I have a 96 GLE automatic with 109,000 miles. I just changed the knock sensor today which involved pulling the upper and lower intake manifolds off. Put everything back together and now the car idles kinda rough, idles low at times, and sometimes stalls when i let off the gas pedal in any gear. Does anyone know what the problem could be?

 

are you getting any Check Engine Lights now that you've done the Knock Sensor Exchange?

 

No, The check engine light did not turn on. I checked all the vacuum lines to and from the intake. Nothing is disconnected. Also while changing the knock sensor I cleaned out the Lower and Upper manifolds. They were really dirty. Could this have caused my problem?

 

It may since you car is re learning fuel maps for the new cleaner breathing. My car made noises when I went from a CAI to a POP charger but it calmed down. give it a few miles to adjust, if it doesn't I would check the dealer for advice.

 

Why did u take the manifold off to change the KS? Isnt it an easy reach from the bottom?

 

Check to make sure your air temp sensor is plugged in or if there is any intake leak.

 

OK I just drove around for a few miles and the check engine light did come on. The codes read MAP sensor and Fuel injection lean (right bank). There was an exhuast recirculation tube on the back of the intake that I reused the same gasket on. I wonder if that gasket is leaking causing my MAP sensor code to trigger?