Here's one for the pros. I have an insufficient flow code on my 97 Sebring 2.5. Replaced egr and transducer/solenoid and the light came back on. Went to Alldata and did all the diagnostics except for the pcm because they don't cover it for some reason. Test results indicate a bad egr. Pulled it,tested it-it's ok. I've got correct vacuum readings to and from the transducer. The exhaust tube is wide open. The passage through the intake is open. With the solenoid unplugged I have vac to the egr diaphragm and as soon as I plug the solenoid in the vac stops as it should, indicating a signal from the pcm. Before I take this to a shop and spend $$$ for a diagnosis I'd like to know what components on this car control the pcm signal to the egr solenoid besides the map sensor. And if they are not working properly wouldn't they set their own codes? Any help would be appreciated.
Thanks

 

Maybe this will help?... http://www.obd-codes.com/p0401

 

Thanks Swanny but I've been there and it only covers the fixes I've tried. It is a great site just a bit too generic for my problem.