01 grand am rough idle

[LoMbArD]

I have an 01 grand am w/ the 3400. i have 201k miles on it. about 10k miles I gave it a tune up, (plugs, wires, etc) This morning on my way to work when I stopped at a light it started shaking. It was idleing really rough, almost like it was missing on one cylinder. As soon as I am above 5mph it runs great again.

[3100]

is your rpm fluctuating when that happens?
give more details when this happens. Every day? Only when engine is warm? etc........

[LoMbArD]

I first noticed it on my way to work this morning. I drive about 100 miles a day. I live about 25 miles out of the city and I didn't notice it this morning until I got in town and stopped at a light. It normally idles around 600 RPM's. When it's idleing rough the tach moves just a tiny bit, like maybe 25 RPM's if that. Barely noticeable. It ran great above 1200RPM's, but when I came to a stop, both in park and in any gear.

[xeroinfinity]

Sounds like a misfire situation. Did any of the service lights come on when this happens ?

Might double check your wires and make sure they are all tight.

[3100]

and vacuum lines for leaks.

[LoMbArD]

thanks for the suggestions guys. The SVS light has been on for several months, but I am 99% sure that's because one of my headlights and one of my fog lights are out. I almost never drive at night so haven't remembered to replace them yet. As soon as it stops raining here I'll check my wires/vacuum hoses etc.

[FromTheInside]

yeah, SVS is stuff like your lights and SES are your sensors, engine, and transmission.

[LoMbArD]

OK found the issue. Therer was a hole melted in the back of my rubber PCV elbow. Not quite sure how that got there but I replace the PCV valve and the elbow and it's back to running normal now.

[xeroinfinity]

Glad you found it and was an easy fix !

Yes SVS is none critical stuff, like your high heams(not your fogs). And a maybe a few other problems would trip this too.