my auxiliary water pump has begun making an awful noise while I have the ac on is this supposed to be on when the heater is not on or does it run with the ac too. and do i need to replace it or is there something else going on here I dont know about

 

Just a suggestion, if you'd put your year, make, model and engine size (SC or NA) we'd have a better perspective of what your dealing with and how to assist.

 

sorry thought I did that I'll fix that in the mean time its a 99 xj8

 

Cool....that pump should run all the time except with a low coolant temp or panel off mode. So are you sure its the auxiliary pump? It sounds more like the A/C clutch when its engaged on the A/C pump.

 

I was but now I think about it it only does it when the ac is on seems like it shuts off completely when I turn the ac off