CA Smog Prep - What Do You Do?

[Targa Me]

Hello Everyone.
Well my turn is coming up soon... the dreaded smog check.

My Carrera (84) has a stock 3.2 with almost 220k miles on the clock. The car runs fine but I don't know for certain if it'll pass the smog check.
I will do the usual to prepare; replace cap, rotor, plugs, clean air filter.

Do you do anything special to prep your high mileage car for a smog check?
I've heard that changing the oil and oil filter and making sure tire pressure is at proper psi is also recommended. (Improper tire pressure places an additional load on the engine.)

I've seen products like Sea Foam and BlueSky 3 in 1 Fuel Conditioner that claim to help in passing a smog check. Have you tried any of these products?

What are your suggestions?

Thanks.

[zippy_gg]

Be sure to give it an Italian tune up the night before, and show up with an engine fully warmed up on the day of the test.

[tobluforu]

Run some techron through it, change oil after, tune it up, over inflate rear tires, run the piss out of it before the test, do not shut it off when waiting; test in first and second. If it does not pass, I have used that bluesky stuff on another car and it worked wonders. Others with your motor will have a better idea.

[Eagledriver]

If your engine is running well, there is no reason it should fail. I use a "test only" station. These stations have a vested interest in having you pass. They can't sell you a new gas cap or any other repairs, and they have one free retest if you fail (at least the one I go to has). As others have said the main thing is to have a good warm up to make sure the cat is up to temp.

-Andy

[hcoles]

pump up rear tires - less drag on roller
Italian tune up as mentioned, and keep hot before test
borrow a known good cat
new plugs wouldn't hurt
check for air leaks

[skunked]

like others have said, make sure the cat is hot.

My 78 just passed on the rollers with 214K on the clock.

[Joe Bob]

Pretest.....then get it hot.....

[hcoles]

my understanding is that stations are not supposed to give a "pretest" without recording the results with Sac, they can allow a free retest after you fail

[Joe Bob]

Yes, that is correct...shoulda mentioned that you go to an indy that has a tester and no license......

[G50]

You can get it pretested to see where you are at, just go to an independent mechanic with a freestanding gas analyzer, instead of a "just smog" shop.

But you shouldn't have any problem if the car is running well. A stock Carrera should pass Cal smog with flying colors, as long as the equipment is all there. I just had a smog on my '88, which is all stock, and all of the numbers were a fraction of the standard allowed, with some numbers at zero.

IMO the biggest question mark (probably the only question mark if the car has just been serviced with new plugs, filters, etc) on a high mileage is the cat converter. With a fully functioning cat converter, you should have no problem, but they do lose their efficiency with miles, and 200+ is quite a few miles on a cat.

For the cat, the above advice is good. The hotter you can get it, the better it will work.

[ShinySideDown]

Not that I've ever done it , but I've heard a gallon of denatured alcohol in your gas will help.

Do it with a quarter tank or less and then drive and fill up ASAP afterwards to use up/dilute it out. You don't want to leave that much alcohol in the rubber lines for long.

Don't use rubbing alcohol from the drugstore. It's usually full of water.

[juanbenae]

use low octane gas as well. it burns more complete like than the higher octane fuels.

[DRACO A5OG]

Hey Larry,

Tire Pressue? never heard that but makes perfect sense. Get her really hot for sure.

As far as additives, you need to burn thru them plus a full tank to get it all out. If you have to use an additive try the BG-44K, poop is amazingly strong and she will feel great

Reconnect the brown wire and re-install the OEM cat, if you have it. This is my routine every two years. I will add tire pressure too, hell I wonder if 42 pounds in the rears will be better???

+1 test first after preping her.

Jim

[nkotselas]

I will be in the same boat soon, I have a 84 euro engine with a SW chip. Is it recommended to swap back to my original chip?

[rusnak]

I bring a new gas cap, re-connect the brown "bridge to ground" wire to the dme, check air fuel ratio, adjust valves, new cap and rotor, and install the new cat. Passes no problem.

[Peter Zimmermann]

Be sure to add Pro Gard (Techron) a couple weeks ahead, drive the car to full temp before arriving at the Test Only station, always make an appointment in advance, use only Chevron Premium, give tech the keys, cross fingers and go for a walk. I have no problem shutting my car off while waiting to put the car on the rollers, but it is an SC and has never affected the readings yet (letting it idle and get too hot can work against you).

With a Carrera, a pre-test, if you can arrange one, is a good idea. The AFM can go rich in those models, and if that happens the car won't have any real symptoms, but will fail the bi-annual test.

[Quicksilver]

Originally Posted by rusnak

I bring a new gas cap, re-connect the brown "bridge to ground" wire to the dme, check air fuel ratio, adjust valves, new cap and rotor, and install the new cat. Passes no problem.

+1 on the brown "California" wire. That will help with the NOX which is where the Carreras can have an issue.

[Quicksilver]

Originally Posted by car 311

use low octane gas as well. it burns more complete like than the higher octane fuels.

The difference between low octane and high octane is simply that high octane can take more pressure and/or heat before self igniting. They both have the same quantity of BTUs per gallon and unless the manufacturer has upgraded the additive package then they are otherwise identical.

The only way you will see a detectable change is if the engine has a knock sensor so it can add additional ignition advance to take advantage of the higher octane's increased resistance to self igniting.
The 80's Carreras don't have a knock sensor so there will be no difference unless you managed to find low enough octane to make it detonate during the test. The pressure spikes would then cause more NOx output which has been the problem that the 80s Carreras have been trying to avoid to begin with.

[Targa Me]

My Carrera is not an original CA car. Does that mean I don't have the "Bridge to Ground" wire?

[DRACO A5OG]

Check under the seat, it may juts be disconnected, BROWN WIRE and White Box Connector, It may be covered by tape.