superloaf

Hi, my turbo cooling waterpump keeps running long after shut down. It used to run about 30 seconds or so but now just keeps going until I finally disconnect the relay. If I plug the relay back in it keeps running. However, the next day when the engine has cooled and I plug in the relay, it does not run. I looked at the wiring diagram and it seems that the only way that the pump will run is through the relay so I'm leaning towards that being the problem. How do these usually fail? Is it common for them to stick open when hot and then reset once they cool? I checked the relay with a meter once I got in the house and the circuit was closed so the relay seemed to be working properly at this point but this is after 15 minutes or so and it had cooled. Next drive, I'll check the relay when hot to see if it's sticking.

Also, when the pump was running and I disconnected the thermo switch, the pump kept running which would seem to further point towards the relay.

And with the relay costing $150 and up and being NLA, is there a fix or substitute for it?

Thanks

gruhsy

The temp sensor was shorted on mine. Both wires had fused together on the harness when I first bought my car before rebuilding it. I don't remember if it shut off when cold however. You could inspect them just to rule that out.

KVDR

(This probably isn't your issue, but maybe this will help someone else troubleshoot)

When I bought my car the aux water-pump would not only run long after I shut off the car, but it would also turn off briefly and then turn back on.

When I replaced the (main) water pump, I discovered that the plastic elbow that runs to the aux-pump was for an NA (plugged), so there was zero coolant running through aux pump.

Ever since I corrected that, the aux pump runs about 30 seconds after I park and it no longer does the thing where it would turn back on.

jimbo1111

Good find. Aggravating as hell I bet.

Charlie

http://forums.pelicanparts.com/porsc...mp-fixits.html