Hello,

I was driving my 2004 Disco in stop-and-go traffic and I noticed the secondary air injection pump turn on. This has never happened before. Normally it turns on upon first start up after sitting over night or after sitting all day during work. It activated and ran for a few seconds then turned off then illuminated the service engine soon light.

Any thoughts on what to look at? I'll be pulling the code this evening which may point me in the right direction.

I don't drive the Disco very often. It sits 5-6 days out of the week without being driven.

Also seems to be running a little rougher than I remember.

Coil packs, plugs, wires and crank position sensor were replaced a year ago with OEM quality parts.

Truck has 132,000 miles.

Any thoughts?