[rnmilnes]

I found a 20a receptacle on a 15a line. I have one additional receptacle that is not working at all and two others are showing power when I insert a tester but there apparently is not enough power to even turn on a single lamp. Is the problem because of the 20a receptacle?

 

[jmans8666]

Possibly it could be a loose neutral connection on an outlet

 

[DoctorWho]

Yeah, definitely sounds like there's a loose connection somewhere along the line, I'd just swap out that 20 amp for a new 15 amp to be safe. Make sure you don't leave anything plugged into the bad/weak outlets until you figure out the problem, any draw at all is going to create a potential for heat/fire at the loose connection.

 

[autx790]

You should not have a 20A receptacle on a 15A line to start with.

Also, could be a really funky installation. I had a receptacle that fed the lead to a second one. The second one didn't work at all, but the first one showed 110V hot to ground. However, nothing would turn on that i plugged in. I pulled it out, and here's what they had done. The hot went to switch one as did ground. The neutral went straight to switch two but wired at the hot terminal and a neutral wire was jumpered from switch one to switch two. I think the one who did that was on crack that day. So like jmans said, if you put a tester in the hot terminal and it lights up or you measure hot to ground and get voltage, but nothing turns on, sounds like you're missing a neutral connection in there.