just inspected/passed, now throwing codes at me

[workingonit]

Originally Posted by Effduration

Check the entire CCV system...including drain to oil dipstick tube...

a smoke test looking for a +10% LTFT needs to be a lot of smoke under pressure and you need to smoke from intake boots, brake booster, etc...

Check the rubber caps on your intake..there is one on the CCV valve and 1-2 on the rear of the intake near the firewall. The fact that you have similar LTFT's on banks 1 &2 tells me the vac leak is likely before it gets into the intake...

I haven't yet taken a close look at the plumbing under the beauty cover; out of sight, out of mind. I'll use my cheap Android borescope to take a close-up look under the manifold.

My smoke tester is homemade, very low pressure, and probably not up to the job. I have to either buy a better one, or get better smoke-making fluid.


I'm totally unaware of the vacuum hose routing on the M54...it took me many years to even learn of all the hoses on my older American cars (even though I replaced most all of them, over the years), and I have no idea where BMW has hidden them in their over-engineering way. I'm gathering photos of hose routing from the internet.


I can see how this is going to end...I'll have to try another smoke test, then a carb cleaner spray test, then the borescope examination, then a total removal/replacement of any or all rubber parts (plastic too, since BMW loves plastic, even moreso than General Motors). Been there, done that before, but never on an X5. That's why I keep five cars on hand, just in case.

the vac leak is likely before it gets into the intake
So, it could be from the SAP, CCV, fuel filter/pressure regulator, manifold rear, brake booster, etc., and parts & places unkown. I've got a hand drawing from another E46? website showing more possibilities (I'll find hidden treasures while I'm searching, I'm sure). I was hoping not to take it all apart so soon....