Question about 1993 Chevrolet Suburban

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HCL too high, did not pass smog check.

I recently took my car for a smog check but it failed. I put a new Catalytic Converter but I was told that the HCL in ppm was too high and therefore it did not pass, again.

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  • seeib02 Dec 23, 2008

    No scanner nor codes. The tech at the smog check did a pre-test and said that it would not pass the test, he said that the HCL was too high at iddle speed 160 which needs to be below 100. All I saw was that the O2 and CO were below 0.08.

  • kevin carpenter May 11, 2010

    are there any codes in the system ? do you have a scanner handy?

  • Anonymous Mar 15, 2014

    Having problem passing smog, I was told to drive the car to reset the monitors,i have drive for last two weeks with no success. Iwas told to replace the pcm. What should i do,to clear the monitors.i have driven the car for the last two weeks with o success



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Ok well this might be a hard one . from what i can gather by the co reading and the o2 reading is that we are running fat. a couple things can cearte this one how many miles do we have on this mtr, two do we have a vacuumn leak? three is the vech going into closed loop? some how we need to get are hands on a scanner so we can look at a data, other wise you are going to be throwing parts at this vech , and thats not the way to fix your problem. the odds are that you may have some lazy o2 sensors you are close. have you tryed running the vech down the road before you go in for the test. the converter is like a hot water heater you have to bring it to operating temp before it will operate correctly. keep me informed

Posted on Dec 23, 2008


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