I have been trying to get past oregon emissions for a couple of weeks and just replaced my o2 sensor...



My hydrocarbons went up a lot from my last test and is 26x the legal limit.

My carbon monoxide went up a lot from my last test and is 6x the legal limit.

The lady at emissions place yelled at me to turn it off! Hahaha I guess my truck is pumping out the equivalent to agent orange.

The truck runs great, good power, timing is according to spec.

Any ideas on how my numbers could be so high?

 

Here's mine, it sat for 5+ years, put a fuel pump in it, changed fluids, drove it hard on the way to the smog shop to heat up the cat. The guy missed a few things on the visual inspection, but it passed the tailpipe test.

 

Regarding your failed tailpipe test...
Did you gut the cat? if not it should be glowing red hot with that amount of HC. Your running rich too. Check your Coolant temp sensor, check for misfire, check the catalytic converter, lean the mixture at the AFM if unsealed. You can further reduce the HC by retarding the timing a couple degrees, but set it back after the smog check. Replace the plugs and do an oil change should help too.

 

Hey bswarm, wouldnt advancing the timing make it run leaner? Or do i have it backwards?

 

It won't affect it that much. This is an old trick we used to do to get cars to pass, it only takes a couple degrees when it's close to passing. With those numbers he has a misfire or running so rich it's causing a misfire, the oil may be fuel contaminated too.

 

Here's a good reference of understanding tailpipe emissions...
http://www.crypton.co.za/Tto%20know/...emissions.html

 

Thanks for that. I don't think I have a misfire. Although I've never had one so I don't know what they feel or sound like. Would I know if I was having a misfire?

With numbers that high, does that indicate that there is some kind of fuel leak into the intake? Would the ecu dump that much fuel in if the sensors were telling it too?

 

A rough idle would be a symptom of a misfire. How's your gas mileage? With those numbers it's probably pretty bad. Do you have any performance mods? Could be a lot of things, leaking cold start injector or other injectors stuck partly open, ecm thinks the engine is cold, saturated evap canister, fuel in the oil, afm, etc. Any codes or engine light on?

 

The idle seems okay. No surging or stumbling. The engine shakes a bit but no more than my old 86 22re.
My mpg is 16.6
The engine has a mild cam.
I'll look into those.
I had 2 code this morning: 5 and 6 which are o2 sensor and something inside the distributor. I replaced the o2 sensor today and both codes went away.

It's also worth noting that my readings before I swapped out the o2 sensor were 800 on HC and 6.3 on CO.

 

The cam might have something to do with it. I had to sell my van because there was no way that built engine would pass smog, it had a lot of horsepower and easily smoked 30" tires. Still, it was running cleaner than your readings and it was carbed with no smog equipment. Does your oil smell like gas?

 

Yeah, I have no problem going back to a stock cam if I can get it to pass that way.
No, I pulled the dipstick out and it just smelled like oil.

 

Let me know if this sounds like a misfire.

 

Sounds ok, some valve tappet noise though. You might have to put the stock cam back in, replace the catalytic converter if it was gutted (I'll bet it was gutted for performance) It kind of puzzles me that it's worse with a new O2 sensor, might be a problem with it. That's a nice clean engine on the outside!

 

I'm going to have to find a stock cam.
The guy I bought it from says it's not gutted. But even if it's not and it's been running overly rich for 2 year, the cat will be pretty much dead and needing replacement right?
I did a test that my repair manual told me to do on the o2 sensor and it looked like the ecu wasn't getting much of a reading from the o2 sensor. I find it hard to believe that the new sensor is bad but it's not impossible.

 

Also... when the key is switched to on, should the fuel pump be on? I hear and feel fuel moving through the lines.

 

Also again... I noticed today that it's missing the charcoal canister and the egr has no vacuum going to it. I'm thinking that there may be some partial emissions deleting going on. Could that cause such high numbers?

 

The EGR only has vacuum when the throttle is open, no vacuum at idle is correct. Did the PO re-clock or modify the AFM? That may be why it's running rich. The fuel pump should not be running with the key on engine off. Did the smog check place fail you for the missing evap canister too or do they only do a tailpipe test?

 

I'm talking about no vacuum line to the EGR at all!
I don't believe so. It's still sealed.
That's what I thought about the fuel pump... that's weird...
No, just look for a cat and use a tail pipe sniffer.
I'm going to test the coolant temp sender and check out the cold start injector today.
Why do you think my fuel pump is on?

 

I think the best thing to do is ask the PO what he's done to the truck as far as modifications for performance. It'll be a lot easier when we know everything.

 

He doesn't know much but I keep asking him as things come up. He is still responding to text so that's good!

Here's an update:
Checked cold start timing switch and coolant temp sender and both are operating within spec. I also tested them at the ecu and same good readings.

I'm going check the cold start injector now and see if it's leaking.

Here are some pictures of missing emissions equipment

Missing charcoal canister



Broken bvsv



Missing EGR vacuum modulator



Do you think these missing items could negatively effect my emissions in such a way that gives me the terrible result I have.