im new and need help with smog

[steve_925]

i have a 77 king cab with L20b. it keeps failing from too hi of NO. the first time i didnt know it but the timing was 27* advanced with a measure of 2600 NO(1592 being the max) then i dropped the timing to 11* and it measured at 1641, so it almost passed. the egr light has been on the dash, so i went and got a new egr valve from o'reilys. the egr comes with different washers, there is a list of numbers(that you find on the sticker on the hood), but none of them match with my number. is there there anything else i can do to get the nox down. i can bump the timing down 2 more degree, but i only get 1 free retest so if it doesnt pass this time its another $40. any help would be appreciated

[steve_925]

theres also a tiny vacume line coming from the big vacume line that goes to the booster that i cant find a place for it to go.

and the purge line coming from the charcole canister is just hanging there. where does it go?

thanx

[datzenmike]

I suspect that you are in California, you should fill out your profile with this detail. The EGR light is triggered by a counter that registers mileage and is a reminder to remove and clean the carbon deposits from your EGR, you don't have to replace it.

 

The small vacuum line goes to the AB (anti backfire) Valve.

 

The purge line from the charcoal canister gos to the and joins with the vacuum advance line to the distributor and from there to the vacuum source on the carb.

[steve_925]

 

The purge line from the charcoal canister gos to the and joins with the vacuum advance line to the distributor and from there to the vacuum source on the carb.

 

updated the profile.

 

the line on the canister marked dis. vc goes to the distributor vacume. the one marked purge is what im ot sure about

 

and where is the AB valve?

 

i was about to put the factory egr back on when i relized that the egr intake was solid carbon, so im cleaning that out and im just gonna put all the old stuff back on. will the light go off or how does that work?

[steve_925]

can anyone tell where the anti back fire valve is?

[datsunaholic]

The AB valve is behind the carb, mounted to a bracket on the manifold. When you pull the air cleaner, it usually pops loose. Its top hose attaches to the air cleaner.

 

This is a really bad picture, but it's the goldish-colored round stamped-steel thing behind the carb. It's loose in this pic.

 

[Nicholas7620]

I was too high on my NOX for my last smog test. I replaced the Catalytic Converter, the EGR and a check valve. It was enough to lower my NOX to pass the CALI smog test. Whew. :D