Water in the Gas!
Looks like this is it guys.. thanks Ken! You're esteemed remote diagnosis has also been corroborated by another forum....I'll keep an eye on it and run through with an additive as you describe.
1984 W123 230E Saloon/Sedan! (82k miles - Ice Blue as new)
1985 W123 230TE (96K miles - stinkingly nice!)
1995 W124 E320 Wagon (130k miles)
Sportline Suspension W124, W123 TE restoration, A/C, cruise & powered seats retrofit!
>Based in the UK!