I have a 1982 380 SEL. It is a gray-market (German) car converted to US emissions with some rather cheesy-looking mods.
It has been parked a lot. A while back, it became difficult to start if parked for too long, requiring priming the intake with gasoline. After that, the pump would continue to run. Recently, it would not go at all. I found that the pump would get warm, but would not turn. So I replaced the pump, but now the pump does not run at all. If I hot-wire at the pump, it runs. Can anyone advise me where to find any relays or fuses (or ???) that might be involved?
Also, it has developed idle-speed issues (unrelated) when warm. When I unplug the wires to the idle-air device, the motor speeds up. When I plug in in, the motor goes very slow. Any suggestions?
Also, I think the motor may have been changed... are there numbers to ID the motor?

Thanks
Ken
Riverside CA

 

There are several tags on the car's body to ID the engine and body. One should be on the reinforcement that the hood locks into, the firewall is another place to look. I have a fast idle problem with my 79 SLC. I adjusted the idle speed down a bit, which did lower the idle when the car is in gear and you have the brake on, which a engine should do underload. But in park I can't get it below 1100RPM's and in gear 850 RPMs. It should idle in park of neutral around 700 to 750 RPM. I spoke to a mechanic who knows these cars well and he thinks it could be the idle control valve, (expensive) or perhaps a vacuum leak. The previous over had changed the right side valve cover gasket but not the left, which he left in the trunk when I bought the car. A slight crack in the gasket could also cause a high idle. Also, there is a CO2 adjustment that could cause a high idle. I have slowly changed vacuum hoses, that are accessible even if they look OK, as 26 years is a long time for a piece of rubber with plastic around it. As far as the fuel pump, if the new one doesn't work, I am wondering if there is a electrical problem as you say in the relays, as you said. On my car the fuel pump relay is located in the fuse box and ID is 21, hope this helps.