Car starts fine and when warm runs fine. But when cold and in gear it wants to die with the slightest accelerator pedal pressure. Car was OK till a mild overheat due to a faulty temp thermostat, subsequently replaced. I got a vacuum diagram and checked all the vacuum hoses and connections. Everything seems in order. Replacing "components" seems like the next step but which one?
Thank you in advance for any assistance.
500 SEL w/ 5L V-8, 126 chasis

 

Replace plugs then wires. If that doesnt fix it please ask again ok.

 

Sounds more like an evap problem, or throttle body problem. Need more information as to what his vehicle is doing, like; "What does it do when it's at idle and he presses the accelerator? Is there any backfiring? Or, does it just stall? When pressing the accelerator, does it seem like there's just air, or like there is no fuel pressure?" I'm very curious to know more, if he doesn't mind. It could very well be plugs and wires, but could also be a sensor of a sort. So, I'm not in disagreement with you, it just seems like something's not being said to complete the picture.

 

I was basing his explaination on the same syptoms my 560 had then i did that and it has ran fine ever since. But yes i agree it could aslo be a sensor but it never hurts to change the plugs and a first idea (cheap and easy). Also the same thing was happening on my 300sdl and it ended up being the voltage regulator Its next to the fire wall and has a red top with a 10 amp fuse cost me $80 and fixed the problem.

 

You're right, leastest is cheapest.