I have an e320 wagon that I'm noticing a tap tap tap and vibration when I hit the gas from a stop. It doesn't seem to be there when cruising or even accelerating later. I've only noticed it on take off.

Any ideas what this could be?

Background on the car, bought it used fixed an exhaust leak changed the MAF sensor, put new tires on it. Seems to run good.

It was rear ended at some point. It doesn't look bad but I know the frame is bent a little bit. I can see a small crease in the roof metal between the two doors (front and rear) also the doors close a little tight. So I'm sure there's a little bend in the frame from the rear end collision. It drives fine and straight. But maybe this could be related maybe not.

What should I be checking?

thanks!
Nick

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-E300d '99 350k
-Suburban '93 220k
-TDI Jetta '03 350k
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-F250 '96 7.3
-Dodge Ram 12V
-E320 '95 200k
-E320 Wagon 1994 155k
-300d Turbo '87 187k miles
-E320 1994 200k
-300d Turbo '84 245k (sold to Dan62)
-300d Turbo '84 180k
-300sd '80 300k
-7.3 Powerstroke Diesel 15P Van 500k+ miles
-190d '89 Non Turbo 2.5 5cyl 240k (my first MB)
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