My 85 failed smog last week and it was due to oil burning that contaminated the catalytic converter along with a bad EGR valve.
The engine is a two year old rebuild I bought from eBay for $1100.00 delivered to the driveway and when one buys a cheap engine, one has to expect it to NOT last long at all and mine didn't. She was down on power, up on fuel and oil consumption and failed smog, what would you do if it was yours?
I'm almost done putting the top end back together after degreasing and thoroughly cleaning the head inside and out, de-carboning the combustion chambers that weren't all that bad and cleaning those valves.
What was the major failure that caused a Gross Polluter rating from the Commiefornia smog test? Cheap, lame, inferior valve guide seals that are made of Buna N rubber, it is not tolerant of petroleum products nor can it handle hot/cold cycles from engine running under normal condition and then cooling overnight. The rubber fails, oil enters the combustion chambers through the guides and doesn't burn, it just messes up the catalytic converter.
The EGR valve being bad didn't help either but, I knew it was bad and then forgot about it because the truck still ran.
The intake valves had the beginnings of a build up of unburned oil and the exhaust valves had a glaze on the faces and more on the seats I removed with a wire wheel and brush.
The passage to the EGR valve in the head was partially clogged so that got special attention and a used but, still good EGR valve was applied because I'm not made of money.
The head is back on the engine and things are coming along nicely all so I can continue to drive my 32 year old Yota.

I have been a motorcycle mechanic for a long time and got into it because automotive repair is too big but, just because I don't enjoy the work doesn't mean I'm not capable of doing a great job. It is no Honda CBX but, it is still Japanese and built with common sense and care unlike our American made counterpart trucks of the same era that were built to fail in less than 100k miles.

 

Made good progress today but, still need to stab the distributor and put the radiator back in then fill and all that good stuff.

 

A problem that has arisen while doing the top end overhaul is a 6mm bolt head that rotted off under the intake manifold. When the head fell off, nothing was holding the bypass plate in place and she just dripped all of my brand new coolant all over the driveway overnight because I didn't notice the leak until the next day. You wanna talk about a drag? I was just about to put the timing light to the now running engine and had to pull the intake manifold off again.

The gasket is NLA from Toyota but is readily available inside full gasket sets so I have to buy a full gasket set to acquire a single $4.00 gasket, don't know where else to get it.

 

I have gasket paper and could have made a gasket the old fashioned way but, I will be doing this again in two years if they continue to make passing the smog test more difficult.
The manifold is back on and I'm sorting through the vacuum lines again but, it got dark.

 

I had to deal with smog test in the 90s when I lived in southern California. I know most dread having to deal with the test and failing them can be a real pain and in some cases get expensive. From my experience and from reading others results,if the motor is in good shape, it is just getting everything functioning correctly. Lack of good maintenace and repair is what I had to deal with. After I got my truck corrected, I passed with flying colors.

Passing smog is something that I have seen several times that the truck runs as good as it has been in a long while. It is just a matter of getting everything back in order. As far as the EGR which can be expensive, I have never had to replace one on the 22 motor. It was just a good cleaning that was needed to get all of the carbon out of it and get it functioning again. Would an EGR that I have cleaned or is worn out pass a California test? I dont know as never had to do it. I think one would.

Once you get the poor quality parts replaced, I think you will do great on the test.

 

After a week of fighting with my truck, she runs again with new valve guide seals and top end associated gaskets are replaced, she is going to pass smog no worries.

 

Congrats - its fun when a plan goes according to plan.

When I lived in West L A I had a station wagon just like the one in your picture.

 

It is a 1970 Chevelle Nomad, basically a super sport wagon.
It left the factory with a 25% underated 300hp 350/4 bolt with a th350 and a 12 bolt rear end that is locked but, now she has a 1970 400 small block bored .30 over and has a nice cam, carb and long pipe headers.

 

Nice, mine was a green 69 with the wood looking stuff on the sides. Had a mostly stock 350 w/at I used it to tow to Riverside Raceway, Willow Springs, etc.

 

I'm going to sell this wagon as soon as the transmission is repaired but, if O was going to keep it I would be buying a complete cowl induction system including a hood and a floor shifter & console, don't like bench seats and never did.

 

The end cost was way more than estimated but, my truck passed smog with flying colors today.
In the end I'm extremely happy she passed even thought I had to dig deep to get it to pass smog legally and was still cheaper by a large margin than buying another rebuilt engine, do the work yourself and save substantial amounts of cash.