Thread: need help with surging engine.

Do you have and Check Engine Lights on? If so, get them scanned and either let us know what they are or look them up. My car did similar things when I had a vac leak...but getting your car scanned is your first step.

Did this start occurring after any work/maintenance?

Sounds like a big Vac leak. That would be your sucking sound... Get some starting fluid and spray it around parts of the engine and you should be able to tell where its coming from when the idle changes.