Disconnect air pump

[Daniel Evans]

I have a 2003 SLS with a bad air pump. after reading much material on the purpose of the pump i have decided not to replace it. does anyone know how to bypass the circuit so the check engine light remains off? I would like to use the check engine light for real problems, not for a smog pump failure.

[Cadillac Jim]

Without fixing the issue, your car won't pass emissions inspection. The car's computers are designed to check for, and report, failures that need the attention of a maintenance technician. Any failures that can affect driveability or safety will turn on one of the warning lights. If emissions are affected, the MIL light will turn on. It's that way because that's the law.

If you pull a fuse or disconnect something, the electrical problem will be detectable by the car's computers. Thus you will get an OBD code. If the failure, e.g. the air pump, affects emissions, the MIL light will come on. So, no, there is no way to disconnect the air pump so that the MIL light doesn't come on.

In years past, I have heard of people that disconnected smog gear in the misguided opinion that this improved performance or gas mileage. Some even remove the catalytic converter. When emissions testing time came around, they hooked everything back up. Sometimes it actually worked; often the crippled car's systems caused damage that prevented it from passing emissions inspection without repairs. For example, disconnecting an air pump on a car designed for one can cause a clogged catalytic converter over time.

[rockfangd]

it would be nice if it was that easy but there is no way around it unless you like more headaches and the check engine light on

[Daniel Evans]

thanks for the feedback. the only purpose of this pump is to flood the engine with fresh air until the engine warms up. once the engine reaches temperature the pump is no longer needed. I have no reason to fix it because i do not have to pass cold start emissions. thanks for the feedback.

[rockfangd]

I realize that. and I sympathize with you. But trust me I have run into enough cars as simple as saturns and there is no way to fool the system.

[Logan]

It's faster and cheaper to replace the pump...rather than try to fool the system.

Anyway...some pointers.

The air pump is mounted inside the drivers side lower front left fender area. Behind all the splash shields.

There is a fuse for the pump. In the underhood fuse block.

There is a relay for pump. See attached pic.

The pumps are known for getting wet...then freezing solid in cold weather...and blowing the fuse. Dont be surprised if yours is dripping wet.

There is a TSB. About updated hoses to cut down on moisture intrusion into the pump.

Also...if the pump tests ok..there are 2 vacuum control valves in the system that can also deteriorate due to moisture...or have actual vacuum diaphram failure.

[winterset]

If the pump is bad, the wheel well plastic just needs to me unscrewed, and tucked back so you have access to the pump. There are no tools needed to remove the pump. Is rests in rubber bushings. I see dorman pumps on sale for $80. The pump is mounted in such a way that when water enters the tubes, it travels down to the air pump, and the motor brushes sit in rust water. At cold startup, the rear o2 sensor looks for an airstream change caused by the air pump supplying the exhaust gases with fresh air/oxygen to lite up the cat. If the rear o2 does not detect this change it turns on the cel. I agree that it's a lot of plumbing for 30 seconds of runtime. But getting the cat hot quicker also extends it's life.

[Daniel Evans]

thanks for the feedback.

[rockfangd]

Here is a good question.

Is there anything that can be done to prevent damage if it is currently working. we have aweful issues here in NY because of the salt and water getting into the pump and valves

[winterset]

Yes. There is a line filter that is sold that dumps the moisture out as it backs it's way down to the pump. I'm not sure how it works and this does not rid the system of existing water.

The other solution I thought of would be to put a tiny 1/16 hole in the center of the bottom rubber diaphragm on the pump. That way when the pump runs, 99% air will pump to the exhaust and 1% would pump air out the bottom and it would rid the pump of moisture. My method will rid existing pumps of water.

[rockfangd]

your idea sounds better than GMs solution. I have tried the filter, filter with hose. ETC... and it seems temporary. I like your idea.