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Hi forum, I'm getting a check engine light and EML light on and off / intermittently. INPA is showing code "5272 downstream supercharger air leak".
Last change was cleaning the supercharger intercooler and replacing the PVC valve. Planning to check the intercooler boots. Would the PCV cause this code?
From searching here it seems this is equivalent to the P1498 code? Is that right?
Quite often a p1498 code is a bad seal from an intercooler boot, or a T-MAP sensor starting to go bad.
First check all the intercooler boots for leaks for sure, this is the most common issue.
PCV should not cause the issue, because yes, the connection is Pre-Supercharger.
Hi I’m following this thread with interest. My 06 s is doing something similar. P1498 reported from blue driver obd scanner. Engine light on for all start ups now and remains on, eml is off on startup but appears after 15/20min driving full revs allowed I’m not in limp mode thankfully.
Looks like I have to do some hunting about the boots etc. See pic for what blue driver reported might help OP or anyone else.
Hi I’m following this thread with interest. My 06 s is doing something similar. P1498 reported from blue driver obd scanner. Engine light on for all start ups now and remains on, eml is off on startup but appears after 15/20min driving full revs allowed I’m not in limp mode thankfully.
Looks like I have to do some hunting about the boots etc. See pic for what blue driver reported might help OP or anyone else.
thank you sir, I will report back if I find it. Hoping its the boots
I had a quick look last night. Nothing obvious standing out. The super charger boot on the right side of the car (left looking from front) has some perishing on the outer lip of the boot as in outside of the clamps. The centre looks good but perhaps the perishing is an indication of it allowing leaks. The other boot under the plastic cover is in better condition. Might just be a replace and hope. checked the air filter and hose again nothing suspicious standing out. Hmmmm
The picture (below) made me realise I may have been looking at the wrong hoses and nipples. Peering from the front hidden under the right car side horn I spied a nipple without a hose. Further back and down I could just about see the hose. As per the blue ring in the pic. Connected it back on and locked it in place with a zip tie (had to remove sc intercooler to make space for hands but not the horn itself).
Cleared code and started her up all good. glad I got there and for the cost of a cable tie I saved $$$ at BMW. Love this helpful forum.
The ol P1498 is a confusing error as it seems to have many options random boots etc. Anyway I’m done for now. Thanks all.
if I'm not mistaken, that would be your fuel pressure regulator hose......if it was off, you should have noticed a drop in fuel mileage and poor running
yes I think your right “vacuum hose to fuel regulator”. I found another post about it (when you know what the issue is it’s very easy to find information ) apparently it can cause fuel mix to lean out at WOT. However I have a bit of a heavy foot and she’s my DD but I don’t drive at WOT for excessive periods and probably not as often due to engine lights on. That being said didn’t notice loss of mileage fill her once approx. every 1-1.5 wks.
All that being said the nipple looked in good order not sure why it disconnected. Last thing I did was change oil and filter no where near the hose. And there’s no retention clip. Is it just supposed to be a barbed nipple and snug hose fitting? Zip tie has taken care of things regardless.
yes I think your right “vacuum hose to fuel regulator”. I found another post about it (when you know what the issue is it’s very easy to find information ) apparently it can cause fuel mix to lean out at WOT. However I have a bit of a heavy foot and she’s my DD but I don’t drive at WOT for excessive periods and probably not as often due to engine lights on. That being said didn’t notice loss of mileage fill her once approx. every 1-1.5 wks.
All that being said the nipple looked in good order not sure why it disconnected. Last thing I did was change oil and filter no where near the hose. And there’s no retention clip. Is it just supposed to be a barbed nipple and snug hose fitting? Zip tie has taken care of things regardless.
Actually, your thinking is reversed....with the hose hooked up correctly to the fuel regulator, at wide open throttle, the fuel mixture will be enriched up, so with the hose off of the regulator, or the intake, the regulator won't have any vacuum being pulled on it so it will be running full fuel pressure all the time.
During normal driving, the more you give the car gas with the pedal, the regulator will be going towards higher fuel pressure at the injectors
Bryan (and yes, I also put small zip ties on all my little vacuum hose connections at the intake and regulator)
Thanks for the info Bryan. To be honest I was only basing the lean fuel from the previously linked thread. This would be a new subject for me and I have no prior knowledge of this system or what it does. So very much appreciate the follow up info.
) apparently it can cause fuel mix to lean out at WOT. However I have a bit of a heavy foot and she’s my DD but I don’t drive at WOT for excessive periods and probably not as often due to engine lights on. That being said didn’t notice loss of mileage fill her once approx. every 1-1.5 wks. 
