Originally Posted By Alexdodge
So where is this upstream sensor located on the 05 4.7 engine


Gonna be real honest here, if you don't already know this then this job is probably not for you.

You have two upstream O2 sensors, one on each side of the engine, they are UPSTREAM of the cats. Think about how the exhaust flows and which direction is upstream.

Without a scan tool you'll be guess which one, if any, of the upstream sensors is bad. may as well replace both rather than one of them if you're going to do it.

Which, at this point, you are just throwing parts at a maybe problem.


They say there are no such thing as a stupid question.
They say there is always the exception that proves the rule.
Don't be the exception.