I am planning to replace all four O2 sensors on my C43. The Bosch universal part# for all, before and after CAT, is 15738. My question is, are the sensors all the same. How come Bosch has separate part#'s for all four, 15088, 15090, 15092, 15094. I know that the universal needs to be spliced, but other that that, what's the difference? The universals are much cheaper.

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1991 190E 2.3 SOLD
1972 911t 2.4 owned since 4/80 300,000+ miles SOLD
1999 C43
Merlin XLM, All Ti, 17.5lbs.