Gen-1 2002 Because I have a P0171 and have already replaced the Mass flow sensor, I assume I have a vacuum leak somewhere. I'd like to replace all the vacuum hoses but I'm not sure which or where they are. Can someone please help with a diagram, youtube video or something that will show me which are my vacuum hoses?
<Bump> on the P0171 code. Here is some information on how MAF sensors work, and how they fail. Not sure if this will help in your case, but it might give you some ideas on where to look for possible faults. Mass Air flow Sensor (MAF): how it works, symptoms, problems, testing Good luck!
There is a schematic vacuum diagram under the hood. Your typical mechanic (or auto parts store person) reading a P0171 will tell you that you need a new upstream O2 sensor. That is, of course, not necessarily the case, but frequently is. In other words, the normal assumption isn't a vacuum leak, but a bad sensor. Both assumptions are ... well, assumptions. Do you have a scantool with which you can get live data from your O2 sensors? P0171 just means that the upstream O2 sensor is getting abnormally low (lean = too much air) readings. It can come from vacuum leaks or a bad sensor. But it starts with getting some data. And as far as vacuum leaks go, don't count out the intake manifold.
I'm not sure if this is a problem. I doubt it because I've already replaced this once. Unless I got a bad part.
Hey thanks so much for that! I just plugged in my scan tool and it seems as if one of the oxygen sensors are acting normally but I'm not sure what the other one is doing. Does this look normal to you?
There's nothing wring with an O2 sensor reading of .86, but it's not static. You would need to be able to graph it. The O2 sensor should be constantly bouncing up and down between about .1V and .9V I tried to post a pic, but it won't work. See: OXYGEN SENSORS: HOW TO DIAGNOSE & REPLACE
