my 85 didn't pass smog this year, appreciate any help from those with recommendations to get it to comply

 

not familiar with the communist state of CA's emissions.
so my question is, the ave & max are those specific to your cars year, and engine? or is that what they require for all cars in '23?
I would look at your last smog test and see if or by how much it changed.
I don't know if it would help or not, but maybe put some e85, or rubbing alcohol in the tank for the next trip.

 

Should be based on the year the car was built. Those limits look pretty similar to the limits for the emissions test here in CT for my 1989 back when I had to test (it’s now exempt due to age).

If all of the emissions equipment is in place and working, tune up parts are good (plugs, wires, cap/rotor, etc), timing adjusted to spec and the motor is healthy, no reason it won’t pass.

So, need to start narrowing it down. Make sure it’s in good tune, everything adjusted properly. Does it have a catalytic converter installed (and not hollowed out)?

 

Looks like it needs a new catalytic converter. Either it's gutted, or blown out the tailpipe, or just removed and replaced with a piece of pipe. That's where I'd start.

Your gear ratio in your signature is wrong BTW. There's no such thing as 3.43. There are however, 3.42 and 3.45. Ratios are the ratio (duh) of the tooth counts on the ring and the pinion, which are always whole numbers. (duh... pretty hard to have fractional teeth in a functional gear system) Teeth on the ring in stock-ish ratios are always somewhere hear 40, teeth on the pinion are anywhere from about 8 to about 13. One or both of the tooth counts is usually a prime number: for example 3.73 is 11 and 41, both prime. 3.42 is 12 and 41, and is the usual ratio in that general range in 10-bolts; 3.45 is 11 and 38, and was used in 9-bolts.

 

Thanks guys, man wouldn't if be nice to get California to start letting these be exempt and don't see that happening as they want us all to buy a Tesla

The cat on this thing in 100% original and no one has modified it as I dropped the exhaust and it looked good 2 years ago when I did the fuel pump. A couple of things that I know need attention are the temp gauge is pegged past H and there isn't any melted wire on the sending unit. So I don't know if the gauge is shot or I have a ground short?

Second is the valve stem seals are shot and if you start it again after it sits for about 30 minutes it will drop a cloud and kill any insect in a 50 foot radius. So I'm guessing the plugs are probably fouled?

I bought the plugs, new valve stem seals, valve cover gaskets and the air adapter for the spark plug hole but haven't found the time to change them. I wish I knew a buddy with a lift in the LA/OC area as I'd fund his drinking habit

Thanks for the lesson on rear end gears too @sofakingdom its a GU6 3.42

Open for more suggestions as I'd like to leave the cat being bad as the last option...




Here is last smog too as requested two years/4000 miles earlier

 

The fact that it passed the smog test 2 years ago is promising. Still would be looking at the cat. Might have been fine 2 years ago, but did it disintegrate since then? May be worth disconnecting the intermediate pipe and having a look to see if the honeycomb is still there. Even if the honeycomb is there, it just might be spent and needs replacement.

Valve seals are common, but only cause some blue smoke on startup and shouldn’t affect emissions after it warms up. Also not enough oil to foul the plugs. Still good idea to change them, but probably not your issue.

 

Yeah, but don't turn on the air conditioner in your house. The power grid can't handle it...

 

What kind of valve stem seals did you get?

If they're not the "positive" type, they will be a complete waste of time. They need to look something like these. https://www.autozone.com/external-en...418/134325_0_0 They're available from several vendors including FelPro and Victor-Reinz, and you can get them from just about anywhere. Use them on both intake and exhaust. Don't waste time and money on the O-rings, or on the "shedder" or "umbrella" type. Once the valve guides get a bunch of wear, as always happens over many tens of thousands of miles, they are totally ineffective.

It would be a good time to change out your valve springs as well. It's surprising how much better that can make an engine run, even though it "seems like" the OE ones are "working" "just fine". Any of the entry-level "performance" ones for small block Chevy will be an improvement; Comp 981, the equivalent from Crane or Howards or Lunati or whoever, even the ones marketed as "Z28" springs. Get the matching retainers, keepers, and shims; do away with the "rotators" on the exhausts and the "splash shields; and set them up at as close to 1.700" installed height as possible without going any lower than that. It should be very easy to get them all between 1.700 and 1.720" which is plenty close enough.

As said though, that's probably not the reason for your inspection failure. Definitely should be fixed but probably won't solve that other problem.

 

Those look like the FelPro ones as this is what I bought back in January -

 

Yes indeed: the ones at the bottom of the pic are the type I'm referring to; the ones in the top half are "umbrellas" and O-rings, and therefore useless.

The makers of these things base their int/exh listings on 2 things: (1) what the factory did on certain later engines WHEN THEY WERE NEW, and (2) what works and is effective on LIKE NEW engines. A motor that has valve-guide-seal smoke is NO LONGER a "like new" motor. "Like new" no longer applies. Use "positive" seals on all 16 valves. There's vacuum in the exh ports over various parts of the engine cycle, therefore oil can be drawn into those ports, and cause smoke, like the int valves, once the guides get worn enough.

All that the O-rings do is to keep oil from running down the valve stems off of the top of the retainer. Umbrellas are better at shedding oil off of the stems but do NOTHING about vacuum on the other side of the casting, sucking oil around them and into the guides. That condition doesn't occur in a "like new" motor.

 

Hi "Sofakingdom".

Do the heads have to be machined to install the "Positive" type seals?

 

Not usually but not all heads are the same.

Mic the guides to see.

 

Try Kevin91z on the local so.cal board. He's pretty good at getting these old cars to pass smog. Those numbers are probably not the original pass numbers. Ca lowered the limit by 30% several years back. Just another way to try to get you to scrapped them. Kevin is Dyno Dons kid. His dad would build the engines and Kevin would tune them and still pass smog.

 

Also check that the EGR is working-that can also make a significant difference in the NOX reading.

 

How can I test that the EGR valve is working?

 

Apply vacuum to it while the engine is running. It should lower the idle speed and quality noticeably.

And YES, NOx emissions is what EGR is there for in the first place. If it's not working for whyever, then those are almost certain to be sky-high.

Did a new cat fix the HC and CO issue? Did the better valve guide seals fix the oil burning issue?

 

If I did not already mention, NEW Cats need some miles to break in and run right. I put 2 new Cats on a car with ALL emission equipment present and working, and it barely passed SMOG. I mean by one or three PPM (of what I do not recall).

Tested again, a couple/few years later, it passed very clean, with an INOP AIR Pump!

 

Agree with checking the EGR the way sofa suggests. Also check to make sure all of the vacuum lines associated with the EGR are in place and that the EGR solonoid electrical connector is plugged in.

I suspect though that the EGR is not the issue. EGR only affects NOX. In the test results, both NOX and HC are high. A failed/failing catalytic converter is the most common thing that would affect both readings.

 

Okay thanks for the info on the EGR testing guys, the pumping of air into the system I always read the reason was to get the additional fuel to burn in the exhaust manifold and throws a lot of heat. My air pump has a belt on it and was making a bit of noise from time to time but isn't seized.

It is probably a blown cat as exhaust sounds more throaty and I can smell lots of fumes, I ordered a new cat from Rock Auto, comes next week for $500

The exhaust umbrella ones you pointed out @sofakingdom I have lack the metal banding positive sealing and doesn't look like they they make any brand with that only intake, there is a FelPro high temp one though - https://www.drivparts.com/part-detai...m%20Seal%20Set

 

That is generally correct on the purpose of the air injection system. There is a diverter valve that directs the air to the exhaust manifolds or the catalytic converter. The air only goes to the exhaust manifolds after a cold start while the motor is warming up. The extra oxygen injected into the hot exhaust gasses cause a secondary burn of any unburned fuel within the exhaust manifolds (plenty of excess unburned fuel in the exhaust gasses since the motor is running in a cold start fuel enrichment mode until it gets up to operating temperature). The secondary burn in the exhaust manifolds helps to warm up the oxygen sensor and catalytic converter faster. Once the oxygen sensor is warmed up, it will start working and the ECM will change to closed loop mode (ECM changes air/fuel ratio based on feedback from the oxygen sensor). Once in closed loop mode, the air diverter valve changes to direct the air to the catalytic converter. Those older catalytic converters needed additional air for them to work properly. Newer cats don't need it.

 

The ones you linked to are "umbrella" type.

GARBAGE. USELESS.

Use the part # I gave you on both int & exh.

The difference between "new" and "old" cats needing extra oxygen, isn't the cat. After all, a cat can't somehow miracle up an extra oxygen atom to turn CO into CO2, or to burn leftover soot, or whatever. The oxygen has to come from SOMEWHERE. The difference is the modern CONTROL SYSTEMS aka EFI; which run the engine on the ragged edge of too lean as much of the time as possible, so that there's extra oxygen already in the exhaust stream as much of the time as they can arrange for without causing "too lean" driveability problems. In older cruder more-blunt-instrument Stone Age systems from the dawn of computer control such as the CC QJet or TPI there simply wasn't enough computing power there to manage that. The cat itself isn't really any different. If it was, you could just slap a "new" cat on an "old" car as long as it "fits", and it would work the same. The fact that it doesn't, and that there ARE NO "new" cats that provide that kind of benefit to "old" cars, should be a clue.

 

Totally agree that the chemical reaction is the same (it needs excess O2 to work properly) and the modern catalyst gets the excess O2 from how the engine management system is controlling it (lean burn as often as possible). I didn't mean to imply that you could put a newer 3-way w/o AIR catalyst on one of these cars and get the same or better results as a properly working old style 3-way w/AIR catalyst. Need all components of the "system" for it to work properly, and a modern engine management would be needed as part of that system.

Interestingly, on Walker's website they describe the difference between 3-way catalyst with and without AIR. For the catalyst w/o AIR, they talk about how the engine management system cycles between rich and lean and the catalyst is able to internally store O2 during lean operation when the exhaust has excess O2 and then use that stored O2 during rich operation.

For the OP, I would be putting a new replacement catalyst (3-way w/AIR) and keep the AIR system in place and working.

 

Yep putting on a AIR model from WALKER 81174 as has to be CARB compliant for California.

 

Guess I should have done some more research and stuck my head under the car, I have a early model cat design and this isn't anywhere near that for a F 305-215 (LB9) with those flanges. So the RockAuto one is going back ugh, shipping cost loss on my part. I did some digging too on old posts and saw your recommendation from Summit @sofakingdom for a Magnaflow bolt on and some graduate level fab and welding skills - https://www.thirdgen.org/forums/exha...aders-nos.html

However looks like the only one available that is bolt on from Summit is like $1400 - https://www.summitracing.com/parts/m...maro/year/1985

https://www.magnaflow.com/products/3...verter-3322440

 

PASSED!



Runs smoother and has a bit of a performance uplift, more throaty sound and don't smell fumes like previous so guess it's doing the job.

Thanks for all the help guys!

 

The NO content seems a bit high since 2021 -

15mph

2023 - 748ppm
2021 - 463ppm

25mph

2023 - 729ppm
2021 - 568ppm

Would assume this is EGR performance?

 

Good deal you got it to pass. The original catalytic converter was just spent.

NOX in the 700's is where mine would test, when I had to still test it. Maybe the EGR system isn't working 100%, but I wouldn't worry too much about it. Check to make sure all of the EGR-related vacuum lines are intact, solonoid electrical connector plugged in, but that's as far as I would go for now. If you have another reason to take the upper intake plenum off, then replace the EGR valve at that time. I wouldn't tear it apart now just to change the EGR valve.

 

CA cats are STUUUUUUPID HIGH compared to Federal ones. Not sure what's different about em, butt at some level ya gotta do what ya gotta do. Glad it worked out.

 

My guess is there's nothing different other than a "certification" number that probably cost the manufacturer a big extortion payment to the State of California and passing the cost on to the consumer.

 

I'm just jealous that your max allow NOx is over 1000. For my car's max allowed is something like 735, and that's for a 5.7.

 

My NOx limits were 2320 and 2490. Passed smog the last year it had to at 47 and 72.

 

About 10 or more years, Cali CARB (Ca. Air Resources Board) LOWERED the MAX "allowable" emissions levels, on older cars. (Despite Supreme Court Of The United States (SCOTUS) ruling that Govt. agencies are unconstitutionally acting as unauthorized branches of the legislative system when they implement RULES, not subject to state and federal legislative process). The testing became STRICTER, than when the car were 3 or so years old. The cali Commies, recently sent old car owners a "Survey" asking , Where the cars were stored? How many miles a year are they driven, and WHERE are they driven, etc. ? Ca. has old car owners on their $hit List.

Happy to have left cali for Beautiful S. UTAH!