Failed emissions

[tommy854runner]

I'm just grabbing at straws here but I figured I would ask anyway. I have a 3.0 that had a egr code but cleaned it out a week ago and 50+ miles and no ses light since then and it seems to run a little better too. I failed emissions on the nox today, but the truck runs good, has a complete factory exhaust, and otherwise seems to be in good running order. One tech here is telling me to advance the timing and clean the injectors. Another one is telling me there is still probably something wrong with the egr. Any clues?? I have been driving around on a temp tag for almost 2 months now and need emissions. HELP!!

 

[ms018kmf]

Is the code a 71? I've chased a 71 several times this year. I think I've narrowed it down to an exhaust leak between the DS manifold and the pipe (trashed studs ). Random idea, drawing for straws here too.

 

[John Galt]

Add some biodiesel. That almost always cleans up emissions.

 

[tommy854runner]

Thanks for the reply's here. No ses light now so no codes. My bg chemical guy gave me some engine oil cleaner that he says works wonders and some pour in fuel additive. He was a little leary on the miles on the 4runner and using the oil cleaner but he has used them on cars in the high 100k range and he said they ran so much better. I think I might still have the same exhaust leak you were speaking of even though my exhaust shop said it was fine, but I don't think that would cause it to fail anyway. Keep the ideas coming guys, thanks again.

 

[Hypoid]

Cat could be plugged.

 

[tommy854runner]

Good idea about the cat. I can just check the pre and post temps outside the cat once the engine is warm correct?

 

[raydouble]

Add some biodiesel. That almost always cleans up emissions.

On a gas engine?

 

[tommy854runner]

Well, replaced the converter last week with a generic fit. My BG chemical guy also gave me some "tune up in a bottle" and also ran some GM injector cleaner through the intake and drove it a week. Passed with flying colors(for a 20 year old piece!)

 

[Hypoid]

Glad you worked it out, and thanks for letting us know.

Sucks to search and not find out if the problem got solved....

 

[tommy854runner]

No prob. The other effect of replacing the converter is I can put down my back window while driving now and not choke!