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      08-31-2007, 11:50 AM   #59
Don Juan
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Drives: 2013 535i M Sport
Join Date: Jun 2007
Location: South Florida

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Originally Posted by HyperM3 View Post
ECU only records the unplugged actuator. This is because youre breaking the electrical current to that solenoid telling it that theres a problem with it, ergo storing a code. However, if you just plug up the line with the BB or pellet or whever, it doesnt see it as a break in current, probably doesnt even know if its open or not. Its the vacuum that closes and opens the valve.
I agree with you... unplugging the hose will not give an error because the computer is still sending signals to the actuator to close the valve and when it gets the pressure (hose tied up, golf tee) it sends a message back saying its closed thus no computer logging.
Too mnay factors also contribute to the issues I think people are getting; for instance the weather and in florida we wake up with chilly 79 degree morning nowdays ;-) which does not require your cats to warm up much.

I am certainly NOT going to say that the unplugging of the actuator is harmless, I dunno. But for the life of me I cannot imagine how a little flapper valve is going to either:

A: Get the cats hot faster.
B: Significantly increase back pressure, more importantly I mean how would an increase in back pressure heat a Cat Faster?

Regardless, it's important to note that we are tinkering with OEM stuff and while it seems harmless it could have some unknown effects.
The cats get warmer by increasing the backpressure (less hot exhaust leaving at one time) so the hot exhaust fumes stay a bit longer in the cats warming it up faster. easy analogy...on your barbecue grill, leave the cover close, half close and will see how the fumes escape (faster and slower) and also determines how hot it gets there to cook your food.. :-)
Don Juan 2013 535i M Sport Premium Package, M Sport Package, Napa Leather, Multi Comfort Seats, Aluminum Interior, IND Painted reflectors (front & Back), M Performance Gloss Black Grills , M Carbon Fiber Spoiler, JB4 Stg2 Map 5, K&N filter,20"HRE FF Wheels, 3.75"quad pipes and M5 rear diffuser)
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