Time for an update...
Last weekend I tried to measure the output from the vacuum pump and managed to convince myself it was faulty, so I located a used spare and fitted it today.
Having done that I measured the vac again and was only getting 10in/hg at any rpm.
After a bit of dismantling and measuring with a vacuum test pump I discovered that my governor was actually faulty, so this replacement exercise is actually required after all.
As per previous posts the connection on my new governor is not the same as the Volvo unit so I started there.
I was going to cut and splice the VW connector I got from the scrappy into the loom, but I had a change of heart and decided to make a patch lead just in case I wanted to revert to the original part.
Using the VW connector shown in a previous post, I attached a
connector I bought from ebay. I'm sure these could be bought cheaper if you have a Farnell account (or similar), but I was pushed for time.
Comparison of original governor connection and new plug:
Patch lead made from VW plug and new plug:
Turning to the governor itself, once off it looked pretty identical to the VW/Audi part I had bought new. The main difference seemed to be the filter over the vent pipe.
Fortunately the vent filter assembly just clips off and can be fitted to the new part, so here is the new governor ready to fit;
Actually, it wasn't ready to fit - the new part has slightly narrower mounting slots although this was easily sorted with a round file.
The new governor with patch lead & filter all fitted:
After a brief test drive I can say that I think the car is stronger in the low/mid range - because the VNT will now be working It's smoother at idle - because the vac engine mounts are working, and I think it's less smoky as well. I am also hoping that the fuel consumption will improve, but only time will tell.
I did notice that when stationary (bonnet up) if I rev the car I can hear a venting type noise (dump valve-esque) when the throttle is released. This was not there before (probably due to no vacuum) and is not audible when driving the car.
I'm also happy to say that the persistent ECM6805 that the car has had has now gone
