2007 Prius Code P0171

Can not. And you have to T in to the fuel line to measure pressure. But you can live data the A/F sensor and MAF easily. The ambient temp thing could be pointing at a metered air problem but I believe typically it's cold air that triggers lean codes. I'm somewhat serious about suspecting fuel pump straight away with Gen 3 P0171 and/or P3190. I think with Toyota across the brand, P0171 is most often the A/F sensor but not so sure with Prius. You see very spotty reports with Gen 2 and almost nothing with 3, although it could be the 3's just aren't old enough yet.

And JC has been doing awfully strong work around here lately so maybe you should just shotgun the MAF while you're at it.

Sorry for the thread derail @llg . I'll stop now.

 

I believe The Hybrid Shop of the Carolinas is there. Decent, knowledgeable staff.

Not that you need to go there for this code or issue.

I would start at the MAF sensor and go through process of elimination after that.

Good luck.

 

I think you can get a lower priced Denso part from Amazon, it's the same as what you would get from Toyota.

Last time when my MAF sensor was questionable, I tested the part on my other car first (electronic parts are not refundable). I switched the MAF sensor with my other gen2 car. After I switch the MAF sensor, the problem went to my other car. I ended up taking one from a wrecked car that was in my possession. But normally you can probably find an OEM used one on Ebay or wrecking yard for about $25.00. Since this part is fairly cheap, I would try to stay with the OEM Denso part. I would say the failure rate on this part is fairly low so a used part won't be too much of a gamble.