[Alifard]

A mechanic connected a scanner to my car today after changing the IAC, he said he saw "Air pump relay" to the off position and didn't know if that's normal on these cars or not, any feedback?

 

[Submariner409]

The Deville, depending on emissions package level, came with 0, 1 or 2 AIR pumps. Look on the passenger side strut tower - there is a bracket bolted to the side. It will have 0, 1 or 2 gray relays with blue connectors depending ...............

When you start the engine on a cool morning, window open, do you hear a very low level vacuum-cleaner-like whine inside the driver's fenderwell ? That pump(s) may run for a short period at cold start in order to send fresh air to the exhaust manifolds (oxygen) in order to quickly light off the cat.

but ........... never heard of a AIR pump disable feature.

The only other "air pump relay" would be for the rear automatic level control compressor.