tiny rubber hose came off = LOTS of CEL codes!!

So, wifey and I went on a trip to the north cape with our OBXT. Enjoyed the ride and the crazy weather. On our way back, stopped to fill up tank (150 bucks ouch). Before I turned off the engine, I suddenly noticed a rough idling. I was like "mmh that should go away :confused:". Filled up the tank, started the car; still rough idle; left gas station and 100 feet later, CEL light+ cruise control started flashing. -----> Panic!!

Turned around, went back to the gas station. checked my 'torque application' installed on my phone and pulled 4 codes!!!! one for each cylinder misfiring.

I stayed calm and checked the engine bay. took off cover. looked around. Was not sure what to look for frankly until I remembered reading on this very forum about checking for loose rubber hoses whenever you get rough idling; especially the one underneath the intercooler. Well THAT was the one. Came completely off. Took a few minutes to put it back. Unplugged battery, checked oil, fluids etc...And boost was back to normal+no more crappy idling :spin:

Dang, If I hadn't learned that info on this forum I'd be toast in the middle of nowhere!! Thanks fellow LegacyGT forum users.

Right on brother, I am always happy to hear a good story among all of those that involve disasters. Zip ties and silicone hoses will be your friend. Think about swapping out some of those old hoses!

Right on brother, I am always happy to hear a good story among all of those that involve disasters. Zip ties and silicone hoses will be your friend. Think about swapping out some of those old hoses!

 

Definitely! I will check the hoses if they're still in good shape and will zip tie the ones without clamps asap. I am indeed surprised that this very rubber hose did not come with a clamp.

Yup, had the same problem once, luckly I was close to home to find the issue. A few zip ties and small hose clips fixed that problem.

 

+1 for the Forums.

luckly I was close to home to find the issue.

 

^ I was 8 hours away from home . But we managed!

That would scare the chit out of me too, being that far away and having car problems.

glad to hear everything worked out, Subaru should really consider redesigning that, i've had countless problems with vacuum leaks, but learned from them haha

good to know I will check mine out and see if it's ok just in case. Thanks for the heads up.

glad to hear everything worked out, Subaru should really consider redesigning that, i've had countless problems with vacuum leaks, but learned from them haha

 

^ +1 on Subaru redesigning them.

 

good to know I will check mine out and see if it's ok just in case. Thanks for the heads up.

 

^No problem. I am glad this may help others.

glad to hear everything worked out, Subaru should really consider redesigning that, i've had countless problems with vacuum leaks, but learned from them haha

 

It was redesigned in 07-08 note the same tube has no T fitting, just straight to the manifold- there was a turbo vac line change as well.

 

 

 

 

however it still popped off mid-tune for me.

It was redesigned in 07-08 note the same tube has no T fitting, just straight to the manifold- there was a turbo vac line change as well.

however it still popped off mid-tune for me.

 

^well, that's the problem. IMHO, part of the redesign should be some kind of clamp to hold the vacuum hose in place. This way, no more pooping. oops, popping .

North Cape - that's literally nowhere... And a place where the weather is tricky and mosquitoes are aggressive.

North Cape - that's literally nowhere... And a place where the weather is tricky and mosquitoes are aggressive.

 

^yep you got that right. And car is from Utah . We even camped with nasty (or normal I guess) weather.

Sucker is now zip tied. Should not need to worry about it anymore.

What exactly is that hose?

 

I had a similar story on a long trip. After my wife filled the tank in the middle of Southern Wyoming we got a CEL. Of course we were very worried but were stopping for the night anyway. Before going to bed I'd remembered reading here that if you don't tighten the gas cap all the way you can get a CEL. So, I went out, tightened it and drove around a bit. Sure enough, it was gone!

Out of curiosity what were the codes you got when the hose fell off?

"tiny rubber hose came..."

 

LOL I just had to...

Out of curiosity what were the codes you got when the hose fell off?

 

^P0301 Cylinder 1 Misfire Detected

P0302 Cylinder 2 Misfire Detected

P0303 Cylinder 3 Misfire Detected

P0304 Cylinder 4 Misfire Detected

 

Actually, 2 of them were reported while the other 2 were pending. Still freaked me out especially on a road trip.

 

What exactly is that hose?

 

^ I believe it is a vacuum hose that is connected between the manifold and the air by-pass valve. I think it is hose number 12 on the figure attached. Anyone correct me if I am wrong. Currently learning all that stuff.

You are correct, hose #12 connects to the "T" fitting which is not shown in the diagram. Also, if one of the small hoses in front of the manifold comes loose you'll also get the same codes.

You are correct, hose #12 connects to the "T" fitting which is not shown in the diagram. Also, if one of the small hoses in front of the manifold comes loose you'll also get the same codes.

 

Cool. Good to know about the other hoses.

I believe the hose is responsible for keeping the bpv closed while on boost, one you let off the gas, and vac is created, it opens the bpv and releases charge pressure on the compressor side of the turbo/throttle body. If it's disconnected you will not hit target boost, it will just bypass once the valve opens under pressure. It will also cause a massive vac leak and your idle will go to sh!t.....with potentially some misfire CEL's.

Cool. Good to know about the other hoses.

I've learned the hard way myself, after taking things apart and missing to reconnect one of those pesky hoses. Then 4 miles down the road CELs start going off. "All hell, what now!"

I believe the hose is responsible for keeping the bpv closed while on boost, one you let off the gas, and vac is created, it opens the bpv and releases charge pressure on the compressor side of the turbo/throttle body. If it's disconnected you will not hit target boost, it will just bypass once the valve opens under pressure. It will also cause a massive vac leak and your idle will go to sh!t.....with potentially some misfire CEL's.

 

^And that's exactly what happened to me. It kinna ran fine but I could sense my boost was weak or something. And then, as soon as I idled the engine, that was it!

Good explanation. thanks.

 

I've learned the hard way myself, after taking things apart and missing to reconnect one of those pesky hoses. Then 4 miles down the road CELs start going off. "All hell, what now!"

 

:lol:

Reviving my old thread. I did ziptie the vacuum hose that came off the T connector underneath the TMIC about a year ago. Then last Saturday, I noticed I no longer had boost+crappy idling+a hissing sound at idle as well. I was like .

Anyway, long story short the hose on the OTHER side of the T connector came off . This time, I had to take off the TMIC so that I could reconnect and zip tie that sucker as well. Now it's zip tied on both sides dang it!

Don't worry, some other vacuum hose is bound to pop off in another year.