1989 745T - LH 2.2

The idle CO is 4.5%, up from 0% last year.



I have googled and ran through the FAQ and have until Wednesday to fix. :0
Vacuum is now mostly steady (within 1in/hg) @22" after replacing plugs. I can see poor ignition wires/dist cap causing the extra HC, but the CO is rich mixture. I'd info appreciate where to start. Thanks!
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Big Swede: 1989 745T 234,000KM

Here's some data on my 1991 745 (non-turbo)

January 2005 test: (all values in "grams/mile")
HC: 0.28 Standard = 1.0
CO: 5.32 Standard = 12.00
NOX: 1.71 Standard = 2.5

March 2007 test:
HC: 0.15
CO: 4.28
NOX: 1.73

January 2009 test 1:
HC: 0.33
CO: 6.10
NOX: 2.52 (failed)

New plugs, cap, rotor, found a few suspect vacuum lines. Checked and found no error codes.

January 2009 test 2:

HC: 0.30
CO: 6.05
NOX: 2.77 (failed)

Bought a new Cat from IPD for $185 and installed. Never been changed before, car has 210,000 miles on it.

January 2009 test 3:
HC: 0.25
CO: 1.23
NOX: 2.07 (pass)

I didn't think a Cat had anything to do with NOX or CO, but it certainly helped in my case.

Good luck
123 in PHX