Fixed my code 332 Check Engine Light! Was not O2 sensor, or any other component! Here is the rundown of how I diganosed it.
1) Warmed engine (ran at 2000 rpm for 2 minutes) and Check Engine light (code 332) came on as expected
2) Connected vacuum gauge bewteen EVR and EGR and reved engine. Gauge showed increased vacuum as RPM increased with warm engine. Hence - EVR and related controls OK.
3) Hooked vacuum pump to EGR and applied vacuum.
Engine began to stall and valve opened & closed. Hence - EGR Valve OK
4) Tested output voltage of DPFE while did #3 above. Votage increased when EGR was open, but not as much as expected. At this point, you could suspect the DPFE but carbon buildup could also cause a restricted flow.
5) Pulled thottle body & checked EGR passage in upper intake. Air could get through, but it WAS restriced and noticable carbon buildup was present
6) Cleand throttle body while it was off and removed all carbon buildup from EGR passage. I ran an old motorcycle brake cable (just the inner cable) through the passage (the end of the cable frays a little, the other end connected to a drill, works like a mini wire brush) and cleaned the passage from the EGR valve to the other end. I used a small hooked tool to reach the opening inside the intake and cleaned all the carbon there as well. I then blew compressed air through the passage and cleaned out all the resulting debris.
7) Put the EGR valve back on, with new gasket, put the throttle body back on and all assocatiaed parts.
8) The battery was disconnected throughout the cleaning process, so the computer was reset & codes cleared. After all was back together it was time for a test drive.
9) Drove 50 miles or so, NO codes! The Check Engine light always came on within a few minutes. I'm sure it's fixed..
Moral: Check the simple things first. Carbon buildup will certainly cause the problem, but it was not easily seen. The process I used was able to pinpoint the problem.
Hope this helps anyone else with this annoying problem.
Email if you need more details. I've been fighting a lower intake leak and this 332 problem for two weeks.
Everything is now fixed, no 332 codes and no leaks.
(lower intake gasket replacement: I can do the entire job in 3 hours now..)