[B Feelgood]

So I've been getting the P2C57 CEL when going full throttle. If I just go part throttle, I could drive around all day without the CEL coming on. However, as soon you you put the gas pedal to the floor, the car goes into limp mode and throws the CEL along with the reduced power engine malfunction warning.

Being that this code references a boost leak, I hooked up a boost leak detector that I made and pumped some air into the system. Immediately upon doing, I could hear air gushing out from the pipe that the boost leak detector is attached to. If I push this pipe in towards the firewall and hold it there, the air noise stops and it seals. (see YouTube video below)

Obviously I found the cause of my CEL but the problem is that I can't see or even tell where that pipe connects to as its buried in the engine. Has anyone had this same failure before? What does this pipe attach to and what's the best way to go about gaining access to it?

[B Feelgood]

Found a diagram that looks like this pipe attaches directly to the turbo inlet?

[mojobmw_e90]

But in the video yes that is the intercooler pipe that's connected to the turbo directly

[B Feelgood]

Correct, in the picture I'm pointing to the turbo inlet pipe that the boost leak detector is attached to with eh intercooler pipe to the left of it. However, I see no way of gaining access to removing this pipe. Are there o-rings/seals that hold this pipe onto the turbo or go just a clamp?

[weehe126]

I doubt that is the reason for your boost leak since it is before the turbo. It doesn't see boost. If you really want to take it out to check, there is one screw holding it in place on the right side. Check your charge pipe and intercooler plumbing for obvious leaks.

[B Feelgood]

Thanks for responding. Wouldn't a huge leak here be drawing in unmetered air? It sounds like there is one bolt that holds that pipe on and then it just pushes into onto the turbo inlet?

The dealer originally stated it was the charge pipe that was leaking so I replace that already and then verified it wasn't leaking.

[B Feelgood]

Correct me if I'm wrong but it looks like there is just one bolt on the top of the pipe and then the bottom half simply pushes onto the turbo outlet with no other bolts/clamps? The only thing holding it onto the turbo inlet is force/pressure?

[Sgop335]

Originally Posted by B Feelgood

Correct me if I'm wrong but it looks like there is just one bolt on the top of the pipe and then the bottom half simply pushes onto the turbo outlet with no other bolts/clamps? The only thing holding it onto the turbo inlet is force/pressure?

Video shows intercooler hose, pic shows inlet? Nice shoes btw

[B Feelgood]

Figured it out, haha. It just pushes into the turbo inlet with force and there's one bolt at the top of the tube to stabilize or keep the pressure against it.

[mojobmw_e90]

That rubber gasket that connects to turbo is replaceable

[B Feelgood]

Originally Posted by mojobmw_e90

That rubber gasket that connects to turbo is replaceable

I reinstalled the pipe back into the turbo inlet, tightened the bolt at the top, and hooked up the air pressure again. As soon as I run 5-6 psi of air, that pipe backs off of the turbo inlet and create a huge leak.

Isn't this the best place to test for leaks on the N55? If so, how do I keep that pipe from popping/backing off of the turbo inlet whenever I induce air pressure into the system?

[weehe126]

there really isn't a good way. best bet is to take the turbo outlet off and test from there. But is hard to get in there

[mojobmw_e90]

Buy a new gasket, make sure u clean the turbo inlet with break cleaner so it cleans up oil and such, spray some hairspray on the new rubber gasket and give that a shot. Air spray becomes tacky when it gets got and dries up

[weehe126]

Guys you will never get it to hold pressure. This piece only needs to support vacuum, air being sucked into the turbo. I guarantee you do not have unmetered air getting in unless the gasket is damaged severely. The leak is somewhere else.

[kfriceman]

Originally Posted by B Feelgood

I reinstalled the pipe back into the turbo inlet, tightened the bolt at the top, and hooked up the air pressure again. As soon as I run 5-6 psi of air, that pipe backs off of the turbo inlet and create a huge leak.

Isn't this the best place to test for leaks on the N55? If so, how do I keep that pipe from popping/backing off of the turbo inlet whenever I induce air pressure into the system?

No shit, because this is the inlet side and does not see positive pressure......ever. This basic turbo plumbing.

-Kevin

[B Feelgood]

Originally Posted by kfriceman

No shit, because this is the inlet side and does not see positive pressure......ever. This basic turbo plumbing.

-Kevin

Kevin, I am new to the 335/N55 and was simply following the instructions in the thread below. I am assuming that maybe the reason it worked for the guy in that thread is because he had the aluminum Pure Turbo inlet pipe which maybe has a tighter fit that prevented it from popping out with pressure. Since this method doesn't work with the stock/plastic inlet pipe, what would be the correct procedure for testing?


http://www.1addicts.com/forums/showthread.php?t=1143853

[weehe126]

Originally Posted by B Feelgood

Kevin, I am new to the 335/N55 and was simply following the instructions in the thread below. I am assuming that maybe the reason it worked for the guy in that thread is because he had the aluminum Pure Turbo inlet pipe which maybe has a tighter fit that prevented it from popping out with pressure. Since this method doesn't work with the stock/plastic inlet pipe, what would be the correct procedure for testing?


http://www.1addicts.com/forums/showthread.php?t=1143853

Smoke testing.

[B Feelgood]

Originally Posted by weehe126

Smoke testing.

Where do you plug-in or hook up to perform a smoke test on a 55 motor? Also, if there's a leak that only occurs during high boost, how would you go about diagnosing it? Doesn't the smoke test only use a few PSI of pressure just to circulate the smoke?