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Repairing the intake manifold


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Please help me figure out what to do next, thanks!
My 2009 E91 320d has around 120k miles on the N47 engine. I took it in because the check engine light came on, and they said there was a hole in the intake manifold and the linkage and actuator for the swirl flaps had broken.
In addition, this has lead me to suspect that the EGR valve and cooler are probably blocked and will need to be replaced. It would cost more to have a shop repair it with genuine BMW components than the vehicle is worth, so I'll have to come up with a solution on my own or junk it.

I've been thinking about replacing my stock intake manifold with an aftermarket one, and I was wondering whether the Ridex and NTY options I've seen online are good choices, or if there are others.

I have heard that after this is changed, swirl flaps should be removed, but there seems to be contradictory information regarding whether or not this is a good idea. However, I need to check the EGR before making a final decision.
The equipment seems to be fragile, and the mechanical breakdown that has occurred is likely due to the exhaust gas recycling process. I get that it helps with pollutants, but breathing in already burned exhaust gas seems like a waste of energy. Since I plan on purchasing an EGR blanking/removal kit and physically removing the valve and cooler, I believe that I may safely ignore the swirl flaps.

I'm confident in my ability to handle the mechanical side of things on my own (barring any unexpectedly broken nuts, etc.), but the posts I've read indicate that you'll need the software mapping after you're done. I'm not concerned with performance-oriented mapping since this is the family vehicle and I drive it like Aunt Daisy; rather, I simply want to make sure that warning lights and malfunction indicators stop appearing. Is it necessary to do this remapp immediately after the EGR has been blanked?
Should I wait to get the vehicle remapped, or will driving it cause further problems?
Will my automobile still be able to pass the MOT smog test?
Do you have any suggestions for East Grinstead (West Sussex) area mapping software?


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To deflap an N47 engine, just replace the gasket with a 318D model, which does not have the flaps but instead has a blank hole in the manifold. There is no need for a map.
First, make sure the cooler's actuator isn't stuck. Next, check the vac pipe and flush the cooler to make sure it's not clogged.
In addition, I would purchase a secondhand manifold and thoroughly clean it.

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Thanks to everyone who responded, I was able to purchase a genuine manifold from a reputable online auction house. I'm going to clean it well before putting it in.
Still not ready to invest in an egr valve and cooler. When I take the vehicle apart, I'll remove the original and clean it before looking for a replacement, which may be damaged.

Due to work, I won't be able to remove it and replace it until September, which is a bummer since it would mean more than a month without a vehicle, but I'll provide an update then.
Once again, I appreciate it

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Hi, If you want to deFAP your 2009 320d E91, I would advise against removing the swirl flaps. It seems to me that doing so made regeneration of the DPF more challenging, which in turn led to more frequent soot buildup. I've written about the soot accumulation with and without the swirl flaps. After much deliberation, I decided to purchase a replacement manifold on eBay.
With the proper socket, swapping out the intake manifold is a quick and painless process. If there is an air leak at the intercooler connection, the engine will misfire because of a poor air/fuel ratio.
Best of luck!

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That's correct, however the circumstances under which regeneration is possible are what vary depending on whether or not flaps are present. If the engine achieves normal operating temperature while the flaps are in place, regeneration may occur even in city driving. You won't notice a difference with or without the flaps if you do a lot of interstate driving.

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