replacing timing belt and water pump... what else can I replace while I'm there?

[HardTech]

purchased the car about 5000 miles ago, and I've done the following:
- spark plugs
- distributor cap and rotor
- Z4 shifter
- oil change

the air filter does not need replacing

I have a new fuel filter sitting in my garage. I plan on changing out the fuel pump, but is there anything else I could change while I'm in there?

edit: the car does have a slight rough idle when it's warmed up, and there's hesitation when in 1st gear with a cold engine. I'm hoping to get rid of both problems

[Danny]

Valve cover gasket?

Thermostat.

[HardTech]

Valve cover gasket?

Thermostat.

good call.. I need a new valve cover gasket. If my thermostat is working fine, should I replace it anyway?

[bddog]

I put a thermostat that fails open in mine. New tensioner a must.

[HardTech]

what's a tensioner?

[bddog]

Assuming you are replacing the timing belt in a six cylinder E30. it keeps tension on the belt. Not expensive. If you don't replace it when installing a new belt, and it goes bad, you will be very, very unhappy.- Steve

[bddog]

PROBLEM SOLVED: It was a faulty tensioner. I took off the timing belt and the tensioner pulley had about .020 thick of rubber in a wavering pattern on it from 15 seconds of the car running. Its axis was obviously not perfect. You could spin it and the rubber on it would run back and forth. It was throwing the belt back and forth causing the noise. One of those random things I guess.
Got a new belt and tensioner and installed... all is well... except now i have a stumbling issue when the car warms up. I love my E30.

Check out the problem Bimmerboy12 just had with a NEW tensioner on General Technical- Steve