SMOG check failed need help (1 Viewer)

[LEO5651]

Today my friend told me that his 1981 Toyota FJ40 had failed the local smog test. He as had the truck since new and it never failed before, and this is his daily driver so any help in helping pass this test with possible solutions will be a big help as he has only 30 days to pass or face problems with the local DEQ.
As he told he had the trucks engine as hot as possible while testing, he took it to the required RPM and failed at the HC area of the test, the guy at the station did one more test and it too failed again. I have included his results from the test that may help anyone that knows what all this means. He said he was told that the CAT was the problem but we checked it with a digital heat gun with the laser at the front of the pipe just before the cat and the same at the pipe exiting the cat and had a reading low at the front and 20 or so degrees hotter at the exit telling us that the cat was working ok, correct us if wrong. He also did a rattle check of the CAT with no sound of broken parts inside. We checked the CAT sensor and it was hard to get a resistance check (mostly a ground issue) but we can up with a resistance of 203 and I believe the norm is 3-200 for resistance.
Other than that I have no clue what to check next.
Being this is his daily drive he is pretty worried about being without a car so please any guidance is most welcome.
Photo 1 is the 1st test, and photo 2 the 2nd test.

Big thank up front

 

[Bear]

Mmmmmmmm--spaghetti !

Thank-you California smog-Nazis.

 

[Fj moneypit]

What causes high HC? Common High Hydrocarbon Faults.

m.smogtips.com

 

[Downey]

Back in the day we would install a fresh cat. converter (even if the rig did not require a cat.) and pass the smog test every time. Problem is all the other smog parts under the hood start failing after about 8-10 years old, and you chase defective pieces FOREVER at $$$$$.

 

[LEO5651]

His truck has never had any real replacements as in smog pump, or any other related equipment, it is pretty much all stock even the carb still has the drill out cover over the mixture needle. 38 years, I did a valve adjustment to it last year and rebuilt the PS pump other than that it could anything after that much time. Yeah the engine bay is a rats nest of hose. Sent him a copy of what FJ moneypit posted - place to start.

 

[Dynosoar]

Good O2 numbers, air injection looks good. CAT is probably dead. Look at the plugs. Is it running rich?

 

[LEO5651]

We just finished about two hours of fiddling around with a few things - here is what we did.

Found that he did not tighten down (barely snug) all his spark plugs from when he replaced them a year ago
cleaned an gapped and replaced -tight. Plugs had white from the fuel and some black shoot but not wet or with lots of build up on them. Not to bad.
Air filter needs to be replaced but usable
Checked the smog pump and is working fine
Removed the dizy cap and inspected for dampness or faults-ok
Checked PVC - good
Timing - dead on

I decided to ask him if he would mind if I drilled the cap off of the mixture screw that has been on since new, okayed
Took the cap off and removed the mixture screw cleaned with 000 steel wool (tarnished bad) reinstalled lightly seated backed out 2 1/2 turns and fire it up. Ran bad then with a bit of adjustment now it is so much, much smoother than before nice and steady no lobbing.
So that was well worth the effort - 38 years without adjustment - wow.

The rich smell seems to of lessened by 3/4 to my nose test but has some high temp at 2,700 rpm flowing from the exhaust. Pretty hot so I wonder if the cat is restricted ?
That's what we got done today. I asked him to drive it for the day and on Friday we can take another look and see if the mixture needs some adjustment.
I am pretty much out of checks to do without special equipment.

Thanks guys

 

[emac]

No clue if these are any good or if they will actually fit, but for $135 it might be worth a try.

1981 Toyota Land Cruiser Catalytic Converters & Parts — CARiD.com

Whether you are seeking a replacement or performance catalytic converter for your 1981 Toyota Land Cruiser, CARiD is your headquarters for premium parts.

www.carid.com

 

[LEO5651]

I will pass this on to him-thanks

 

[fjc-man]

Is the EGR circuit working as it should?

 

[Brian/99uzj100]

OP
I have a 76 FJ40 and have had to get it smogged every two years for the past seventeen in CA.
Any time the HC has failed to pass at idle, but all the other numbers are fine I've had a big vacuum leak.
The leaks on my rig have either been around the intake/exhaust manifold gasket or around the base of the carb.

 

[LEO5651]

UPDATE:
He took it in today and Failed again but with much lower numbers on the HC, lots lower.
I think removing the factory cap that was over the mixture screw and being able to adjust was a big help along with the seating of the spark plugs. 116 from passing. He is now looking for a CAT as he thinks after 38 years it maybe due anyway.
I readjusted the mixture for drop lean so it as good as it going to get. took 3/4 in to lean from were it was not sure if that would get him to pass with that adjustment.
What do you guys think?
Thanks

 

[LEO5651]

Sorry forgot to ask anyone have a lead on were to find a new CAT sensor for this FJ40 year. Seems as the cats can be found but the sensors are a different story.
Thanks

 

[emac]

Making progress, as Brian said in post 11, check for any vacuum leaks. It would be nice if you had a way to measure HC while you played with mixture and checked things.

 

[Spike Strip]

1st, is the truck in Calif ?

CAT sensor is NLA so you'll have to find a used one. Get the Magnaflow CAT for CA/NY or 48 State. It's the same setup as FJ60s.

FWIW, that sensor measures CAT temp is is used to direct the Air Injection to either back thru carb or into engine or down tailpipe to cool excessive temps.

http://www.trollholescruisers.com/Tech/Manuals/Engine/1981%202f%20Emissions%20Control%20FSM%20.pdf

 

[Otis]

If in CA, make sure that you get an "approved" aftermarket catalytic converter (Aftermarket Catalytic Converter Database). During my last smog check the tech was insistent on making sure the number stamped on the cat corresponded with the approved cat numbers. Apparently, they are supposed to check...

 

[Spike Strip]

Yes, CA techs will check to see if you have a CARB compliant CAT and fail you if u don't.

 

[ToyotaMatt]

Today my friend told me that his 1981 Toyota FJ40 had failed the local smog test. He as had the truck since new and it never failed before, and this is his daily driver so any help in helping pass this test with possible solutions will be a big help as he has only 30 days to pass or face problems with the local DEQ.
As he told he had the trucks engine as hot as possible while testing, he took it to the required RPM and failed at the HC area of the test, the guy at the station did one more test and it too failed again. I have included his results from the test that may help anyone that knows what all this means. He said he was told that the CAT was the problem but we checked it with a digital heat gun with the laser at the front of the pipe just before the cat and the same at the pipe exiting the cat and had a reading low at the front and 20 or so degrees hotter at the exit telling us that the cat was working ok, correct us if wrong. He also did a rattle check of the CAT with no sound of broken parts inside. We checked the CAT sensor and it was hard to get a resistance check (mostly a ground issue) but we can up with a resistance of 203 and I believe the norm is 3-200 for resistance.
Other than that I have no clue what to check next.
Being this is his daily drive he is pretty worried about being without a car so please any guidance is most welcome.
Photo 1 is the 1st test, and photo 2 the 2nd test.

Big thank up front

View attachment 2096727

View attachment 2096728

View attachment 2096729

whats up Leo , Matt here

im Very Curious if u have had one of these on Hand during this entire process you and your Friend are

undertaking ?

Please Let me know when u see My post here , I don't wan't to assume either way if u follow me


But if you Don't , I can help better explain why you DO need one Right Away without delay ,

and Before u and your friend sped another Dime on any Parts what so ever , even a Zip Tie ............


you can also PM me , so feel free .............

 

[ToyotaMatt]

 

[LEO5651]

Not in CA so he is good, we do have both a 1979 and 1981 USA Emissions book on hand so big thanks for the uploading someone can use that for sure.
Did as best as possible vacuum check without finding any problems in that area, seems pretty well sealed. Checked the carb base and is sealed very well. Break booster line and anywhere else.
He does have a small what maybe a intake manifold/exhaust manifold gasket leak from the under side, a puttering sound, but I think it is coming out of the heat control valve side shaft, pretty common on most 2F. Used a section of garden hose to ID that.
I hope that there are no cracks in the manifolds or the horrible crack at happens just below the carb on the inside intake manifold causing raw fuel issues.
The senor that in in the cat now may not be usable due to rust around the were it screws in, we will check that a little closer.
With the numbers coming down as far as they did and only 116 points to go to pass I was thinking of going with him and before the test, setting the mixture as low as possible (light stumble) to see if it will make it to pass and give him some more time to correct this issue. without fear of loosing he daily driver. $11 crap shoot.
Thanks