new to me, 1991 560sel with 81,xxx miles

I am 3 rd owner, not much on service history on vehicle sadly.

problem one,

at times, she runs / drives and idles great, at times a sputtering / hiccup on cruising and at idle..... electrical or fuel side ya think ??

problem two

a very soft / spongy ride. had all the hydraulic lines replaced recently , the nitro accumulators too. that solved the saggy rear.

I m guessing front shocks are spent , any symptoms on failed rear shocks ?

thanks for all the help

__________________
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'91 560sel 81,xxx miles