1982 Euro spec 500SEC OVP relay location
 

Hi all, do you guys know if my 82 500SEC has a OVP relay? I looked between firewall and in fuse box and don’t see any relay that looks like that one. Any help is much appreciated 🙃

Odds are that there is no OVP. Look alongside the Fuel Distributor for a Frequency Valve. The valve will have fuel lines connected to each end, and a two wire plug at a 45 deg. angle. If there is no OEM installed valve, and its associated computer, there would not be a need for an OVP relay. Aftermarket frequency valve installations did not include an OVP.

Thank you for your detailed response. Now the frequency valve, is that also called a cold start injector? Or is that something entirely different?

The FV is not the cold start injector. It is a component of an emissions control system (when installed). The emissions control system consists of an exhaust gas oxygen (EGO) sensor, a computer, and the FV. Many cars of the era delivered in Europe were not equipped with the EGO controls. Generally speaking, the US EPA required a retrofit when a car was imported, but some did slip thru.

Glossing over a few details... the frequency valve looks like an injector but it's got pipes on both ends. It more or less allows a little fuel to be siphoned off the pressure side of things and that lowers the amount of fuel going to the injectors. The EHA is what later cars have to get the same effect. -CTH