The engine does not come off of idle (surging idle) when the gas petal is pushed, or the throttle position sensor (maybe wrong term) is operated by hand. This started after engine was jumped with a portable battery (the type with attached cables). Battery has been charged overnite and car still behaves the same way?

Disconnecting the battery for 5 minutes does not make a differance?

97 E320
3.2 engine M104 inline 6
White with gray interior
138000 miles

You have the M104 inline 6 engine.

I would sugges checking your OVP.

Two other items to check that affect idle quality (other than Vacuum leaks) are the mass air sensor and throttle actuator.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

Oh, oh, messing around with the throttle position on the 93-up (?) M104 engine while under the hood sets of the limp-mode. At least that's how I think I read it here one time. If I'm being a dope, please someone correct me.

But yes, mass airflow sensor needs checking

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1995 MB E320 Wagon
2001 BMW 530i
2007 MINI Cooper S (!)

Plus, I remember Steve Brotherton posting once that the only way to diagnose a bad mass air sensor is to trade it out for a new one. His shop keeps one on hand just for that purpose.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

HI Stephen, Ive seen several Mass Air Flow sensors damaged due to jump-starting, but never on a car as new as yours. Don't count it out though, just make sure you go over the basics first. And yes, miktvk is correct. Manually operating the throttle results in instant "limp mode". Good luck

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Sure does..

Disconnect the battery for a moment , hook back up and start
car
See if out of limp now