Failed Emissions

[davegonz]

Well, I took my 1993 in to get inspected and found out that my county now does emissions testing as part of the annual safety inspection. My truck failed the carbon monoxide (CO) test of the Two Speed Idle Test (TSI)

High Speed Emissions (2590 RPM): 3.43 (1.20 Standard)

Low Speed Emissions (779 RPM): 2.64 (1.20 Standard)

My air filter might need to be cleaned (Toyota washable OEM), and my plugs are a little over a year old. It's also time for an oil change. Oh yeah, 1993 vintage plug wires. If I clean/change these items, could it lower my CO readings? According to the state's site, CO is caused by "A rich fuel mixture can cause high amounts of carbon monoxide, which can occur when there is too much or too little air reaching the combustion chamber."

Last night I was snooping under the hood for loose vacuum lines and noticed I was missing the wing nut on the air cleaner assembly. Could that contribute to the high CO reading?

Anyone have any ideas? I searched and found Semlin's post on what he went through, but I would like to hear any other new ideas.

Thanks,

 

[mmw68]

David,

My FJ62 did the same thing, it tirned out to be a leak in the exhaust manifold gasket. The air leak caused too much Air in the system..

So - look for a leak. On my current FZJ80, my EGR pipe was cracked..again more air in to the system, Iam about to order one befor I have it inspected..

I used some Sea foam thru the system to find leaks...it turnes into white smoke, and I could see the leak.

 

[davegonz]

Hmm..I think I might have some Sea Foam in the garage. I'll give it a try.

 

[davegonz]

Forgot to add...I have no CEL's at this point.

 

[94 Newbie]

What's a CEL ?

Forgot to add...I have no CEL's at this point.

Not sure on the CO - I asked some questions on my Sub similar and got one response here.


How do they treadmill test these since they are full time 4 X's ?

Thanks !


Britt

 

[sportbiker929]

change your 02 sensors. thay can be bad with no CEL. Mine were.

 

[davegonz]

Check Engine Light

No treadmill here,just tailpipe sniffer at certain RPMs.

I was thinking about the O2's since they were last replaced in 1996.

Not sure on the CO - I asked some questions on my Sub similar and got one response here.


How do they treadmill test these since they are full time 4 X's ?

Thanks !


Britt

 

[alkaline747trio]

Replaced in '96 by oem or aftermarket? If oem, those are newer than most here, if aftermarket, they could be the issue. Go ahead and do a full tune-up with things that are over 4 years old, replace as many vac hoses as you can, and maybe advance the timing to burn the fuel mix a little better.

 

[davegonz]

1996 by OEM..according to CDAN. I guess I need to feed Dan's dogs this month.

 

[warpdriv]

It's a little bit on the expensive side, but a 4BT conversion would take care of your problem and may solve some you have not discovered.

 

[davegonz]

Hehehe...Jeff...don't get me started.

 

[davegonz]

Passed!!

Well, after doing a quick tuneup with parts from Dan the man, I took the cruiser in to get retested and it passed!!

The things I changed were:
1) Bottle of Redline Total Fuel System cleaner
2) Cap, rotor, plugs, plug wires
3) Air filter element
4) Oil filter and Rotella

Here are the numbers:

High Speed Emissions (2590 RPM): 3.43 (1.20 Standard) Second Test--> 0.03

Low Speed Emissions (779 RPM): 2.64 (1.20 Standard) Second Test--> 0.43

Glad it's done!

 

[cruiserman]

I'll bet it was a clogged air filter.