water pump replace now rough idle

2000 alero 2.4 167000km

just replaced the water pump now car has a slight miss at idle seems to run good at speed was wondering if the timing chain has skiped a tooth would it not run bad all the time? no lights come on but noticed the exhaust smells like rotten eggs (did notice the battery light come on once)

Pull your trouble codes.

I don't see that there would be any connection between replacing your water pump and the timing chain slipping a tooth. That's not a common problem with these engines that I'm aware of.
Your problem is more likely related to a vacuum line or electrical connector you may have disturbed during the water pump replacement procedure, although other things are possible. Like taillights suggested, you could get someone to scan your computer for possible trouble codes even though you're not getting a light. If you don't have a scanner, your local Autozone or equivalent can scan for basic codes and won't charge you to do it.

ill check for codes tonight the reason was wondering about the timing chain is becuase you have to remove the tensioner to remove the chain from the drive gear on the pump it drapes over the cam gears so not worried to much about that but was wondering about the crank gear

Sorry, I was thinking about the water pump installation on the 3.4L engine. I didn't realize you had to mess with the timing chain on the 2.4L engine to replace the water pump.

ahh np got it fixed there is enough slack on the chain that you can loose a gear on the crank when you retighten the tensioner took it all apart and retimed i was actualy out 2 teeth amazing did not damage anything now runs like a top tks for the advise