At low RPMs my 1987 190e 2.3 8v sounds very old and putt-puttish. I'm assuming it's not the engine, but mearly an old exhaust system. What should I replace to improve the sound? Would only a new muffler cure this?

First you need to find the hole thats causing the noise...that way you can figure out what to replace. It could be any exhaust part from header to muffler.

I have a similar sound and i always concluded that the put put sound is caused by the restrictive exhaust system of the car. I would recommend just getting a custom exhaust from headers the rear muffler. If you don't want to spend that much money, just replace the catalitic converter with a high flow one and the two mufflers with higher performance ones and that sound should be gone and you will have a nice free flowing system.

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George Carstens

Brothers of the Benz,
I have a 1987 W124030 with 188,000 miles still with the original exhaust system!
Is your putty putty coming from the exhaust outlets at the rear of the muffrler, or from under the chassis?
A smooth even puur should come out the tailpipe(s); if putty putty them you have unequal combustion in one or more cylinders accompannied with a slight roughness in the idle.
If coming from elsewhere by getting under the car with the engine running will give evidence where the exhaust gases are leaking.
Use a heavy rag and stop up the outlet causing high exhaust pressure and the leak quite apparent.
Happy Trails Beep Beep Purrrrrr from The Spiderman in Houston!!!

I think it's putt putty out the tail pipe, and the idle is kinda rough, so how do I fix the unequal combustion??

Brother of The Benz, LucasBraden
Putty Putty from the tailpipe normally is that one or more cylinders is on for a free ride,i.e. it isn't producing it's share of the combusation process.
Naturally the easiest test would be a visual of the spark plugs and while removed a cylinder compression test.
You should do this as soon as possible for not only will the valve face burn away as the combustion gases leak past an irregular valve seat, but the seat in the cylinder head too will eroide.
Do some testing before severe damage occurs.
Happy Trails Beep Beep from the Spiderman in Houston!!!