O2 sensor (w/parts # and price!) and Spider NC emissions test results...

[JeffreyOlson@domain.elided]

A single-wire (non-heated) BOSCH O2 sensor is available at AutoZone for around 
$18!  Bosch part # is 0258001038.  It will cross-reference to a Bosch universal 
O2 sensor.  Just bought one for my '84 Spider and I believe the same unit is 
used for the GTV-6.

By the way, here's MY emissions saga:

'84 Spider w/good compression but a high-mileage head that lets a little oil 
past the valve seals when coasting down from high rpm's with closed throttle.

NO catalytic converter!  I have a Shankle header and test-pipe and have been 
trying to sneak the car through a NC emissions test.

NC emission limits are 220 ppm HC and 1.2% CO for '84 model year.  I can set 
the idle CO at 0.6% (stock specs) but get a high HC (around 400+ppm) or get the 
HC below 220ppm but end up with 2-3+% CO.  All this with the idle at 950 rpm (+ 
or - 50 rpm, stock specs).

Test involves a short 2,500 rpm conditioning run-up and then emissions tested 
at idle.

I have fresh oil, new plugs, new filters, and drive the shit out of the car 
before testing but still can't 'tweek' the idle CO and idle rpm to get the car 
to pass.  The high HC is most likely the result of excessive oil consumption 
and the lack of a catalytic converter rather than a 'rich' mixture.

No vacuum leaks or leaking cold start injector or anything else obvious to 
cause these readings.

I changed the O2 sensor and it had NO effect on emissions, mileage, or how the 
car runs.  The dead O2 sensor (I tested it at temperature with a digital multi-
meter) was not sending a signal to the ECU so it was in 'open' mode which is 
slightly rich.  

The new O2 sensor IS sending a signal to the ECU (within specs) but there is NO 
change in the idle RPM or emissions whether it is connected or not.  Glad I 
only paid $18 for the new O2 sensor!

Next try is 'Motor Restore' oil treatment and 'Guaranteed to Pass' fuel 
additive!  After that I'll break down and buy one of AR Ricambi's or Caribou's 
catalytic converters.  Fortunately with the header set-up I have, it will bolt 
in place where I now have a 'test-pipe' just like on the later Spica-injected 
cars and at much less cost that the OEM one-piece used on the later Bosch F.I. 
cars.

By the way, the Shankle header really perked up the Bosch F.I. Spider!  The 4-2-
1 stock exhaust manifold/converter is obviously VERY restrictive!  Car now 
ZINGS right to the redline in the lower gears!  Bit noiser than stock with 
a 'tinny' exhaust note but a noticeable improvement in performance.

Jeff

Davidson, NC

'78 Alfa Romeo Spider (For Sale, make offer!)
'84 Alfa Romeo Spider Veloce (Resurrected from burial behind trailer park!)
'88 BMW E28 535is (240K miles, best car BMW ever made!)
'91 BMW E34 535i w/RARE 5-speed (was mine, now wife's car, bummer...)

PS There are only TWO makes of cars in MY book...5-series BMW's and Alfas!


Date: Sat, 1 Feb 2003 22:22:32 -0800
From: "S Hooper" <hoop1128@domain.elided>
Subject: Re: GTV6 FAILED SMOG TEST

Hi all!

My friend just took his '84 GTV6 to get smogged.  The car failed and the
tech said that it was running too rich:  Check the O2 sensor.  Went to a
local parts store and the O2 sensors were listed at $240-375.

First, are we on the right track on checking the O2 sensor (the cat was
replaced last year)?  Second, is that really how much they cost!?!?!  Any
ideas?

Thanks to all of you, again!
Steven
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