Is there a special tool for working with this style clamp? It's always a hassle using needle nose or regular pliers. TD

I use a fairly large right angle nose pliers, it grabs them just fine. flat-nose pliers work well, too.



or these,

Air flow meters have similar Bosch #s and Volvo #s but a different small 7 digit # just below the BOSCH name. Internal vanes are slightly different. I'm using '91 brain so should I use '91 air flow meter or is it trail & error?
https://cimg0.ibsrv.net/gimg/volvofo...b6aaa7a214.jpg

those are both LH2.4, they should both use the same ... guessing that extra number is a production lot number or something. All Bosch AMM/MAF's are 0280212xxx, for LH 2.4, the xxx is 016 ...

Why are there differences in the wires & vanes you see when you look down through the bore of the two AMM/MAF's?

I'm also wondering if I should use the in-line heater valve from the '91SE car since I think it's a more sophisticated climate control system? It does look a little different but vacuum is vacuum so I'd rather not go through the hassle if not necessary. TD

they are probably interchangable, but thats just a guess. its possible the valve on the 940SE's climate control system is proportional rather than just on/off.

Thanks. I'll just try using the one that was on the '93 engine when I installed it since the hoses were fairly new. I'm getting weary & just want to drive this car ASAP! TD

fwiw, I'm only finding heater valve 1259327 listed for 1991, but the ATC (Automatic Climate Control) shows a 'thermo contact' on a T in the heater return line.

also note, there's a bunch of different aftermarket vacuum actuated heater valves people use to repair these. this is, i believe, the current VDO replacement part...
https://www.autopartsapi.com/eEuropa...76bb76300b.jpg

the originals were probably more like this,...
https://volvoforums.com/forum/attach...lve%5B1%5D.jpg

this one works too, its from some entirely different brand car,
http://www.joetlc.com/images/9447896a.jpg

The original sure looks very robust! The VDO replacement is the one from the '91 SE car and the third one is what is from my '93. As you mentioned, looks like the difference is between being proportional vs being simply on/off. Guess it would be worth the effort to install the VDO model now while the system is empty, translation... no mess!!

those are all on/off.

do check the heater hoses from the original 940SE to see if there's a thermo sensor in a T on the other heater hose... if so, then you definitely want to keep that (or if you are replacing the heater hoses, splice that T into said other hose...)

The Phoenix rises! From this,

https://cimg9.ibsrv.net/gimg/volvofo...47cf871b61.jpg

....to this! Thanks for all the help Pierce! TD

https://cimg4.ibsrv.net/gimg/volvofo...e144cf542b.jpg

:thumbsup: