Adjusting CO levels

[sab]

Is there a simple way to adjust the CO levels on 94 model 1.8?

Car is running a little too rich and I've been told that on some cars you can tune CO levels to not let it run as rich.

I believe a CO meter is stuck in the exhaust to measure exhaust levels and adjustments made somewhere on airflow meter or inlet manifold.

Anyone played around with this?

[Matty]

High CO emissions are a result, not a cause, of running rich.

[sab]

Probably could've worded my post a little better....

By measuring the CO emmissions out of the exhaust, you get an idea (reference) of how rich the car is running. After adjustments are made, you can measure if the tweaking is working or not.

My question - Is there any adjustment that can be made on the AFM or intake manifold that can change CO emissions?

[Fatty]

i assume yr talking about the o2 sensor. my car runs a bit rich on startup, until everything has warmed up (you can certianly smell it when you have the roof down). sounds like a similar scenario to yours. i was told that this is a sign that my o2 sesnor is worn out and needs replacing.

[sab]

i assume yr talking about the o2 sensor. my car runs a bit rich on startup, until everything has warmed up (you can certianly smell it when you have the roof down). sounds like a similar scenario to yours. i was told that this is a sign that my o2 sesnor is worn out and needs replacing.

Talking about anything other than the O2 sensor, which will also affect things until the car warms up. Mine was replaced, but still have an over rich mix and high co emissions.

[JBT]

It could be some doover in the intake system feeding bad info to the ECU or I suppose it's possible that it could also be the ECU itself. I don't think there are any adjustable things other than some after market fuel regulator. However, the car should run at the correct mixture with OEM bits.

Do you have one of those \"wet\" air filters? I've heard that they can sort of leave an oily mist on the AFM sensor and thus cause false info to be sent to the ECU.

Can you swap your ECU with a known good one to see what happens?

[Russellb]

On the 1.8 there is no easyway to adjust the CO%
you could try backing off the timing like Steve 818 said
Either that or an aftermarket ECU

[Matty]

Probably could've worded my post a little better....

By measuring the CO emmissions out of the exhaust, you get an idea (reference) of how rich the car is running. After adjustments are made, you can measure if the tweaking is working or not.

My question - Is there any adjustment that can be made on the AFM or intake manifold that can change CO emissions?

Back to my original post, don't bother looking at CO levels. It's a side-effect, not a primary effect.

Your "problem" as stated in this thread is that your car runs too rich. If this is true, then any shop with a portable wide-band O2 sensor that they can stuff up the tailpipe will tell you whether you're running rich. Any shop that is competent in tuning ECUs should have one of these. Maybe SelectMaz up in Epping?

However, I believe your original issue was the excessive black soot on the rear of the car. This may be being caused by other factors - possibly a faulty cat-converter. (As a side note, a collapsed cat may also explain the ordinary results you got on the dyno day... but I'm guessing). But it may be a damaged valve or a valve seal or something else...? I don't know.

In other words, I'd be very carefully working to find the root cause of the exact problem you have (and fix it), rather than trying to bandaid the side-effects.