I broke down and took my 626 into a mazda specific garage hoping they could quickly diagnose the problem since they have access to full wiring diagrams, etc. I told them I have two codes, p1632 low backup voltage to the PCM and p1500 VSS circuit intermittent.
they asked me to describe any symptoms, I told them about the rough idle under load, and the occasional hard shifting. also described various things I've checked. First thing they said was potential bad engine mounts, said I checked and changed them, they say maybe they're not OEM mounts... They were kind of dismissive of the codes like they didn't matter.
My feeling is you diagnose and fix codes first then re-evaluate the problem. I've been waiting two hours for them to actually look at the car and am feeling a bit uneasy about their approach / attitude.
So, they completely ignored the codes, saying that since they don't come back immediately after being cleared they're not important, and they tried to tell me that the engine shakes because I used aftermarket engine mounts and not OEM Mazda mounts.
We put a support under the engine which had little effect, and finally he took a crowbar and pried on the driver side engine mount showing a small improvement. Basically, they said change that mount, change the other mounts to OEM, and that it's just an old car and they're not going to find the source of the problem. And their scan tool wouldn't connect on top of it all, even though they're supposed to be a Japanese car specialty shop. Sheesh.
@Pᴀᴜʟsᴛᴇʀ2 @BobCross @DucatiKiller We seem to have a serial plagiariser... I've flagged a couple of his answers, I suspect the rest probably are too...
I think I've discussed the Touareg A/C episode in this chat room before. They were adamant that we had to replace the A/C compressor and various bits and pieces that would have cost the equivalent of a second-hand mid-sized sedan. In the end it turned out to be just a loose pressure switch. Moral of the story: don't blindly assume that dealerships/specialty garages know what's best for your vehicle and cross-reference the symptoms to their recommended fix. Sadly, this is easier said than done
