1994 850 turbo wagon
knock sensors replaced and code continues to come up. Any suggestions?

I had my knock sensor replaced a couple of months ago at an independent
Volvo garage & it works just fine. Volvo has a special repair kit(I'm sorry,
I don't have the part number). Evidently, this is the second repair kit from
Volvo to fix this problem. The first kit did not work. I'm wondering if you
got the first one? The cost of the part is about $90 but it's a lot of work
to replace as the manifold has to be removed in order to access the sensors.
Total cost part + labor--$350. The mechanics said the second repair kit looks
different than the first so maybe you can use that info to get the correct one.
My car is a '94 850 turbo wagon with 87K miles.
Good luck--Don in Denver

Yep, in '94 850Ts the problem is NOT really the knock sensors, it's a problem inside your fuel ECU. Get a used ECU (~$250 if you can find one) and the problem will be gone. It's a unique problem that I've seen with many '94 850Ts over the years and EVERY time it's cured completely with another ECU.

Will an ECU from a '95 turbo work in a '94? (To avoid having the same problem again.) I'm at the end my patience with my CE light. It's on every other day.