I have done it all, EGR, EGR Mod, VSV, seafoamed, cleaned throttle body, cleaned those damn connection ports on those hose, cleaned out the hoses too... NOW WHAT??!! Fxxxin code still popping!!!!!!!!!!!!!
Sometimes with MOST EFI vehicles the codes are stored indefinitely as long as there is power supplied to the ECM. After one has fixed a sensor related issue, in order to clear the code(s) from the "brain" or ECM, disconnect the battery for at least a good 15 minutes or so. Once you have waited a little while, reconnect the battery and see if you are still getting any codes (or the code).
On my truck the port from the EGR valve that runs along the top of the intake and down into it was totally plugged up. This port is cast into the intake manifold, and is just to the right of the EGR valve as you look into the engine bay facing the truck. If you remove the intake hose and open the throttle, get an inspection mirror to look up into the top of that main "tunnel" to see if the port is clear. That is where mine was plugged. I had the throttle body off and the top of the intake removed when I found the problem.
I took my whole system apart pulled the intake manifold off, replaced all the items you mention plus all the vacuum lines, injectors served, etc etc. While I had it apart I noticed that port was plugged up.
I am sure all the other items helped the truck run better (she purrrrrs) but they would not have kept it from throwing the code again.
have you run the vacuum gauge and other tests in the FSM? Does it pass the tests? are you sure you got the t-body EGR ports and the the intake plenum passages clean? How about the metal passage through the intake plenum from the egr valve vacuum hose to the vsv hose? If it is a 93 or 94 have you checked to see if the steel vacuum lines are blocked? do you have the vacuum hoses hooked up properly to the t-body ports and especially under the intake plenum near the VSV?
If the answer is yes to all those and the suggestions of others and you are sure your new VSV did not get exposed to carbon from old vacuum hoses then all that remains is the egr temp sensor (assuming your truck is not a federal 1993).
It would be good to know the model year. The FSM has a good section on this(i jsut spent time with it today for a customer). You did not mentioned if you checked the EGR it self to see if it actually opens. Also did you check out the temp sensor to see if it functions correctly? The FSM is really great in this area. later robbie
My code cleared after replacing the EGR modulator top from green to blue (or vice verse - which ever is new) and then made sure all tubes and ports were open. I took off hoses/tubes of one by one and bent/twisted to remove dirt or carbon buildup. Been clear for 6-8 months. Nelson
well... the only thing I need to do I guess is the plenum part... have done all the other...well, I guess the last would be the temp sensor... I have a cd rom of the fsm... but doesn't tell me about various issues as some of you have stated...weird... Thanks so much you guys... I'll update after this week & see how it turns out... if any of ya think of somethin' else, by all means... drop it here! Thanks!