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What is the purpose of the air pump on a 1991 mbz420 sel?

Customer Question
What is the purpose...

What is the purpose of the air pump on a 1991 mbz420 sel? Can it be disabled with no negative consequences

Mechanic's Assistant: Have you checked the fluids recently?

Yes

Mechanic's Assistant: What is the model of your '91 Mercedes?

420 SEL, 101,250 miles

Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far?

Mechanic said to replace air pump was +-$850.00 but said it can be "disabled" with no negative consequences.

Submitted: 10 months ago.Category: Mercedes
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Answered in 6 minutes by:
9/30/2017
Mercedes Mechanic: Classic Car Service, Dealership Svc. Mgr. replied 10 months ago
Classic Car Service
Classic Car Service, Dealership Svc. Mgr.
Category: Mercedes
Satisfied Customers: 5,239
Experience: Over 30 years experience in the automotive field
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Hello. Welcome to Just Answer. Please allow me to assist you. The Air Pump is a device that does exactly what its name implies. It 'pumps air' into the exhaust system to reduce emissions. That is the entire idea of having an air pump. Back in the 90's, when stricter emission control became important, reduction in Carbon monoxide, and unburnt hydrocarbons were deemed very important. Since the technology was not what we have today, reducing the exhaust emissions at the tailpipe was popular across almost all of the manufacturers. Yes, the air pump can be "eliminated/disabled/disconnected", etc, but, if you live in an area where emission testing is required on vehicles, be advised that the vehicle may NOT pass an emission test. It is recommended that if you choose to disable the air pump, have a qualified tech who knows what he is doing perform this task. I have done this many, many times over the years. Simply removing the pump is not the answer here, other things need to be done in order to make the engine run properly. Please advise if this answers your questions. Thanks.

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Mercedes Mechanic: Classic Car Service, Dealership Svc. Mgr. replied 10 months ago

If you have any questions, please feel free to reply. Please do confirm you have received my input. Thanks very much.

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