We were leaving for a trip from Dayton, OH to Indiana University when the CEL came on. I turned around and read the code. It was 23 blips: Intake manifold pressure (in base module pressure sensor-) with engine running too
high/low.

I took the Montero instead of the Benz and it was like riding in a stagecoach for 3 hours. So now I am in a hotel room wondering just what that message means. Probably a vacuum leak?

The car has new plugs and connectors, the wiring harness and head gasket have been replaced. The egr tube has been cleaned out. It has been running well with the exception of an occasional thrum at idle. (idles at 500rpm which seems a little low) Gas mileage just went down about 2 mpg to 22mpg but I attributed that to the midwest winter blend gas.

Is there a common place to start in disgnosing & curing the code 23? Maybe a common component failure?

Thanks to all!

__________________
Tim Benner

00 ML320 170K
95 E320 wgn 160K