Not an expert, just intimately familiar with the systems on OUR 190E that I have worked on. Anyway, the only mini shock at the front of the engine is a drive belt damper, attached below the fan from the alternator bracket to the idler pulley. It can be loose and noisy, but should cause no driveability issues.

From your symptoms, look into cleaning the idle control valve or resoldering the contacts inside the OVP relay as possible cures. But, if you work on the ICV, you should pre-order ALL the rubber air hoses attached there, the intake manifold, and the breather circuit, as they will be hardened, leak at couplings, and will likely break on removal. The OVP is behind the access panel that is behind the battery, id'd by having a fuse on top.

Steve

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'91 MB 190E 2.3
'08 RAV4 Ltd 3.5
'83 Lazy Daze m'home 5.7