Pontiac: Water pump replacement, air fuel ratio, crankshaft sensor

Question
I just got my water pump replaced on a 1996 pontiac grand am (2.4L).  Now my car seems to be running louder and with less power.  What is the process for replacing this part, does it affect my exhaust in anyway?  I called the shop and they said that they didn't have to remove anything pertaining to the exhaust.

Is this correct?  Can someone give me some ammo to ensure that I don't get charged for something that they didn't put back correctly?

Thanks

Answer
I do n't see any correlation between replacing the water pump and your current problems.

Take a look at the exhaust manifold and see if it possibly has a crack in it.

If there IS a crack in it this will cause driveability problems as the carck will be AHEAD of the oxygen sensor and the crack will suck in atmospheric air causing the oxygen sensor to sense a LEAN air/fuel ratio.

IF there is NO carck in the exhaust manifold, Then it is possible that when they removed the water pump some anti-freeze spilled down onto the crankshaft sensor or into the crankshaft sensor electrical connector of which will need to be cleaned out and possibly the crank sensor replaced.


Check for the exhaust leak FIRST and let me know WHERE the leak is.


Thomas