1991 300-SEL - M103 - 6 cyl

Check Engine Light comes on after idling up from a cold start in about 7 mins. Pulled the following codes:


13 - IAT - intake air temp sensor
22 - O2 sensor
31 - CTS - coolant temp sensor

Research reveals that not all of these may actually be defective. One or maybe two defective components could be causing all 3 codes. I'll have to dig.

I know where the IAT and O2 sensor are. There are supposedly 2 CTS' on this engine. One is for the temp gauge in the dash cluster; the other communicates with engine/fuel mgt.

Would anyone know if the part in the 2nd URL below is the sensor that communicates with engine/fuel mgt?

In my case - it's at the rear of the cyl head next to an engine hoist bracket. The elect. connector is 4-prong. Beru part number is 008-542-32-17-M47 - found in 1st URL on the right side of screen along side of part.

http://www.pelicanparts.com/catalog/SuperCat/3371/MBZ_3371_WATMIS_pg2.htm#item1

http://www.pelicanparts.com/cgi-bin/smart/imgdsply.cgi?pn=0085423217-M47







Thanks for your time.