and it walks like a duck
Then it probably is a Eucking duck!
sorry - Damn "F" key is broken
Order the part from Mshop.com (don't forget the gasket) swap it out with your existing firstilzenwanger sans gasket. clear the codes and crank her up (126,000 !!!- wadda yah expect a free ride forever?)
If your problem is history - shut her down, pull the OK valve, clean the area and install the new gasket and reinstall the new/rebuilt firsttilzenwanger(German for tuck it to the Yanks fer this piece of itshay German Engineering -no wonder they lost the var-prolly put the same part in their Panzers and Messerjonzes-TG)
Don't forget to clear the codes again and do a check of the short harness for brittleness in outer casing - if nunsuch