fuel pump relay

[Braincrank]

How do I test a fuel pump relay?
I as driving today and the car cut out mid drive. Stone dead without any warning and all the dashboard lights came on ...
I switched off the ignition and started again and the engine was running as smooth as if nothing had happened ....
The ignition leads and plugs are new .
I am now thinking it might be the fuel pump relay which is still the original and 27 years old now .
Is it worth trying to get a second hand one or rather get a new one ?

 

[neilrr]

What's the part number on yours?

 

[Braincrank]

 

[Braincrank]

Can I get a aftermarket one or is it a dealer part ?

 

[grober]

Take the can cover off the relay carefully [ you are going to replace it] and run a soldering iron over all the connections on the small circuit board inside. These connections often develop stress/vibration cracks which can cause loss of electrical continuity.
http://www.benzworld.org/forums/w126-s-se-sec-sel-sd/1654480-fuel-pump-relay-failures.html

 

[Braincrank]

Same thing happened while the missus was driving , about 2 weeks ago .
I cleaned all the contracts of the relay since I couldn't think what else it could be and drove the car without any further hassle.
I don't really fancy that happening while on the motorway since when the engine is dead I obviously don't have power steering 0-: and that's not very funny ....

 

[neilrr]

PM'ed you.

 

[stwat]

I bought a new one from car parts 4 less and resoldered the old one to keep as a spare in the car.

It's also worth checking the connections on the fuel pump. If you have an OVP relay, they are also known to go bad due to dry solder joints.

 

[Braincrank]

I got a new OVP relay a couple of years ago but I have never (in 15 years) changed the fuel pump relay.
Good idea re keeping the old one as a spare.

 

[Braincrank]

Found 4 dodgey connections and r-soldered them . Car is running fine so far.
Hopefully that's that sorted !

 

[grober]

Only time will tell of course but its usually a good fix if the rest of the relay internal components are in a healthy state.