So my check engine light on my 92 300 E went on the other day, and I'm lucky enough (or unlucky) to have the California model with built in LED on the OBD system. I read the fault codes (3, 28, 29) which seem to indicate the following:

(3) Engine coolant temperature signal read by CFI control module

(28) Intermittent contact in engine coolant temperature sensor circuit

(29) CFI and ignition control module reading different engine coolant temperature

It sounds like a loose wire possibly, but, I'm looking for some advice before I just start diving in and mucking around without having a sense of where to start. I replaced the Engine Temp Sensor (attached to the block of the engine near the back wall of the engine compartment) about a year ago, without issue. Any thoughts?

Thanks in advance.