TOY: Failed Smog

[Michael Young <myoung004@xxxxxxxxxxxxx>]

In case anyone fails smog, always check the simple things first.  A few months
ago, my 1990 Toyota 4x4 truck (22RE) failed the Nox part miserably.  It was
listed as a gross polluter.  Anyway, the Nox was listed somewhere in the 2900
ppm range at 15 mph. The tech said that my EGR was not working.  When I took it
to a "Toyota Specialist," they found out the EGR does work but the passage was
blocked.  After trying to unblock it, they could not do it and recommend that I
get the head removed to fix it.  They did not charge me for over 2 hours of
diagnosis and tear down.  Since the truck has over 260,000 miles, I figured I
might as well get a new head (with slight porting and a slightly hotter cam)
along with the timing chain, water pump and oil pump replaced all at the same
time.  To make a long story short, after all this work, my Nox went up higher to
over 4000 ppm.  The mechanic who I took to (also a smog tech with 12 years
experience) do all the work stated to me from the beginning that he does not
believe the head was clogged and that it probably was something else.  Needless
to say, I was pretty upset at myself for not listening to him.  After about 30
minutes of diagnosis, he said that in his expert opinion, he felt that the new
cat converter was too small and defective.  He also said that the EGR system on
the intake side was probably slightly clogged.  At this point, I told him to
just replace the damn cat converter.  (By the way, I did see him run the tests
and he DID warm up the truck).  After the new converter was put in, about 8 inch
longer than the other one, my truck's NOX DROPPED over 3000 ppm!  He said at
this point, the truck would barely pass and since I was not going to keep the
truck, he said don't fix the EGR system.  The moral to this is look at the
simple things first and speak to someone like a very knowledgeable smog tech
first before committing to spend large amount of money.  Also, just because
something is new (Cat Converter) does not mean it is good.

Mike Young