Date registered: May 2010
Vehicle: 1989 Mercedes Benz 300SE, 246k miles; 1976 MB 450SL between 95k and 250k miles
Location: Santa Barbara, CA, USA
Mentioned: 0 Post(s)
Quoted: 15 Post(s)
OVP Relay: what does it do, exactly?
Sorry for visiting a topic that seems to have already gotten a lot of airtime, but even after digging through many forum threads, I cannot find a definitive description on what the OVP relay does and why Benz owners are always suspecting them as THE culprit for many engine woes, and subsequently replacing them only to find that the problem still exists??? So, two questions:
1) How can you tell if the OVP is "bad?"
2) Does it really cause different types of engine sysmptoms, or are they very well defined, i.e. can you tell when you really need to replace the bugger?
Why I'm asking: my '89 300SE starts up a bit roughly after sitting for awhile, kinda stumbles and coughs and then begins to purr. If it only sits for say 1/2 hour, it seems to start more smoothly. An earlier thread of mine resulted in someone suggesting that I replace the OVP relay. Others have done it and smoothed out the starting problem. I don't get it?
Also, is it recommended to buy a new one rather than a used $20 one on eBay that's guaranteed to be good?
Happy New Year and thanks for all of the great work you guys and gals do on this forum!