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Hi all,
I recently purchased a 78 Spider that did not pass smog (California). It looks like the previous owner tried getting it tuned but it still failed. The results were:

My car @15mph: 8.8% CO_2, 5.3% O_2, 246 HC, 4.72% CO, 427 NO.
Max to pass @15mph: 222 HC, 1.41 CO, 1396 NO.
My car @25mph: 9.5% CO_2, 4.7% O_2, 201 HC, 4.02% CO, 413 NO.
Max to pass @25mph: 190 HC, 1.21 CO, 1256 NO.

They recommended that he get a new cat so today I went and got a new cat (the muffler shop said the old cat was empty!) The car also needed a new muffler, so that got replaced as well. However this time, instead of the CO and HC failing, the NO is failing. The results were:

My car @15mph: 11.4% CO_2, 4.9% O_2, 12 HC, 0.00% CO, 2171 NO.
My car @25mph: 10.9% CO_2, 5.7% O_2, 8 HC, 0.00% CO, 1523 NO.

I put my results into a lambda calculator and it said our lambda value is 1.3 (O_O). So my hypothesis is that the previous owner tried leaning out the fuel mixture until it passed without having to buy the cat. Judging by what I've read here on the forum it looks like I should just get a engine and spica tune up to pass smog. So I guess my question is what do you guys think this is the current hypothesis or is there something else I should be looking at?

Thanks in advance for you help!!!
 

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Running rich. Poor combustion usual cause of high CO

Running lean. Advanced timing egr system not working High combustion temperature usual cause of high nox.

Any kind of an ignition miss or vacuum leak can give you unburned fuel and high HC
 

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But Mad North-Northwest
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OX sensor.
This is SPICA, no oxygen sensor.

Yes, you're obviously running WAY lean from those numbers, and I suspect you're right about the PO messing with it. I'm sure some of the SPICA guys around here can tell you how to try to richen it.
 

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I had similar issues until I

A) replaced all the little rubber vacuum hoses.

B) Tuned the ignition and SPICA system really, really well.

C) Put in a fresh tank of gas AND DID NOT ADD MARVEL MYSTERY OIL to the fuel tank. I think the marvel mystery oil makes it impossible for my car to pass emissions. So I leave it out on test day.

If you don't know what I'm talking about, many of us SPICA guys run 4oz per tank of the stuff. It adds the slipperiness that leaded fuel used to supply, and that the SPICA pumps need.
 
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