[n55demon]

Ever since I gotten my car, I have gotten the drive train pop up time to time under full throttle. Sometimes when going up a hill under throttle it’ll pop up. Sometimes when I’m just punch it and it’ll pop up. When in higher gear and you press try to build boost it’ll pop up as well. All these are times I’ve noticed it. When I took it to my local bmw indie shop, he said it might be my boost pressure regulator or turbo. Anyone can confirm this? Recently bought a obd2 plug and saw that my boost was under and sometimes a bit over 1 psi. Anyone can help me with this? I saw it hit 3 psi, car def feels slower than usual but maybe it’s all in my head?

[n55david]

Originally Posted by n55demon

Ever since I gotten my car, I have gotten the drive train pop up time to time under full throttle. Sometimes when going up a hill under throttle it’ll pop up. Sometimes when I’m just punch it and it’ll pop up. When in higher gear and you press try to build boost it’ll pop up as well. All these are times I’ve noticed it. When I took it to my local bmw indie shop, he said it might be my boost pressure regulator or turbo. Anyone can confirm this? Recently bought a obd2 plug and saw that my boost was under and sometimes a bit over 1 psi. Anyone can help me with this? I saw it hit 3 psi, car def feels slower than usual but maybe it’s all in my head?

It might be a lot of things.. we can't even begin to guess without proper diagnosing.. codes?

[mike@x-ph.com]

Originally Posted by n55david

It might be a lot of things.. we can't even begin to guess without proper diagnosing.. codes?

+1

[thejeremyman9]

https://f30.bimmerpost.com/forums/sh....php?t=1732327

[n55demon]

Originally Posted by n55david

It might be a lot of things.. we can't even begin to guess without proper diagnosing.. codes?

finally made an appointment with one of my good friends shops and went in there today. it had a bunch of codes come up. car is def in limp mode. 1, my water pump went out and 2. car isnt building any boost and feels dead. they did a smoke test on it and it was leaking from the charge pipe near the turbo. hes gonna check the turbo when hes doing a water pump and going to get a new charge pipe seal to see if it builds boost again. if not may have to get a new turbo.

[n55david]

Originally Posted by n55demon

finally made an appointment with one of my good friends shops and went in there today. it had a bunch of codes come up. car is def in limp mode. 1, my water pump went out and 2. car isnt building any boost and feels dead. they did a smoke test on it and it was leaking from the charge pipe near the turbo. hes gonna check the turbo when hes doing a water pump and going to get a new charge pipe seal to see if it builds boost again. if not may have to get a new turbo.

It's prolly just the charge pipe man. But yeah, do the waterpump and thermostat

[n55demon]

Originally Posted by n55david

It's prolly just the charge pipe man. But yeah, do the waterpump and thermostat

yep, have a feeling its the charge pipe as well. doing the water pump and thermo for sure.

[mike@x-ph.com]

Originally Posted by n55demon

yep, have a feeling its the charge pipe as well. doing the water pump and thermo for sure.

let us know if that fixes the issue

[Rebound]

Originally Posted by n55demon

finally made an appointment with one of my good friends shops and went in there today. it had a bunch of codes come up. car is def in limp mode. 1, my water pump went out and 2. car isnt building any boost and feels dead. they did a smoke test on it and it was leaking from the charge pipe near the turbo. hes gonna check the turbo when hes doing a water pump and going to get a new charge pipe seal to see if it builds boost again. if not may have to get a new turbo.

Charge pipe failure is very common, but turbocharger failure is not common.

If you're replacing the water pump, it's best to do a more thorough job. The parts cost more but if you're paying a shop the labor will be less if they do it all at once.

I replaced the water pump, thermostat, something called the "Mickey Mouse Flange," and the coolant expansion tank return hose (a very thing hose which goes across top front of car).

I also replaced the entire drive belt -- the drive belt, tensioner, and pulley.

Fix it now or fix it on the side of the road. Not saying it's urgent, but sounds like you're close to the age where those items fail, and you should replace them as your budget permits.

[n55demon]

Originally Posted by mike@x-ph.com

let us know if that fixes the issue

will do sir!

[n55demon]

Originally Posted by Rebound

Charge pipe failure is very common, but turbocharger failure is not common.

If you're replacing the water pump, it's best to do a more thorough job. The parts cost more but if you're paying a shop the labor will be less if they do it all at once.

I replaced the water pump, thermostat, something called the "Mickey Mouse Flange," and the coolant expansion tank return hose (a very thing hose which goes across top front of car).

I also replaced the entire drive belt -- the drive belt, tensioner, and pulley.

Fix it now or fix it on the side of the road. Not saying it's urgent, but sounds like you're close to the age where those items fail, and you should replace them as your budget permits.

yessir, getting it fixed now! cars in my friends shop right now. Its in limp mode, so it feels like shit and fans are 100% duty all the time. We are gonna try to get a new seal for the charge pipe, if it fixes the boost issue then great. i still havent decided if i want to keep the car for x period of time, want to trade it in for an m2 or something in a little bit. if so then i plan on keeping it 100% stock to trade up and not dump money into it.

[n55demon]

Originally Posted by mike@x-ph.com

let us know if that fixes the issue

so i got a call from them today. waterpump and thermo changed. the charge pipes were fine no cracks in them and they changed out all the seals so its not leaking anymore. but the car is still throwing a code that boost isnt holding/building. under hard throttle the drive train light still comes on. do you have any guesses? im guessing it may be something from the turbo back?

[n55david]

Originally Posted by n55demon

so i got a call from them today. waterpump and thermo changed. the charge pipes were fine no cracks in them and they changed out all the seals so its not leaking anymore. but the car is still throwing a code that boost isnt holding/building. under hard throttle the drive train light still comes on. do you have any guesses? im guessing it may be something from the turbo back?

We can't guess without logs and codes.

[n55demon]

Originally Posted by n55david

We can't guess without logs and codes.

should i buy an obd2 reader and get the info this way? im gonna go to the shop in a little and ask if they can give me the code. i had my other mechanic who works on bmws and knows the 335i platform well, he said i might needa new boost pressure solenoid. so im gonna do that first before anything and pray it fixes it.

[thejeremyman9]

Originally Posted by n55demon

should i buy an obd2 reader and get the info this way? im gonna go to the shop in a little and ask if they can give me the code. i had my other mechanic who works on bmws and knows the 335i platform well, he said i might needa new boost pressure solenoid. so im gonna do that first before anything and pray it fixes it.

Throw parts at it and pray? Sounds like an expensive approach. Before replacing any parts you should have datalogged and scaned for codes, including shadow codes.

[n55demon]

Originally Posted by thejeremyman9

Throw parts at it and pray? Sounds like an expensive approach. Before replacing any parts you should have datalogged and scaned for codes, including shadow codes.

We are gonna test the boost pressure regulator next week, the only code the car is throwing is just the one dealing with boost. I don’t know the exact code, forgot to ask them. But to me it seems like it might be the boost pressure solenoid. Charge pipes were fine, and we fixed all the boost leaks. Aside from the solenoid, I think it would either be a bad cat, seiezed turbo, or maybe my engine compression is just down to shit. But car has 80k miles on it. I know the boost solenoid was a common issue with the n54s and seems to be common on 55s also. Considering my waterpump went, I would assume that my boost solenoid also went bad. Just my train of thought and the googling. Also what I’ve talked to with the dude who works on my car. Let me know if it makes sense or I’m missing something. My old mechanic also told me that i should replace the boost pressure solenoid as well.

[thejeremyman9]

I dont think its that common on N55 but i suppose if you are already going down that path replace it and report back.

[harkes]

I have had no boost pressure solenoid failure on my 2012 but I have had two pcs starting to make a loud humming sound. Just replaced at that point.

[n55demon]

Originally Posted by harkes

I have had no boost pressure solenoid failure on my 2012 but I have had two pcs starting to make a loud humming sound. Just replaced at that point.

pcs?

[n55demon]

Originally Posted by mike@x-ph.com

let us know if that fixes the issue

so i just put in a new boost solenoid and it seems fixed the issue i believe. no more light on full throttle while 2k rpm in 4th as it usually did. also i can hear the despool when i rev it in neutral. car def pull a lot harder, especially in first and second, pull the head back to the seat.

[n55demon]

Originally Posted by thejeremyman9

I dont think its that common on N55 but i suppose if you are already going down that path replace it and report back.

seems to have fixed the issue with a new boost solenoid!

[mike@x-ph.com]

Originally Posted by n55demon

so i just put in a new boost solenoid and it seems fixed the issue i believe. no more light on full throttle while 2k rpm in 4th as it usually did. also i can hear the despool when i rev it in neutral. car def pull a lot harder, especially in first and second, pull the head back to the seat.