Failed Emissions. Looking for advise.

So, the '91 failed the sniff test today. Was too high on Hydrocarbons and too high on Carbon Monoxide.

Any advise would be appreciated.

 

Here, if you do your best to fix it. Say spend $600 on plugs, cap, rotor, O2’s, maybe a cat. You can retake the test and they will pass you....

 

In Colorado, it's no-cost for 10 days for the re-test. I'm thinking that I don't want to start throwing money at it though. Think I'll take it to a good shop I trust where they can diagnose it for me.
From the little bit of research I've done, it sounds like I have a rich mixture/incomplete combustion problem and poor ignition problem.
I was hoping that someone may know a bit more though. I've never had a vehicle fail emissions before.

 

When I lived in CA, I just paid for a fake one. Ask around and probably can find someone to hook you up.

 

It's worth doing a tune-up if it hasn't been done recently. Maybe replace the oxygen sensor(s). Check for vacuum leaks.

We used to run a fuel treatment and take it on the freeway for awhile before going to the testing station.

I didn't know anyone actually tested any more.

 

Oh yes, here in the land of nuts they still test. This is a shithole state.

 

In WI, we only test OBDII and newer. Everything pre '96 is exempt. Soo, if I ever decide to build a project car, you can bet it'll be a '95 or older.

 

Try a bottle of 104 Octane boost, add it into the gas tank and run around for a few make sure your engine is at full operating temperature. New plugs won’t hurt with that either.

 

2Toys, I hear ya. Colorado is turning into California now, and it isn't good.

Thanks for the comments guys. It was my Dad's vehicle and he bought it new. I've done a bunch of stuff already (see my other post "so far"), but haven't replaced the O2 or Cat yet. It's probably a good idea to spend the $40 on the O2 sniffer. Some premium gas/Octane boost wouldn't hurt either. I siphoned out the old (8 years) gas, but there's probably still some residual nasty stuff in there.

 

I just got mine through AZ emissions. I went to Advanced Auto parts and bought 10' of new vacuum lines to replace all the little ones. The Cat might be an issue but I'd replace the O2 sensor for sure (Napa-$60) as that is a culprit of running rich. It can be difficult to chase the exact issue but you just have to be diligent. There are a couple of videos about testing the EGR and vacuum modulator that might be helpful.

 

New Cat Converter installed. California approved type is required here in CO, as of Jan 1, 21.
Crap! New one was almost $800!!!! But, it passed just this morning.

Thank you all for the advise and comments!

 

next time do a fresh oil change before you take it in + some octane booster in the tank.
in ontario we run some camping fuel in it, it runs super clean, but obviously a lot more expensive than gas....cheaper than a new cat though

 

My cat was actually recalled by Toyota I got a letter and changed for free.....

 

And the rear springs...

 

Congrats! Did you keep your old converter? They're presently worth at least $250 in the scrap market

 

No, I did not keep the old cat. The interior of it was pretty much gone. Actually looked like it was manually removed with a rod or something. I think my Dad had some "work" done to the exhaust.

 

My "rule to live by" when it comes to a vehicle mis-behaving (after obvious checks like "is there fuel" and "is a fuse blown") is to DO A TUNE-UP (caps for emphasis.

Camping fuel, as in unleaded gasoline without alcohol? We can get that at the pump here. BUT it actually makes the engine produce more HC as alky is an "oxidizer" (has less carbon per molecule than the stuff gas is made of).

 

i think you'd find it under denatured alcohol. or you can use some E85 just for the test, its a lot cleaner. Change the oil right before you go to the test.