Ideas on Failed Emissions

Owner of (92 4WD Toyo Pickup 3.0L V6).

I just failed emissions and am trying to make my truck pass myself.
I have incredibly high CO and moderately high HC. Low NO.

I have done the following things:

1.) Pulled the oxygen sensor and tested it according to :

[url]http://www.unofficialbmw.com/all/engine/all_o2sensor.html[/url]

.... It passed. Also I have no check engine light with it connected.

2.) Verified no massive vacuum problems.
3.) Banged against my catalytic converter and heard no rattling.

What are some other things I should try?

Thanks,
Lloyd

Sure sounds like it's running rich. How do the plugs look? If one
plug looks more carbon fouled than the others you could have a bad
plug, ignition wire or distributor cap. I presume the engine
temperature is normal and not running cold as an open themostat could
cause the coolant to be cold enough to keep the mixture rich. Good
luck. Al
nfirtaps wrote:[color=blue]
> Owner of (92 4WD Toyo Pickup 3.0L V6).
>
> I just failed emissions and am trying to make my truck pass myself.
> I have incredibly high CO and moderately high HC. Low NO.
>
> I have done the following things:
>
> 1.) Pulled the oxygen sensor and tested it according to :
>
> [url]http://www.unofficialbmw.com/all/engine/all_o2sensor.html[/url]
>
> ... It passed. Also I have no check engine light with it connected.
>
> 2.) Verified no massive vacuum problems.
> 3.) Banged against my catalytic converter and heard no rattling.
>
> What are some other things I should try?
>
> Thanks,
> Lloyd[/color]

[toyomoho]

Excessive CO usually results from rich air/fuel ratios. Check any items that can cause the engine to run rich.

High fuel pressure at injectors
Leaking fuel injector(s) including cold start injector (if you have one)
Gasoline in the crankcase
Plugged PCV valve or hose
Bad sensor(s) causing the ECU to drive the fuel/air mixture rich such as O2, coolant temp and throttle position sensor.

A higher HC may be due to misfire.

Might check the computer for codes, just in case the check engine light was not triggered.

toyomoho wrote:[color=blue]
> Excessive CO usually results from rich air/fuel ratios. Check any items
> that can cause the engine to run rich.
>
> High fuel pressure at injectors
> Leaking fuel injector(s) including cold start injector (if you have
> one)
> Gasoline in the crankcase
> Plugged PCV valve or hose
> Bad sensor(s) causing the ECU to drive the fuel/air mixture rich such
> as O2, coolant temp and throttle position sensor.
>
> A higher HC may be due to misfire.
>
> Might check the computer for codes, just in case the check engine light
> was not triggered.
>
>
> --
> toyomoho
> ------------------------------------------------------------------------
> toyomoho's Profile: [url]http://www.toyotanation.com/forum/member.php?userid=59151[/url]
> View this thread: [url]http://www.toyotanation.com/forum/showthread.php?t=169044[/url][/color]

Guys, thanks a lot for your replies, I will try all your suggestions.