I have tried researching for the location of the ECT sensor, but no luck. Anyone out there knows where it is located on a 4 cyl. engine? I got the part, but cannot seem to find it! Any help will be appreciated!

 

It's In the cylinder head:

 

I appreciate the help! One question, where did you get the diagram from? Seems like it is impossible to get anything on a Sonata without having to buy a software or book. Thanks again!

 

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First off, just to clarify: your car's engine is referred to as an "in-line" four, or I4, as the cylinders are lined up in a row, rather than in two banks of 3 (V6) or 4 (V8). I don't want to sound like I'm nitpicking - that's how it is. 8D

Anyhow, according to Webtech www.hmaservice.com/webtech:
P0171 means the fuel system is running lean, which could well point to the MAP sensor (your car has one of these in place of a MAFS).
P1610 refers to a "CAN BUS OFF ERROR".
Exact text from Webtech:
DTC No. C1610 CAN bus off error [repair]
Inspect CAN bus wiring
Check the connectors C34 or C104, C94-4, C93-3

Probable cause
CAN bus cable open or short to ground or battery

I can't find P1101 on Webtech, but 1100, 1102 and 1103 refer to the MAP sensor.

I hope this helps!