Toyota Repair: EGR repair, gasket repair, vacuum modulator

Question
Ted,

I have a 1995 Toyota 4 Runner with 140k miles on it.  I have kept up on the maintenance and the car is in great shape.  Recently the head gasket blew and was repaired and is now, again, running great.  

The other day the engine light came on and I pulled the EFI fuse and reset the computer hoping the light was a by product of the gasket repair.  No luck.  The Code is 71 EGR malfunction.  Can I do this repair my self and what are the steps?  Putting too much money in this older truck may not be a good idea.  Your thoughts are appreciated.

Tom

Answer
Completely testing an egr system requires some special tools and knowledge how to do it.
I can tell you a shortcut which may or may not work, the most common failure of the egr system is the vacuum modulator valve, it's attached to the egr valve with a bracket, this will cost about $80, you can try replacing it and see if the problem is solved.