This is more of a curiousity than anything. My truck used to get at least 15 if not 16 mpg city highway mix. Lately it is getting about 13-14 mpg.

Which sensors have the most impact on fuel economy? I'm thinking that the aftermarket brands may not be nearly as tight on their tolerances.

I have had a Cardone Select I believe its called replacement mass air sensor from Advance Auto on my truck for a few years now. I'm wondering if it is really accurate enough or if a real Ford one would really be better.

I also had a BWD TPS, well my truck did not like that. The code was 122 if I remember right. Which was TPS at or below minimum voltage. I put a Motorcraft one on and it seems to like it alot better. I also tested resistance on each one and the Motorcraft one has slightly less resistance at idle and wide open throttle.

I'm also going to replace an Autozone brand ECT sensor with a Motorcraft one. I know that I never should have put that A'zone junk on there.

I'm fairly sure everything else is Ford, excpet for the O2 sensor which is Bosch which I have read many times is not any different than the Ford one, which is actually a Bosch sensor.

 

It wouldn't surprise me if alot of cheaper replacement sensors are of lower quality, although sometimes its the other way around and its the same product, just different packaging. although I would generally lean towards spending more on sensors such as your MAF sensor, since it has a lot closer relationship with the computer than sensors like the ECT sensor is. the MAF takes a bit more to test to make sure its working properly as well.

it would be interesting to know the origins of the different brands, but I wouldn't necessarily start pointing fingers at their accuracy first. the list of stuff to check before that is a mile long...