My recurring code 55 has reared it'* ugly head once more, only this time the light has stayed on steady for the entire trip.

EGR has been replaced several times until I found a good one on the shelf at Advance that would pass the bench test. Once replaced, it ran great for a few weeks. Then it started coming back. Cleaned furiously and lubed each time with different oils (turbo oil, lithium grease, 3 in 1, and lastly TriFlow with teflon). It worked well for the past several weeks, but haven't been doing much long haul driving due to some family issues.

Back on the road today and I'll be da@#$% if it didn't come back with a vengence. Stopped at a rest area and cleaned and lubed as best I could with out removing ..... nothing.

Has anyone ever had a digital EGR heat fail? Maybe a flaky PCM driver? Any other thoughts?

I find it hard to believe after several EGR'*, you can't get a good one. The problem lies somewhere else.

Is drivability affected when the light is on?

Believe it or not, I used the 9v bench test that DrJay provided (when I originally had htis problem) and tested several off the shelf at an Advanced Auto. 5 of them failed. They had to get me one from another store and send the rest back to GP Sorenson. The one good one is on the car now and has been working off and on.

Drivabilty doesn't seem to suffer.

I really don't want to believe that it is the EGR failing, but something else. The connector has been replaced and the harness looks good. Not sure where else to go except the PCM. What else will affect the EGR?

I know that the PCM will look for an idle drop when the EGR is activated. Is there soemthign that will interefere with that?