The wife asked me to check her car over before she goes back to work on Monday and there's something odd going on with the tyre valves.
Using a Topeak digital gauge I get a pressure reading but if I try and inflate the tyres there's no increase in pressure. I've tried a 12v digital pump but it just ramps up to 100psi in a matter of seconds and trips out and I tried my proper compressor and at 6bar outlet pressure there's no increase in tyre pressure. If I press the centre of the valve with my fingernail it'll let air out.
What's going on?
Try replacing the valve cores. I have the same problem with some of my bikes, the fitting on the pump doesn't quite contact the valve core enough to open the valve.
I'm loathe to remove the valve core in case I can't pump the tyre back up.
The 12v pump works fine on the valves on my BMW and has nothing in the fitting to compress the valve.
Scratch that, it no longer works on the BMW's valves either. I'm guessing that something has fallen out of the fitting?
There must be a "plunger" (I'm sure technical terms are available) in the middle of the pump connector, as the valve core has to be depressed in order to get air past it.
Sorry if this is over-simplistic, but have you tried pushing the connector on really hard, whilst it's pumping, to see if it is enough to open the valve core up?
Edit: just seen your "scratch that" post. Yes, you may be right. You can buy a new connector, rather than a whole new pump - I got one and fitted it to my little electric pump, so I now have a posh brass "quick release" connector, instead of the fiddly screw-on thing that it came with...
Edit again: this one: https://www.amazon.co.uk/dp/B00FZJO070/ref=cm_sw_r_cp_apap_41UjvotRKE7q9
Thanks. That's the same type of fitting that's on my proper compressor but it's worth a try.
Try your bike track pump. They are OK for car tyres, but take a bit of effort.
Good news - glad it helped!