Toyota Repair: CE2000: EGR Valve, toyota camry, car mechanic

Question
Hi Andrew, I have a 2000 Toyota Camry CE. The engine check light has come
on and on checking the code it showing code P0401 which corresponds to
Insufficient EGR flow. My car mechanic (not a Toyota dealer but a small town
experienced person in the age range of 70+) has suggested me that I
should first go for the Engine tune up and then change of spark plug.
According to him the problem might be due to Engine tune up and not
actually with the EGR valve. I bought my car in April 2008 and the previous
owner didn't had it tuned up since 2006. Please advice as to what shall I do?
The mechanic says that EGR valve will cost around $200 and he recommends
that the proper tune up and change of spark plug should take care of the
engine check lights. Please advice me on this as much as you can. I am a total
zero knowledge on car engineering and so is seeking an expert who can help
me understand the problem and its appropriate trouble shooting. I am afraid
to goto the Toyota dealership due to heavy charges they put. I have collected
quotes from many repairers in the town and they all have a swelling bills.
Waiting for your earliest advice and help.

Thanks

Answer
A tune up would be a good idea, but there aren't much procedures that mechanics do to an engine in regard to tune ups anymore. Oil change, plugs, air filter, e-brake adjustment and tire rotation are the main points of a "tune up" at a dealership these days. They don't even include a valve adjustment any longer because most toyota engines are equipped with "shim type" valves. In other words, a shim type engine like your camry will NEVER need a valve adjustment UNLESS the cylinder head is removed and turned upside down allowing all the wafers to fall out.

Anyways, I would allow your mechanic to perform a tune up, then delete the hard code from the ECU. Then drive the car and see if the check engine light returns. If it returns with the same code, EGR replacement is necessary.