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Discussion Starter · #1 ·
So here is the California smog report for my 1979 Alfa Romeo Spider (~190,000 miles)

Test / RPM
1) 15mph / 2027
2) 25mph / 2308

CO2 / O2
1) 12.39 / 1.01
2) 14.07 / 0.71

HC (ppm)
Max / Ave / Meas
1) 222 / 47 / 87
2) 190 / 37 / 37

CO (%)
Max / Ave / Meas
1) 1.41 / 0.20 / 2.63
2) 1.21 / 0.17 / 0.03

NO (ppm)
Max / Ave / Meas
1) 1396 / 554 / 108
2) 1256 / 468 / 445

I read this high CO at low rpm, with everything else ok, as a rich mixture at low rpms. I yanked the air filter housing out and looked at the fuel injection pump. I notice the way the control rods are set, the unit control lever is far away from the reference screw. Like, I'd say 2mm or so (0.8"). Could that be enough to cause this high CO at low rpms?

A little bit more info. The car has a real hard time starting when cold. Starts stalls. When warm it fires right up. I've always thought the thermal actuator had an issue. But I haven't got around to dealing with it. However, the fuel injection system does not have a temperature setting lever on the barometric compensator (???) , and I'm not sure if that screw needs adjustment or not. Doe anyone no the deal with that on this model?

One last thing. Luckily, my job is overseeing the design and development of smog measurement systems. (Ya so, it's my own fault I failed.)
ANDROS Pneumatics Package by LumaSense Technologies
So I will grab one off the shelf and rig it up.
We don't build full systems, just the part the actually measures the smog.
So it takes a little rigging.
But anyway, I'm going to tinker with the fuel injection and see if I can bring the CO down. I don't have any of the specialty tools so I'll have to wing it. But any advice / ideas I'd appreciate.

P.S. I'm reading through SPICA posts. But I thought I'd post this anyway cause its kind of interesting. I don't see full smog reports up here too often.

2,984 Posts
looking at

CO2 / O2
1) 12.39 / 1.0 there is the prob. set every thing in order in the spica tune up

btw what is idle speed? you will need a new O ring to change it as the old gets hard and will not change. changing the air bypass will affect the mix, faster is not better if it gets too lean. shoot for a CO2 of 14.1 a lot of smogs guys raise the idle to 950 or so thinking it will make HC go down but on a spica it affects the mix. So set the idle speed for best mix.
you might just try changing the idle speed first. as the hi-speed looks good.

put in a fresh 'O' ring and adjust the idle speed up and down and see if you can get the CO2 to 14.1. if not I would do the whole spica set up from step one.
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