I just replaced the 10 amp fuse on the OVP relay today. It seems to have settled the rough idle problem I have posted a few weeks ago. Should I replace the whole relay? I used dielectric grease on all the contact points to seal out dust and water. I ordered a new OVP and a new fuel pump relay. I am going to replace these as prev.maintenance on the car. What causes the OVP fuse to blow? Will it also blow the relay itself? Thanks, Joe

Hi,

I would also like to know if my OVP relay is working properly..I have a 1988 300E W124. The fuse on the OVP relay is not blown...but this OVP seems like a very common problem. Is there a way to test the OVP relay to make sure it's working properly?

Thanks.

Thanks benzmac, I replaced the OVP and now the car idles so smoothly. I guess that it must have blown. What can you do to test the OVP? Thanks, Joe