2001 alero 3400 rough idle at start

[gnuiver]

2001 alero 3400 140,000 miles. Is has start to run rough on start up. It clears up right away, but don't know the cause?

[gnuiver]

Code is now showing as camsensor issue and the ever present EVAP issue, I gave up on that one. Changed the valve twice and still have the issue. Changing cam sensor tomorrow will see what it does

[unchained01]

Hope that takes care of it. You ever present evap code could be caused by a lot of things in the system. The best way to tackle those are a smoke test

[gnuiver]

Smoke test? help me out here. dont know that one

[unchained01]

There are videos on you tube. Search evap smoke test. It will give you an idea. The smoke machine is used to find leaks or sticking valves etc Evap codes can be anything from a faulty gas cap. Rusty filler tube , a hard Line that's rusted thru. Any hoses may be cracked, charcoal canister that is plugged or broken. Hope that helps alittle. Also be careful with the sensor. They are known to swell and be cracked with heat and age Check the wires thoroughly There are some who have found them faulty also