 2 stat housings 1 at the front in the middle and 1 at the side???

Cheers for the advice

Why are you changing the thermostat? Its located on the bottom of the water pump. I'd be tempted to properly diagnose the faulty component, before choosing something and changing it.