I have a 1991 MBZ 300E, living in California; and recently the check engine light is on for a while. Other than that the vehicle is running great.
I ‘ ve checked the computer trouble codes, and it came up with No. 16- that’s EGR (exhaust gas recirculation).
I need help from you guys to find out if,

Do I need to replace the EGR valve or some other part ?
How to Re-set (turn-off) the check engine light;
How to do it by myself (DIY) to replace a new EGR valve.

( I couldn't find an existing EGR valve replacement DIY article on the web site )

what precautions I need when replacing it ?
When I buy the EGR valve from Fastlane- is the gasket included ?

Thank you so much.
Sincerely,
Apmpone
10/03/06

There is a line that runs between the egr and the intake manifold. Replace it and disconnect the battery for about 90 seconds then hook it back up. You should then be good to go. Make sure you have your radio code before disconnecting the battery.

__________________
Jim

I had the same thing on a 1995 E320 coupe today. On that vehicle you disconnect the line from the egr valve to the manifold and then open the throttle all the way and clean the end of the tube where it enters the manifold, that's where the carbon is deposited which cause the code. Then blow it out with compressed air from the other end.

You need to make a tool to get into the tube not sure if it's the same on an M103 engine.

With the engine warmed-up at idle apply vaccum to the nipple on the EGR,
The idle should become rough until the vacuum is removed. If this goes as described the valve and plumbing are good.
The ECU tests the EGR when the engine is warm and decelerating by applying vacuum to the valve, at the same time it monitors intake manifold vacuum and looks for a change while the valve is open,It does this through the manifold pressure sensor in the ignition control unit.
Replace the rubber vacuum hoses to the ignition control!
Mike