Re: failed smog :-( (Fwd)

["charles.slayman" <Charles.Slayman@domain.elided>]

Jeff,
	Here are the smog numbers I've seen on my '89 Spider under various conditions
(max is California standard, typ is typical obseration for cars registered in
CA, act(vac leak) is the actual on my Spider with a know vacuum leak, act
(burned valve) is the actual with a known burned exhaust valve and act (174K
mi) is the actual after 175Kmiles with the engine in good running order -
rings, cat con and O2 sensor are original, only valves are new):

				IDLE/2500 rpm
HC(ppm) max			120/140
	typ			29/20
	act (vac leak)		196/109
	act (burned valve)	380/222
	act (174K mi)		30/29

CO(%) 	max			1%/1%
	typ			0.1%/0.1%
	act (vac leak)		0.01%/0.02%
	act (burned valve)	6.44%/6.03%
	act (174K mi)		0.11%/0.27%
	
CO2(%) 	max			na
	typ			na
	act (vac leak)		7.7%/12.4%
	act (burned valve)	9.3%/9.9%
	act (174K mi)		13.7%/13.7%
	
O2(%) 	max			na
	typ			na
	act (vac leak)		9.4%/3.3%
	act (burned valve)	2.4%/1.9%
	act (174K mi)		2.4%/2.1%

	Looking at your results, your CO numbers look OK.  And your HC numbers aren't
too bad at 2500rpm.  So the problem might be a low speed miss.  If your cat
con was gone, I don't think you'd see better results at higher rpm, so let's
rule that out.
	So here are the things to check for:
1)  Make sure the engine is in good tune - new plugs, cap and rotor.  Wires in
good condition too.  After running the engine for a while, pull the plugs and
read them.  They sould all be the same color - light tan. 2)  Check for vacuum
leaks in intake tubing and injector o-rings. 3)  Do a compression test just to
verify you have no burned valves. 4)  Check O2 sensor functionality by probing
voltage output with the O2 sensor connected.  Peel back the connector to get
at the terminals.  Voltage should vary back and forth from ~0.2 to 0.8V. 
Exact numbers aren't important.  If you get a voltage reading and it varies
back and forth, it's unlikely the sensor is bad.
	If all these check out, you might need the shop to adjust the idle CO mixture
(I assume the screw is on the AFM hidden by an aluminum plug if it's like the
Bosch Spider).  And finally, one of the injectors might have a slight leak,
causing a low rpm problem.  But I'd check items 1 - 4 first before getting
involved with the AFM or injectors.
	Hope this helps.

Charlie

	

>----------------Begin Forwarded Message----------------<

Date: 04 Jan 2002 09:03:49 -0800
From: "Jeff Enderwick" <tje@domain.elided>
Subject: Re: failed smog :-(
To: "Charles Slayman" <Charles.Slayman@domain.elided>
Cc: alfa@domain.elided

Ok - here are the details:

          idle           2500     (max allowed)
HC(ppm)   124/(100)      56/(130) 
CO(%)     0.10/(1.00)    0.23/(1.00)
CO2(%)    16.2           16.6
O2(%)     0.6            0.1

Didn't get any NOx numbers.

Thanks!

Jeff

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