Check Engine Light- a bit techy, a bit geeky, a bit preachy.

Posted by on Sep 4, 2010 in David's Blog, Uncategorized | 0 comments

Nobody likes that light. Some people ignore it. I wouldn’t, but that’s because I’m curious. Despite what some people want to think, it’s always on for a reason.

First we plug in the scan tool. We have a scan tool that works with all european cars, and that is what I’m using here. We also have a VW/Audi specific scan tool and a generic japanese/american scan tool.

It takes about 5-10 minutes to load the software and to talk to the computer.

Our codes. These codes are both “wide open” codes, meaning they could have many, many causes. The fact that they are together is a good clue though. Right away, I’m thinking this car has an air leak, which is very common on european cars. Bad German rubber!

I haven’t even popped the hood yet. I want to, but before I do that, I’ll check see how to properly test the engine when these codes are present. We use Alldata and Worldpac Assist as information sources. We also have lots and lots of books and CD info sources on specific European cars.
As I suspected, on this car these codes are often associated with vacuum leaks and MAF sensor problems. I write down the specifications for checking the MAF sensor live data, and head back to the car for a visual inspection of the engine.

I start at the intake manifold and visually inspect the hoses all the way back to the airbox. Whoa, what’s that? Someone has left a giant air hose off.
I guess I should have started with the good old visual check after all.

This is why you don’t let quick lube shops touch your car. They aren’t mechanics, just salespeople.
Well, that was a quick one, and a good starter. Stay tune for check engine light round two…hopefully a tougher one!