While trying to troubleshoot a P0171 code, I noticed two hoses were not connected to anything. Was wondering if anyone knows where/what these hoses are suppose to be connected to. (see pics below)

I've looked all over the engine bay and can't seem to find where/what they connect to.

 

well the first picture is a vent line that goes back into your intake, which isnt a big deal to not have hooked up as long as the intake itself doesnt have a provision for it. You could run a catch can setup for that line if need be. And the second picture is one of the lines for the factory electronic boost control solonoid, which if you have a manual boost controller or a 3 port that shouldn't make a difference either.

 

Would either of those throw a P0171 CEL?

 

Given that both of those connect to the intake snorkle and the snorkle isn't there, it's not surprising that they aren't connected.

Please tell us you haven't been driving with no intake (and, therefore, no MAF).

 

well if you really have no intake tube connected to the turbo then yes it could because like iowa posted you most likely don't have a maf sensor hooked up and that's kind of important to have functioning on the car........

 

if you have a vac leak I think it throws p0171, because I think that is the code for LTFT +/-15%

 

Um, folks. If he doesn't have a MAF, he'll get that code. No need to start looking for a leak.

 

Of course I haven't been driving without my intake. I took the intake out while I was seraching for potential leaks and noticed these two hoses were not connected. Plus if you start you engine without the MAF detecting airflow the engine will cut immediately.

Also my intake came without the bung so those hoses are just venting to air. I was wondering if those would throw a P0171 CEL.

 

Of course you can throw a P0170 with the PCV hose just hanging there. You're sucking in unmetered air at idle (and any other time the intake manifold "sees" vacuum).

ps. my car will run with the MAF unplugged (albeit in some sort of limp mode)

 

When first got my evo, the short ram intake was already installed (used). I drove it for a year and got a CEL once or twice but they were short lived. After a year I decided to clean the air filter on the intake using the AEM air filter cleaning kit. By mistake I oiled the filter and a couple days later I got a CEL. After reading online I shouldn't of oiled the filter as it was throwing off the MAF sensor. So I pulled the MAF sensor, cleaned it with MAF cleaning spray cleared the coded.

The CEL came on again a couple days later then went off and didn't come back on until the weather got cold. Whenever it was above 80 degrees F outside the CEL didn't come on. Anytime it got below 70 F outside the light would come on. So I decided to clean the filter again and NOT oil it this time. I also cleaned the MAF. Cleared the CEL and was good for two days and the light came back on again, P0171. Now I'm at a loss, can't seem to find a leak anywhere as I was able to run the hose venting to air for a year without any problems but not anymore.

I did notice that the driver side hanger on my AMS exhaust broke and there is a small hole before the exhaust tip. Not sure if that could throw the code?

 

How much unmetered air you are sucking in through your PCV system (assuming that you've never had the larger hose connected to the intake snorkle) depends on a lot of things, one of which is ambient temp. So, it's not completely surprising that the CEL is temp-dependent. Just do something to attach that hose to the intake (post-MAF) and the CEL is likely to go away. But don't do this just to get rid of the CEL; do it because having a source for unmetered air to get in the engine - even if it's only open when not in boost - is a bad thing.

 

Gotcha, with my set up its prob cheaper to get a catch can or new intake pipe? Or install my own bung?

 

I have no strong feelings (nor much expertise) on crankcase ventilation. My highly modified car had a catchcan (along with complete emissions delete); my lightly modified car does not (and still has a cat).

 

Of course today, OAT is 75 F, the CEL light went off. Guess today would be a good day to get my state inspection...