04 Disco II part search

[jumpcut74]

Just got my 2004 Discovery II SE7 used with 65000 miles and after a week the "Service Engine Soon" comes on. I had the "Mike's 60k Service" performed and all is fine, but the "Service Engine Soon" light came back after a few days. My mechanic buddy who did the 60k service said the pre-air engine blower unit seems faulty because the valve would remain open and the unit probably got fried. He fixed the valve to remain closed and we could hear a fan-like sound when the engine starts. He explained this part/unit is what the engine uses in cold-starting to blow more air into the cylinder to make the mixture leaner.

I am not the most engine-literate so I may have misinterpreted what he said, or the description of the part. Does any of this sound familiar and if so what part does it sound like I need to get (which he recommends I find online vs. having him get it at the local dealer)?

Thanks!

[malmberg]

It sounds like it would be the Secondary Air Injection. It is a black box that is located by the firewall on the passenger side. With a cold start it should stay on for either 30 seconds or a minute. It sounds like a vacuum when you first start her. We will have to see what others have to say. Also if you would get the 4 digit codes that would help everyone on here help diagnose your problem.

[jumpcut74]

Where/how would I get the 4-digit code?

[Disco Mike]

Go to any auto parts store, most will read them for free. Get us the number and what they say it is and then maybe we can help you.