2015 Vauxhall Corsa 1.4, intermittent dash light faults HELP

[Eddy16v]

Hi everyone,

I'm hoping someone can point me in the right direction with this one, my mrs has a 2015 Corsa 1.4. Within the past month or so its developed an intermittent issue with throwing up dash lights but with no running issues, its a bit of a random one so i'll try to detail as best as I can...

Go back to about a month ago, the car was fine, serviced regularly, well maintained 70k miles, driven like miss daisy etc etc come out one sunday morning go to start it, car turns over for a good 10 seconds before starting and lights up the dash like a christmas tree. I plugged my cheap ebay code reader in and get the following codes;
P0641 (x3) - Sensor reference voltage A circuit open
P0365 - Camshaft position sensor B circuit bank 1
P0340 - Camshaft position sensor A circuit bank 1

Also, the service 89 message was displayed on the dash.

I tried new camshaft sensors but it did nothing, left it until we could get a garage to look at it. Took it to the garage a week later, the guy was scratching his head, cleared the codes and that was that for 150+ miles of fault free driving.

Then it happens again, this time more dash lights were on and the car went into limp mode, same fault codes came up on the scanner but the dash warning message displayed Service 84 (reduced engine power). Took it to another garage, they couldnt figure it out, cleared the codes and AGAIN 200+ miles of fault free driving.

Skip forward 2 more occurances of this and 2 more trips to the garage, with absolutely no clue as to whats causing the issue.

The mechanics and auto electricians mentioned there were codes for low voltage and reduced air flow, again car drives fine apart from the limp mode incident mentioned above.

Come out to it this morning, again took about 10 seconds of turning over before starting, and throws up the same codes as above plus an additional P00C7 code - intake air pressure??

Anyway my mrs has lost faith in the car and wants to flog it cheap but i dont want her to lose money on it before ive exhausted every opportunity.

Can ANYONE shed some light on this, as above, theres been a good 200 miles of fault free driving between these instances and even with the camshaft fault codes the cars driving fine.

Thanks in advance!

[GreenV8S]

Sounds a bit like a dodgy connection. Check all the fuses are held in tight and see if you can introduce a fault code by wriggling the loom to the cam sensor, or any loom connections you can see.