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Old 12-04-2012, 10:21 AM
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bluebee bluebee is offline
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Location: San Jose, California
Join Date: Mar 2008
Posts: 25,236
Mein Auto: 02 BMW 525i M54 auto 130K
Originally Posted by 1972ford View Post
any thoughts about how else to pinpoint a possible leak?.
I've tried the brake cleaner - but - for a pinhole leak, intermittent leak, or for buried leaks (such as the lower CCV vent hose), it just didn't work for me.
- Does the order of the misfire OBDII DTCs diagnostic trouble codes actually matter (1)

What worked for me to find the cause of my plethora of non-specific lean-misfire codes was a $30 smoke test!
- How to make your own smoke machine (1)

The result was this underside leak, which the brake cleaner didn't get to:

And, this huge leak, which also the brake cleaner (and presumably propane) can't get to:

Moral of the story:
Based on my one experience tracking down lean misfire codes, I recommend a smoke test or simply replacing all the hoses.
- How to diagnose a BMW M54 engine misfire (1) & a cold-engine intermittent misfire (1)
Please read the suggested threads and add value, either by pictures or by descriptions, so the next person stands on your shoulders.
See also: E39 Bestlinks & How to easily find what you need

Last edited by bluebee; 12-04-2012 at 10:23 AM.
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