I need smog help (1 Viewer)

[fj62steve]

Okay - so I cannot get my 62 to pass smog. It barely does not pass with too high NOX levels. Guy at the place said try using better gas or my timing could be off.

Is this legit? Does anyone have any tips or tricks for me to pass? I have been battling this for a year now - I live in San Diego CA
Thanks MUD

 

[2mountainfish]

Just a suggestion, post your copy of the report and I am sure a 62 guru will be able to point you in the right direction. you gotta love Ca. smog BS..

 

[OSS]

High NOx usually is caused by a malfunctioning EGR valve. Either not opening, not connected, or carbon plugged passage. High combustion temps cause NOx to form. The EGR system lowers it. If the CO was OK, that shows that the catalytic converter works. Timing doesn't typically drift on the 3F-E. If the timing was off enough to create high combustion temps (too far advanced) the engine would ping.

I'd check the EGR system.

 

[Spike Strip]

 

[fj62steve]

What’s the story with that denatured alcohol? I’ve heard of people putting that stuff in before the test but also heard it could have side effects? Interested to know the fuel to alc ratio

 

[OSS]

Denatured alcohol can lower CO, but it
won't help lower high NOx. It usually makes it even higher.

 

[cps432]

If you have room to wiggle on the CO and HC and you’re just barely failing NOx try retarding the timing a bit. Factory setting is 7degrees btdc. I put mine at 5 degrees btdc and passed. This will lower your Nox but it will raise the CO and HC a bit.
For what it’s worth, I’m driving a 60 rather than a 62. Maybe the timing is set a little different with fuel injection. Either way, drop it back a little and try that.

 

[DFXR]

Denatured alcohol can lower CO, but it
won't help lower high NOx. It usually makes it even higher.

^ True story. Happened to a guy I know.

 

[Spike Strip]

You're asking for a friend, right?

20-30%

 

[fj62steve]

Here is my smog report. Nox measured at 837.
Got a new gas cap.
Really close to not passing CO at 15 mph.

 

[fj62steve]

Should I go in again with higher quality gas after driving around for a while and try again? Or is there something I should look at before? Nox passes at 25 mph but not 15 mph. Timing is at 6.

 

[Spike Strip]

I'm not advocating anything here ...

But, as stated, NOx results from high combustion temps... The can in the pic above is known to slightly increase burn temps, but when it burns it is almost toxic emissions free, when EtOh burns it releases CO2, H20 and HEAT - That's why it's used on boats for cooking in enclosed cabins!

E85 is 15% Ethanol.

Did you verify EGR is working properly ?

 

[cps432]

How old is your catalytic converter? Nox is way high. CO and HC are relatively high as well. What spikestrip is talking about would probably get you where you want to be... if you’re into that kind of thing. And trust me, after many months and failed attempts at doing it the “right” way, just getting it done is the final option.

 

[fj62steve]

Okay - I haven’t been able to completely figure out how to test the EGR. Kinda get confused when I read the threads on it, and don’t have a vacuum reader or any special tools.
I’d be into using the can if that’s the ticket

 

[Spike Strip]

Get the emissions FSM Free download HERE

That's for a 2F, but the EGR testing applies.

Detailed procedure as well as troubleshooting guide

 

[fj62steve]

I am not sure how old my catalytic converter is, definitely more than 4 years old

 

[fj62steve]

I tested the EGR, seems fine, engine dies with vacuum.

 

[db3]

You have a couple of options. Either become an expert on keeping your emission systems in top shape or find someone who can. I was fortunate that I had a ASE master tech who knew the old school emission systems very well, and was able to keep my vehicles smog legal. One of the things I recall he had to do many times on my various Toyota and Honda vehicles was clean off the carbon build up on the pistons. The piston carbon buildup can glow and create the high temperatures resulting in excessive NOX readings, even with the EGR systems operational. The old school fix was to use the GM top cleaner additive, but that was outlawed years ago. His solution was water injection cleaning. I recall he told me he had to use over two gallons of water to finally get an old 1985 22RE engine to pass. But as OSS commented, make sure your EGR system is fully functional, and if so, then maybe try the water cleaning procedure. Unfortunately it is a bit more involved with an EFI engine.

 

[OSS]

All of your other numbers are borderline fail. That's unusual for a 3F-E.
The fuel injected 3F-E usually passes these tests no problem. The next suspect are the catalytic converters. They seems like they're not doing anything. If they're original- then they're highly suspect.

 

[fj62steve]

An update to this thread I started...
I PASSED!
For my Nox, the bad EGR modulator was replaced. Nox went way down. But shot my other numbers up and wouldn’t pass.
Changed the spark plugs and everything passed well.

Thanks everyone for your input it really helped me out.