OK, this is a weird one. Note that this has never happened before, had the aftercooler wired up the same way for almost a year now.

So I walk into my garage tonight and hear something whirring, and realize its my aftercooler water pump on my Comptech SC kit. Its running full bore, and the keys are not in the car. Car has been off for three hours.

So I put the key in and start the car, then turn it off and remove the key. The pump turns off with the car, and everything is silent. Well I start doing other stuff in the garage and slowly I start to hear the pump start whirring again. Really slow at first and slowly getting faster, till it eventually gets back up to full speed again.

What the hell?!?! The pump relay is wired in just the way Comptech tells you to... power from the air pump relay, signal from the under-dash fuse box ignition terminal, power out to pump, and ground to a chassis ground. This is the first time I have noticed it do this; I would have heard it this morning if it had been doing it over night or anything.

I have the battery unplugged for now to keep it from running the pump all night. What is happening to my car?!?!

 

Hmm, check the wiring and relays I guess?

 

Yeah maybe the relay failed in closed position? Cheap to replace. Radio Shack $5

 

Don't listen to the guys above.. The obvious answer is that your car is possessed..

 

Possible. Mine is for sure

 

Easier way is to just pull the relay for now when ur it using the car, I second a possible relay go bye bye

 

Relay for sure .

 

Thanks guys, seems to be acting OK right now; I'll replace the relay this weekend.

 

FYI - Relay was blown. I ended up swapping over to the Bosch pump while in there, and put the new relay inside a RadioShack project box to help protect it better (top-left in picture). I think the old relay got some water on it and caused it to fail.