Wednesday, April 27, 2016

Toyota Smog Test FAIL Again

Well, she failed the smog test again.

This time it was for NOX emissions, and the HC and CO passed.

EGR is a technique used to lower the combustion chamber temperature, thereby reducing the amount of Oxides of Nitrogen produced.

It's a "known issue" with the 5M-GE engine that the passage through the intake manifold from the EGR valve to where it dumps into the throttle body gets plugged up.

A very simple test is to apply vacuum to the port on the EGR valve, which opens it, and dumps large quantities of exhaust gas into the intake manifold.

It should make the engine stumble ot stall, as the EGR is normally disabled at idle.

I hooked the valve to direct manifold vacuum, and I could hear and feel the valve "POP" open and shut.

NO change in idle speed or quality, indicating that the passage is plugged.

Not a terribly difficult job to do, but time consuming, and you have to do with engine COLD.

I'll also be replacing the catalytic converter, as the one on the car looks to be the original one, and after 30+ years, and 165,000 miles, it's about time to retire it!

Since I was driving on expired plates and didn't want to get pulled over and ticketed, I took the side streets to the nearest smog test place. As a result, the car didn't get the usual "30 minute highway blast" to get it FULLY warmed up, and get the converter nice and hot. A converter at the correct operating temperature is essential to get it working correctly, and an old one usually benefits from a good highway run before getting the car tested.

Hopefully a new converter and cleaning the EGR system will get rid of the vicious pass/fail/pass/fail cycle this car has been trapped in for the last 10 years or so.

And I'll also replace the distributor cap and rotor, as the one on the engine looks pretty old, and I have a couple of new ones I bought on sale at Rock Auto.

One other thing I'm considering is to put 5 gallons of lead-free, alcohol free 100 octane VP racing fuel into the tank before I take it back to get retested.

The octane requirement for these engines is only 91 octane, BUT when they were designed and built, the computers were calibrated to use GASOLINE, not some funky blend of gas and moonshine!

As far as I'm concerned, adding 10% booze to the gas I buy at the pump means I'm buying adulterated gasoline. There are a few "pure gas" stations here in SoCal, but none are close to where I live.

Luckily there's a VP distributor here in Long Beach, so getting a 5 gallon bucket is just a short drive.

One of the things about the 10% ethanol blends here in Kommiefornia is that the quality is all over the map. Sometimes the refiners will use a lower grade base stock, and ballast it with ethanol to get the octane up, and sometimes they won't.

And it's well known that 10% ethanol blended gas can damage the fuel systems on cars not modified to use it.

The whole thing is just another "feel good" program to con people into thinking "renewable energy", when we have plenty of oil in the ground here in the USA.

Of, well....enough ranting for now.

Off to the auto parts store (NOT Auto Zone!) to order a converter, and grab a new gas cap while I'm at it. The car passed the "EVAP" portion of the test fine, but the smog guy was suggesting that the old, crusty gas cap get replaced just for peace of mind, and I agree. It's just one of those things I kept forgetting to do.....


  1. Gah, good luck my friend! Chasing those things will drive you up the wall!

  2. Changed the cap and rotor today, dumped in two big bottles of Techroline "Fuel Injector" cleaner, and added 5 gallons of Shell 91 octane.

    I'll clean out the EGR passages tomorrow, and go pick up the new converter I bought.

    I won't install the new converter until I've just about burned out this tank of gas, as I'm having too much fun driving it again after letting it sit almost a year!

    I'm going to do as much as I can to "Kill It With A Brick" before I get it smogged again.

    Hopefully, with everything back to good working condition, it will pass with plenty of margin, and put to rest this pass/fail/pass/fail cycle it's been stuck in!@

  3. Colorado too has emissions testing instead of inspection. I had an '89 Probe that literally smoked while idling. I used to put 2 bottles of HEET in the tank before getting the tests done. Always passed.

  4. Yeah, I've been looking into where they require testing in Colorado, and unfortunately Larimer County requires it.

    Now if I could just talk the wife into moving a bit further out......

    1. Like across the border...into Wyoming.

  5. You may not be happy after replacing the convertor. CA requires you buy one of their "approved" models. There are only two brands selling here. The other brands can't be bothered.
    The smog shop WILL be checking to verify it has the correct issue number laser engraved on the body. Since it must be on the body, it may not have an equivalent to OEM heat shield mounted on it.
    It used to be that they only worried about the tailpipe readings. Now, they demand you use their design, which is predicated on an OEM exhaust system.
    It will probably be noticeably smaller than OEM, if you compare the volume of the matrix. They don't care if the engine chokes at full throttle due to this restriction, they only care about the test speed parameters.
    Hold on to the original unit, and try not to butcher it when it's removed. You may want to replace it afterwards.

    Don't put off doing the test after buying the new one. Get it on and tested ASAP. There have been cases where the state changed the number of the unit, and you are screwed if this happens, since it MUST have the correct number on it. That would be a visual failure, and it won't matter if it also passes the test, since a visual fail is an automatic test fail.

    As you have found out if you did a web check for convertor costs, you will pay 2-3x what the convertor costs in the 49 states, to get that "CA approved" number.

    Verify you have the correct number before beginning work on it. You can look it up on the web. Info from the parts guy may not be up to date.

    Check here:

  6. The one I bought is Kommifornia Kompliant. It has an "EO" number engraved on it.

    There are numerous ones available, but the one from Magnaflow is the only easily available one that's "legal".

    It cost $243, plus tax.

    I'm almost surprised there wasn't an additional "Hazardous Waste Disposal Fee" tacked on to it, like the seem to add to way too many things sold here these days.

  7. Not less moonshine, more moonshine if ya wanna pass. NOX is high combustion chamber temps. For that you need a cool fuel. I've passed some real high mileage , oil burning turds with 2 gals of E-85. The EGR uses exhaust to drop combustion temps to lower NOX. Fix EGR, problem solved or 2 gal corn likker and problem solved without dirty fingernails.

  8. Oh, I'm well aware of what all the various "stuff" is coming out of the tailpipe, and how it gets made inside the engine.

    The EGR system on the car is completely plugged up, and that's what I'm working on today.

    I applied full manifold vacuum to the EGR valve, enough to hear it "POP" open and shut, and there was NO change in idle speed or quality.

    It's well-known fact that these cars clog up the EGR passages between the valve and where it dumps in near the throttle body.

    It's not hard to clean them out, just time consuming, and the engine has to be cold.

    I've had several other people suggest I add a couple of gallons of E85 or denatured alcohol to the tank before I get it checked again.

    Yeah, it's a crutch, but I wanna kill this problem with a brick, so I might just do it.

    Running a smog test is NOT "real world" compared to driving it, and the guys I know who've used 100% gasoline in their daily driving of these old cars say it makes a noticeable difference in how well they run.

    1. Oh I agree with the daily 100% real gas part. I just like to take the path of least resistance to get the GOV outta my life. Emissions testing is obsolete, it needs to go the way of the buggy whip and carburetor. But GOV agencies have no expiration date.
      Didn't mean any disrespect, just advice that has worked for me and many others, one old fart to another....

  9. None taken.

    I agree the C2H5(OH) burns cooler, and might make the difference in getting it passed.

    One "expert" suggested I fill the tank with E85!

    I think he subscribes to the "If some is good, more is better, and too much is just enough" school of thought!

  10. My Turbo Talon hates gasohol. Runs rough, erratic idle, lousy fuel mileage, and no power.
    What works consistently well is Chevron. They don't add any alcohol. Not all of their stations have 3-hose pumps, though. I'm surprised that the state allows this, since you don't get what you are paying for, if the last user pumped low octane gas, and you want hi-test. You're getting a hose full, plus the piping and pump contents.

  11. We have "pure gas" places here, but there aren't any close by.

  12. Why don't you just slip the tech a large bill? That's the way its done in TX.

    1. First you have to find a Tech who's known to do that.


Keep it civil, please....

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