SeanSerino

My original Comptech aftercooler pump/relay was dead, so I had to replace them. I got the replacement Bosch unit (forget the part number atm) but it should work just the same, according to the forums, and it's not much different than the Comptech supplied one.

So I swapped everything out, found a relay from Autozone which should be the same. I hooked everything up, and turned the car on. My pump was not on continuously, but rather, it was "pulsing". It wasn't a continuous flow; it would star/stop/start/stop, etc, every other second. I could hear the blade/turbine inside spinning and the coolant was flowing, as I could see when I opened the fill plug. It was working fine for ~20 miles. I just drove to work now, and I can't hear the pump, nor can I see the coolant flowing.

Anyone know if these pumps pump continuously, or do they pulse? I'm going to look at it again tomorrow. Guessing I may need to order another relay from Comptech, as I guess they use a very specific one.




Also, when I had the pump wired up before hooking it up to the coolant lines, it ran continuously. I only ran it for a few seconds though, as I didn't want to overheat i since it had to coolant running through it.

SIIK2NR

Is it possible you have air in the line?

SeanSerino

I don't think so. When I first installed it, there was some air, but after it ran for a few minutes, the air all circulated back to the main tank thing, and I kept topping off the coolant.

SeanSerino

I'm thinking the problem may be in the relay that I'm using. My comptech supplied one was dead, so I found the closest match at Autozone, and wired it up in a similar way. I emailed Comptech to see if I can purchase just their specific relay separately.

SeanSerino

Going to go outside on my lunch break and see if the pump comes back on. I'm hoping the relay isn't causing it to "pulse" and burn out the motor.

SeanSerino

Just reached in and pushed the pump a little. I could hear it click back on and run for a bit. THen when I let go, it stopped. I'm guessing theres a loose connection somewhere. Damn, now I need to take off the bumper again, which is such a pain.

SeanSerino

Can anyone verify if the pump should flow continuous or in a "pulse" like way?

CourageOO7

It should flow continuous. I checked the functionality of mine just the other day (into a bucket) just to see if it was working. I think your relay may be the cause of the discontinuous flow.

SeanSerino

I'm going to pull the bumper off tomorrow and mess with it, cause I have a bad connection right now anyways. It's weird because it ran continuous while it was not hooked up to the coolant system. I should try that bucket method. There was a very slight kink in one of my hoses, maybe that's the reason for the pulsing behavior.

It also could just be the way the Bosch functions, who knows. I don't mind the pulsing, as I did notice the coolant was flowing and the aftercooler was much, much cooler than usual; I just don't want the pump to burn out.

RAIN H8R

You correct, it is a continuous flow. I had a weekend full of beat runs and Im a bot upset because my IATs are still pretty high even with adding the SOS front mount heat exchanger.