So the question is what to replace. The cats look original but I don’t think that is all. O2 sensors? A tuneup?
Not shockingly failed emissions (1 Viewer)
- Thread starter Brighton9280
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I'll be that guy.
Do a search for emissions. You'll find there's a "procedure" to do to make sure you pass first time, assuming you've done a few things.
Do a search for emissions. You'll find there's a "procedure" to do to make sure you pass first time, assuming you've done a few things.
iptman
SILVER Star
I'll be that other guy.... Totally not enough information. What year, what codes, etc.
What are these emissions tests y'all keep taking about? (I'll be that guy - Thanks Jesse Ventura! )
Brighton9280, Take a photo of your failed emission form that your state testing station gave you and post it here. That information will help us alot in forming a course of action to help you.
I’ll be another guy. Post up your emissions numbers and what is failing and by how much. Otherwise, there is nothing to go by except is your check engine light on? Are there any OBD-II codes set (if the year of your truck is appropriate). I other words, more information please.
- Thread starter
- #7
No codes, it’s a 92
- Thread starter
- #8
No codes, it’s a 92
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- #9
Oh and I’ll post the results tomorrow, it’s out in the 80, when I get gas
Show us your emissions test print out. What failed? CO, NOx, etc? and by how much?
:edit: late to the party
:edit: late to the party
- Thread starter
- #11
The results should be attached. Failed for carbon monoxide. Limit is 25 and I was just a wee over at 77
So it is only failing CO, which means it is running rich. Either too much fuel or too little air. Check for a dirty filter or obstructed air duct first. It could also be a leaky injector bad MAF or oxygen sensor or a number of less likely things. A more efficient catalyst would leap, but it is probably not the cause.
It is also ironic: Failing CO in CO.
It is also ironic: Failing CO in CO.
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- #13
Brand new air filter, so I can strike that one off. Hope it’s not the maf, I’ve seen those are spendy little suckers
Brighton9280 since your truck is a 92 you have a vain air flow meter, not a MAF. Also Do you know when your trucks O2 sensors were last changed?
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- #15
Honestly, no. I bought it a couple of months ago. My guess is not in a very long while
If your O2 sensors haven't been changed in a very long time I'd recommend that you change them. Replacing them is part of an ongoing maintenance scheduled. Rock auto has Denso sensors for your truck for 35 and 39 dollars each.
1992 TOYOTA LAND CRUISER 4.0L L6 Oxygen (O2) Sensor | RockAuto
RockAuto ships auto parts and body parts from over 300 manufacturers to customers' doors worldwide, all at warehouse prices. Easy to use parts catalog.
www.rockauto.com
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- #17
Awesome thanks!
FWIW: I just had my '93 tested in preparation for registering it in Colorado. It passed. Here are the details:
| Emission | Reading | Limit |
| HC GPM | 0.5255 | 2.5000 |
| CO GPM | 17.5489 | 25.0000 |
| CO2 | 769.1860 | - |
| NOx GPM | 3.5205 | 4.5000 |
Passed the biennial emission test here in Colorado. Results (notice the changed limits):
| Emission | Reading | Limit |
| HC GPM | 0.5663 | 2.0000 |
| CO GPM | 10.7052 | 25.0000 |
| CO2 | 679.6037 | - |
| NOx GPM | 1.8138 | 4.0000 |
I wish I could say there's some secret sauce, but besides filling the tank with ethanol-free gas and mounting a set of dedicated emissions test wheels and tires, I didn't do anything special.
You still have all the EGR hardware on your truck?
