September 2009 - Coolant Leak (Auxiliary Water Pump)

I get a call from the wife saying the coolant light is flashing and the car is starting to steam. Oh fun. I get the car over to my friends shop I.P.M. Auto Service and we start looking for the source of the leak. My first thought is that it's the after run coolant pump (Auxiliary Water Pump) which is a known problem with these car. A few mins later we find the leak and it was the after run coolant pump.

The fun part is that it's not easy to get to. If you haven't dealt with this problem before the pump is basically in the center of the engine under the intake manifold. Not as hard as changing the turbos or replacing a timing belt but still time consuming. To get to it we had to remove: intake piping, fuel rail, bipipe, air box, mass air flow sensor, throttle body, and lastly the intake manifold... plus unplug 20 or more electrical connections and several vacuum lines. 4 hours later and all of that out of the way the broken pump pops out in 5 seconds. I wish I had taken a picture but basically one of the ends of the pump connected to a hose had completely cracked off the pump, leaving the pump blades exposed. Got the new pump in and another 4 hours later the car was back up and running. Not a hard job, just a timing consuming job. Big thanks to Erik at I.P.M. Auto Service for getting the new pump out so quickly and guiding me through this repair.

On a related note, I've been having a problem in which I would have cruise control activated and it would buck back in forth while going down hills. It was like the car could not decide if it should increase or decrease the throttle input. You could watch the boost gauge and watch the needle just bounce around like it was doing some sort of dance. During the pump replacement I completely cleaned out the throttle body so I'm guessing cleaning the throttle body fixed the problem. Something to keep in mind if you run into a similar problem. *Update: Problem came back... so nevermind.

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