1st post here but have been lurking for years....GREAT FORUM!!!..SOOOOO, read through pages and pages of charging system issues and cannot see one related to ambient/engine temp. Winter is fine(cool air)...summer and long trips I lose charge/AC after 20-30 minutes. I hate to throw parts at it and i did inspect and set gap on my CPS. has anyone else had a issue like this and figured out if its the voltage reg/PCM or a relay instead of the CPS? Do CPS's just lose their magnetic field due to heat? thanks in advance for any help

oh she's a 1992 intercooled W250 xcab 4x4 5spd....

 

I'd start by checking fusable links and relays. ASD relay might be the first to check. If I recall correctly you can swap it with one of the other two to see what happens.

JP.

P.S.: I like the colour of your truck. Body work looks real nice.

JP.

 

Because it's heat related I suspect the sensor is bad. I can't think of a way the wiring could have a problem that was only related to heat.

 

wow, that is a beautiful truck!!