Hi Group:

Anyone with an 850 Turbo have any trouble with an aftermarket ECT (coolant temp sensor), such as from FCP Groton? When the original part failed I replaced it with the FCP Groton part, and now I'm getting an A2-123 fault code, and the coolant fan runs inappropriately (way too often, and for way too long), although the coolant temp gauge apparently works fine. The fault code appears after about 5 minutes of starting the cold engine, followed by the engine running progressively rougher as it warms, as if running too rich. Restarting the engine after such an episode is also nearly imposssible, again suggesting an over-rich mixture, but the engine always starts immediately when cold.

Is this one of those cases when only the OEM part from a dealer will suffice? Thanks in advance.

Regards,

Dean

I doubt the ECT sensor is the problem. Sounds like a sticky or defective relay to me.
--
'88 240, '92 745, '98 v70 John, Tampa Bay

What does FCP say about it?

FCP said to send their sensor back for credit ($30), which seems very fair of them. Just installed a new OEM sensor from the dealer (such a deal, at only $75), and it works fine. FWIW, both ends of the connector between the sensor and chassis wiring were tight, and very clean and shiny, so I'm sure corrosion wasn't an issue. Now there are no fault codes, the fuel mixture properly leans as the engine reaches operating temp, the radiator fan works appropriately, etc., so the problem is solved. It would have been interesting to compare resistance measurements between the two sensors at various engine temps, but I just wanted to get done with this job and let my wife have her car back. I also had the pleasure to pay $8 (really, $8!!) for a thermostat seal at the dealer, rather than $0.50 anyplace else.

Dean