BMW Questions? Ask a BMW Repair Expert for Answers.
The vehicle has to be scanned for codes from the engine. Reduced power usually has to do with the electronic throttle control and it's sensors, but without a code scan all that can be done is a bunch of very expensive guessing. It could be as simple as a wiring repair, or as complex as a module or throttle body replacement. Most good aftermarket shops can scan that vehicle and of course, all dealers can also.
No, an independent shop can probably scan it for you. You cannot install that part. It must be programmed into the vehicle using special tools and will basically render the car inoperable if the part is just swapped in. In fact, many of the parts on that vehicle related to engine control and what not must be programmed in, it is not really a DIY type of vehicle unless you invest a lot of money in tooling.
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