Can anyone tell me the correct way to test the ACD/AYC pump on an Evo X? It's not building up pressure, and I just want to make sure the pump itself is working before I drop $450 on a rebuild kit. I know what to listen for on the pump, but I just am not 100% sure how to activate it so I can listen to it.

I know with the 8's and 9's you can put the key in the on position w/o starting the car, and push the gas pedal down all the way and listen for the pump. I just don't know for sure if that method works for the Evo X.

 

If you had a the acd reflash done then I would doubt that it's a motor issue. The reflash made it so that the pump would shut off as soon as the computer realized that pressure wasn't building so that the motor wouldn't burn out. Chances are you just have a lot of corrosion and need to have it rebuilt.

 

To answer the original question: there's no known pedal/key trick for Evo Xs. To test the pump's motor you must use a MUT-III, EvoScan, Kiki's tool, or just attach the power wires directly to the battery. My suggestion, since you're going to have to pull the pump out anyway, is to test the motor with the pump on the bench, then take it apart as much as you can to see how bad the motor looks.

 

Okay thanks again Iowa. I've tried PM'ing Kiki, but haven't gotten a response back from him yet.

 

how do you do this with just the battery?

 

If you're asking how to test the motor with only a battery, then you just feed it power. Red is positive; black is negative. If you want to do more than this, such as make your own bleeder tool (like Kiki makes and ACDTuning used to sell), then that's a bit more complicated and I don't feel that I'm competent to answer. Hopefully, someone else will.