Rough idle. I would like to replace the EGR valve myself. searching the Web- I can find nothing, let alone a shop manual on this truck. Any help appreciated a great deal. A MONTH LATER UPDATE JAN 2004. - I cleaned the EGR Tube. It took me maybe 20 minutes tops to take it off. And I added a bottle of Gumout Emission cleaner to the gas. The check engine light went off and it idles fine. Now I add Mystery Oil to every tank and keep my fingers crossed.

__________________
Steve Danville
what i did myself.
CPS
rear shocks
MAS x 3.
SparkPlugs (twice)
Fuel pump & Filter
Window switch
replaced both failed horns with Honda horns.
Cleaned ERG Tube
Oil changes
Oil consumption Fix
Brake Pads
A/C Recharge
Anti-Freeze change X 2.
Front Shocks. Monroe. $90
Mercedes Warrenty Work:
Harmonic balancer,power steering clamp. Cat converters.Drive Shaft Bearing.s
Replaced Outer Lower Tie Rods and front lower ball joints at 156,000 miles

Easy job! However P0 400 doesn't mean that the valve is bad.
Most of the time you will find the EGR valve pipe clogged-up.

The valve is behind the RIGHT cylinder head.

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
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190E 2.3 16V ITS SCCA race car (sold)
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Retired Moderator

well thank you very much for the reply.
I will attempt to locate it---then remove the pipe and clean it before I buy a new valve.

Any tips on doing this? I was only able to reach back and take the 3" rubber hose off the EGR. Could not even see a metal tube.

12/24/03 update ..I located the EGR Tube with a mirror and lighting. Removed the big plastic intake tube to make room. removed & cleaned out the EGR tube and idle 80% improved. Your help was extremely vauable.

steve

__________________
Steve Danville
what i did myself.
CPS
rear shocks
MAS x 3.
SparkPlugs (twice)
Fuel pump & Filter
Window switch
replaced both failed horns with Honda horns.
Cleaned ERG Tube
Oil changes
Oil consumption Fix
Brake Pads
A/C Recharge
Anti-Freeze change X 2.
Front Shocks. Monroe. $90
Mercedes Warrenty Work:
Harmonic balancer,power steering clamp. Cat converters.Drive Shaft Bearing.s
Replaced Outer Lower Tie Rods and front lower ball joints at 156,000 miles