Thanks for the MAF sensor cleaning/replacement tip. No luck with this suggestion. Having spent a huge amount of time on the U.K. forums and locally, I still haven't found a solution for my Veccy based on the many recommendations that worked for the individual problems described online. Anyway, I think a suggestion from a Holden nut may have solved the problem. He told me that he had encountered the same problem in Holdens he had owned. (Limp mode problems on an intermittent basis).
The problem in his situation was the gear selector switch (I have an auto). I did some fiddling under the selector cover and found a couple of wires, unplugged two connectors and reseated them and then took it for a run.
So far so good. It's been over a week now without going into limp mode, previously it could be a couple of times a day and then nothing for days and then every day. It was so bad I stopped driving it until I learnt of the gear selector switch issue.
This may not be the answer for everyone but for my situation it looks like it might be a winner, fingers crossed!!
I just wanted to share this, as this intermittent problem has been driving me mad, spent so much time researching and trying a whole lot of different suggestions to no avail.
This just might work for you if you have been experiencing similar limp mode problems (my error code was 1895). As I understand, 1895 is a transmission error code, so with the selector possibly not sending/receiving the signal correctly the transmission gets an error message to protect it (limp mode)?????