Bongo Fury

Hi
I have a flashing hold light mystery…. Started a few weeks ago but was very elusive- no issues with gears or power- just the hold light flashing on usually about an hour or more into a journey. Then of course it would stop as soon as i got chance to get to the diagnostic port. Finally it stayed on once we finished a drive and we got to code 36 (not on many lists): glow plug relay. Got the relay off and was full of water. Cleaned up- all good until again the light appeared… changed the glow plug relay (brand new)…. And happily set off into the sunset… until the evil flash started again.
Finally it’s stayed on so i could get the codes. 16 and 64 which i think are EGR position sensor and 3-2 timing solenoid valve. Still running perfectly. No issues with gear change (automatic), no noises, knocking, smells or power loss…
I asked the question on Facebook if these are things I can clean/replace on my own it is it off to the mechanic? Suggestions came back that it could be the crankshaft sensor but i think that may be from them having a flashing hold light rather than the specific flashing codes…
Any help greatfully received!

I had similar few years ago.....de-gunked the EGR system, cleared the faults / hold light, but the job was a real faff. I considered removing / blanking the whole EGR system at the time as doubt it has any benefit to man, beast or MoT test at all.

The hold light came back about a year later, from memory code 16, but this time suffered intermittent reduced power. Could not solve that myself, but after extended diagnostics, which involved giving up with the codes and just exchanging each of the four sensors connected to EGR for known working units until found the faulty item, it was cured and back to running perfect. ADS automotive in Bristol were great for the diagnostics and pragmatic problem solving.