Do I need any special tools? How Hard is it?water pump 2002 aztek

If the housing is leaking, you can replace the gasket but you need to remove upper filler panel, air cleaner assembly, secondary air injection control valve, oil level indicator tube nut, water pump belt shield, the belt, the radiator hose at housing and then the cover.
If you need to replace the water pump, not easy as you need a special tool to remove and insert the pump.

Depends on if this is a 3.5L or 4.0L. The 4.0L is located on the driver side inside the water jacket. You will need a special tool to remove it - it is internal. Not too difficult of a job, and Autozone will rent the tool for free.

you have to take belt off need special wrench.

special tools you need EN 48543 FAN CLUTCH HOLDING TOOL. J41240 FAN CLUTCH REMOVER AND INSTALLER. TORQUE FOR FAN CLUTCH NUT 41 LB FT. FOUR BOLTS TO FAN BLADE TORQUE 20 LB FT.WATER PUMP BOLTS TORQUE TO 11 LB FT. DONT NEED SPECIAL TOOLS REMOVE WATER PUMP.

Here is the complete procedure to replace the pump on your 99 Deville.
You will need to purchase the special water pump removal/installation tool.
1. Drain the cooling system.
2. Remove both radiator hoses
The water pump is on the right hand side of the engine and is driven by a pulley that comes off of one of the overhead cams.
3. remove the air cleaner assembly.
4. remove the pulley guard.
5. loosen the tensioner and take the belt off of the pulley.
If you decide to replace the belt you need to remove the tensioner, remove the studs that the pulley guard came off of and the tensioner will come out.
6. remove the water pump housing cover. the thermostat housing is bolted to this cover. it has (4)10mm bolts that hold it on.
7. using the special tool, turn the water pump clockwise (it twist-locks into the housing) and remove it.
8. clean all sufaces, replace both o-rings.
9. CAREFULLY! install the new pump with the special tool. be careful that you turn it all the way in counter-clockwise but that you don't pull too hard. The pump has steel tabs that lock into grooves in an aluminum housing. if you damage that housing by forcing the pump too hard you will cost yourself a ton of time and money.
10. re-assemble the engine in reverse order as disassembly.
don't forget to use your torque specs. You are working with aluminum castings

I have never heard of a car that changing the water pump requires access to the timing chain. Just the wreches.

If You Only need to replace water pump, you need a special tool to hold water pump sprocket in place while changing the pump, Just look up GM 2.2 Water pump tool on e-bay, or ask a local auto parts store if they rent one out. Garages make out like a bandit to replace these water pumps, because you need this special tool to do the job, and ti is impossible to do it without . Good Luck

well if your talking about the 4 cylinder 2.2 liter,,youre gonna need a special tool that saturn has,its a holding fixture tool for the timing chain because the chain drives the water pump and you must remove the water pump pulley from the pump but you must keep the chain in place with this holding tool,it keeps the chain and pulley in place,,,,youre gonna have to find that tool either from the saturnvservice shop or maybe aftermarket,the only other way to do it is remove all the timing chains and then remove pump,,,,

Water pump is located on rear of the engine. faceing the car it is between the radiator and the head. It is driven by a small belt. It is removed by removing a cover plate that has the radiator host and by pass hose connected to it. it takes a special tool to remove and install this item. it is available at most auto stores. approx. 2 hour job and somewhat a hard job . see the haynes manual for this car very detailed on how to change the waterpump. jim

It's time-consuming, as requires removing aux drivebelt (with alternator etc on it), and the cam belt. Well worth replacing the cam belt, aux belt and crankshaft oil seal while there. It's quite hard, but no special tools needed - except the Honda manual/instructions for setting up correctly (unless you mark the belt and replace exactly on pulleys).