Wee update to keep things rolling on my WIP. I've been posting various things all over the site but haven't updated anything here, so here we go:
EML light is now out. This came on when I'd filled up with costco fuel, I think this was a big coincidence, however it had me thinking could it really have been that. I came to my senses and thought no it can't be.
So at the same time, or just after this event, I was planning to replace the back end of the exhaust, well the back 2/3s as it was toast, mainly around the join to the tail pipe. I had hoped that maybe this was causing a problem with gas flow and that the code for 02 sensor was on as a result. Idk but a fair assumption at best.
I hadn't done anything else to the motor so I was fishing for other things that could have fired the code off.
Right about that time I also experienced a judder and at one point , a stall, when I was pulling up outside house. This happened a few more times so I was getting edgy now and had lost confidence in the reliability of the car.
This then led me to think that the crank sensor was on the way out as I had read on here so many times, so bought one of those, Gen GM one. I then decided to give the vac pipes and connectors another good look over, and the only thing I could perhaps suspect was the plug going onto the airflow meter bit at the front, which the plug bit that secures it on was broke. However this happened ages ago when I done the timing belt I decided probably not that, as it still felt secure in it place, and had no issues since last year. I got a tie wrap and secured it round the plug then tightened it so it would pull it right into the plug socket.
Immediately after this, the EML light was still on, so I decide maybe it was the exhaust sensor and/or crank sensor etc. I then drove down to my folks to drop off a few things, stopped for fuel on the way and when I restarted it voila the EML light was out!
I had heard that it can take a bit of time for codes to clear, so it must have been this loose connector. Just goes to show the carnage a loose connection can cause. Codes were saying one things but it was that. It also goes to show how that a code doesn't always mean that, and ironically, the code will only be correct if the whole electronic circuit is not breached in any way.
I checked tyres a few days ago as well and they were all around mid to low 20s, so bumped them up to 30, and fuel economy is also much better, and the car is running very sweet.