Pulled the codes on my 95 Explorer and got code 33. Which the book tells me is "EGR valve fault / not closing properly / TPS fault (Diesel)

I have replaced the EGR valve and sprayed throttle body cleaner into the tubes. The light came back on after the engine was warmed up. After a short trip then restart the light stays off.on short trip back home. I have already unhooked the battery for about a 1/2 hour to reset the computer. What am I Missing??? i have not had a chance to re pull the code but this is the second time I have pulled the EGR valve to check and gotten the code again.

Any help appreciated

Chris
I am going to post this in the Explorer forum also

 

go through the pinpoint test properly. Usually the EGR position sensor (DPFE?) circuit is having the problem rather than the EGR valve itself.

 

What do you mean by pinpoint test and where is the EGR position sensor? Sorry to ask stupid questions just don't have too much experience with this engine.

Chris