Hey All, I hope this finds you well.

I've had a long-standing problem with the climate control system in my 1978 USA-spec 280ce. A previous owner upgraded the compressor and it's charged with 134a, and has the 1st gen servo upgrade kit from Unwired Tools. Everything actually works, including the A/C, however inadequate when it's super hot out.

The problem is this: the blower fan turns off (regardless of which mode, EXCEPT for defrost) when the engine is under load. Accelerating from stop (hot or cold engine), or climbing a grade (minor or not) causes the fan to just stop, until the load is removed/greatly reduced. The A/C compressor cycles even in this state. All of the flaps within the system function as-normal. It's just the blower motor!

The vacuum source for the Unwired servo module is off the intake manifold, so this to me seems like a vacuum issue, ultimately.

Does anyone have any sage advice on where I can next analyze? The vacuum lines for the servo are fine, and I have even isolated them to rule out a leak in the door lock circuit and front seat lockout mechanisms.

Thanks in advance, I welcome any thoughts!

Greg

__________________
----------------------------------------------------------------------------
Filmmaker, Dad, Citizen of the World in Asheville, NC
=== current vintage stable ===
'73 VW Thing, '09 BMW 328i Convertible, '07 Honda Ridgeline, '94 Chevy Step Van