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81 CC carb issue?

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Old Apr 4, 2010 | 12:18 AM
  #21  
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congrats 81 pilot. i bet your all smiles now. its a free feeling knowing you have no ccc sensor,wiring etc etc to let you down .
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Old Apr 4, 2010 | 09:02 AM
  #22  
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Thanks for the offer Henry. I've been trying to find my dwell meter, but I'm thinking I let someone borrow it years ago and it never made it back. Not something I use much with new cars. If I can't find it I'll pick one up. Right now I'm thinking it's not the carb because it will go rich when starting and in open loop and lean out in closed loop. That tells me that the solenoid and metering rods are working. Per the shop manual I was able to move the soleniod up and down with no sticking. That's why I'm assuming the computer is telling it to go lean, which would probably be a sensor. I'll let you know what the dwell readings are when I find a meter.
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Old Apr 5, 2010 | 05:59 PM
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It was the oxygen sensor. I swapped it this afternoon and drove it for 3hrs. It ran the best it has in the 2 yrs I've owned it. I guess a computer is only as good as the data that's fed to it.
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Old Apr 5, 2010 | 09:55 PM
  #24  
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jr105,

Were you pulling any codes before you changed the o2 sensor? Just wondering.....Tim
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Old Apr 6, 2010 | 08:47 AM
  #25  
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I didn't try to read the computer codes and my Check Engine Light doesn't work, so I don't know if there was anything to read. The symptoms pointed to a bad sensor so I figured for $20 and about 15 min of work I would try that first.
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Old Apr 6, 2010 | 08:15 PM
  #26  
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Carb swap out sounds good to me, my 81 is running a bit rough too; I havent figured out what it is yet; so would consider a swapout perhaps
Has anyone had success doing the carb swap this in Calif. ? I know the conventional wisdom is that it wont pass smog ; but I thought (maybe assumed) they just check to make sure the smog pump is there and did the sniffer test.
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Old Apr 7, 2010 | 10:22 AM
  #27  
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Originally Posted by snilloc58
Carb swap out sounds good to me, my 81 is running a bit rough too; I havent figured out what it is yet; so would consider a swapout perhaps
Has anyone had success doing the carb swap this in Calif. ? I know the conventional wisdom is that it wont pass smog ; but I thought (maybe assumed) they just check to make sure the smog pump is there and did the sniffer test.
All of my experience is from a non smog angle. I have no emissions police here, so it all came off including the cat. I know there are tree huggers on here, but I grew up in the oil field, and go to refineries even now in my present job, that industry in 2 seconds polute more than my car will in forever and my trees are still green and they cause me more allergies than smog ever has. So I can't say if the swap would be good for a cali car or not....but it worked fantastic for me.
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Old Apr 7, 2010 | 11:11 AM
  #28  
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I'll come at this from a different angle. First let me say I know nothing about the computer controlled C3s. With that said it seems that you are faced with a number of problems that may or may not be due to sensors or the computer itself. I can see you troubleshooting this for a long time and changing out a lot of parts in a quest to get it right. All the suggestions so far are probably valid if you want originality. For me originality isn't a goal so I'd say go for an aftermarket EFI like the EZ EFI from FAST. Yes it's a little pricey but if you go that route you end up with a modern EFI throttle body system which includes a new fuel pump and it will be self tuning. If I ever chuck my carbs this is the system I'll use.
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