Carb trouble?

[mrzim4]

1986 C10 silverado 305. I got a California voucher for $500 to get it to pass smog. The shop I took it too is the same shop I've been using for a while. They said they got it to pass by tweaking the Carb. About two days after I got it back I was sitting and a stop light and the idle dropped and picked back up immediately. It did this a couple times then just dropped and started idling really rough. The truck drove just fine but after sitting at a stop light for a while it'll do that then start to shudder when I give it gas. Not really sure how to explain that just feeling like it gets really rough and doesn't want to speed up. I'm going to bet its the carb, friend at work is telling me it might also be the timing. Just seeing if I can get some backup on a solution. Thanks guys

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[bake74]

     The smog guys would not have timed it.  First get it timed properly.  Second they very well could have " tweaked " the carb to get it to pass Ca. Smog.  They most likely had to lean it out to get it to pass.  Does not mean you should leave it there to run it every day.
      Without giving it a full and proper tune up, you will only be guessing about the problem.  But for sure you need to have the carb adjusted so it runs.  Since they got it to pass, you can adjust the carb so it runs better.
      I have had to do this on a lot of older vehicles for people to get them to pass smog, then after wards I just adjust the carb back.  It doesn't mean that it is running bad, it means that Ca has very strict laws regarding smog and older vehicles.
      But to do it all right, like I said you would have to start with a proper tune up, timing and then move on to final adjustment of carb.
     

[mrzim4]

Alright cool thanks. I'll probably do that as soon as I get a free weekend. Then I get to pull apart my dash and redo the wiring for my gauges

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