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Remove computer from 1981

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Old 09-19-2017, 11:17 AM
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tehjrow
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Default Remove computer from 1981

Ok, that's it, the ECU is coming out of this car. I bought the car not knowing about it and wanted something not computer controlled. The ECU I have works, but if it gets jiggled the timing goes nuts and the car dies. I took the ECU apart and cleaned up the connections a bit and it works better, but I can still move the ECU around and get issues. I ordered a remanufactured ECU from Orileys and got it yesterday. I moved the chip over to the new ECU and now the check engine light blinks super fast as well a super fast relay clicking under the hood. I moved the chip back to the old ECU and it still works there (chip is good). When the new ECU is connected without the chip I still hear the fast clicking. When the old ECU is connected without the chip I don't hear clicking. This leads me to believe the new ECU is bad.

Video with new ECU with chip in

So, after all that, I'm done with the ECU. I know I need to replace the carb and distributor and I really don't care about torque converter lockup, never take it on long trips and don't care about mpg. So, I think I have a few options with the carb.

1.) Quadrajet with no computer control (same intake manifold)
2.) Edlebrock or Holley 650ish (do I need a new intake manifold?)

What sort of vacuum distributor should I get?
Old 09-19-2017, 12:04 PM
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BB72
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Originally Posted by tehjrow
Ok, that's it, the ECU is coming out of this car. I bought the car not knowing about it and wanted something not computer controlled. The ECU I have works, but if it gets jiggled the timing goes nuts and the car dies. I took the ECU apart and cleaned up the connections a bit and it works better, but I can still move the ECU around and get issues. I ordered a remanufactured ECU from Orileys and got it yesterday. I moved the chip over to the new ECU and now the check engine light blinks super fast as well a super fast relay clicking under the hood. I moved the chip back to the old ECU and it still works there (chip is good). When the new ECU is connected without the chip I still hear the fast clicking. When the old ECU is connected without the chip I don't hear clicking. This leads me to believe the new ECU is bad.

Video with new ECU with chip in
https://www.youtube.com/watch?v=J9IJfg7kM-Q

So, after all that, I'm done with the ECU. I know I need to replace the carb and distributor and I really don't care about torque converter lockup, never take it on long trips and don't care about mpg. So, I think I have a few options with the carb.

1.) Quadrajet with no computer control (same intake manifold)
2.) Edlebrock or Holley 650ish (do I need a new intake manifold?)

What sort of vacuum distributor should I get?
I had an 81, replaced the stock hei and replaced the carb since you cant adjust it. With a holley you do have to change the intake. My car was stick so no converter issues.
Old 09-19-2017, 12:42 PM
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jim-81
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Take it out and get a new carb and distributor. Much easier in the long run. That is what I did and no issues.
Old 09-19-2017, 01:31 PM
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Antz81
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The ticking you hear is normal, the way the light flashes is not. I'd just get them to swap the ecu. (I assume you trying to read codes at this point if not the ticking isn't normal either)
Old 09-19-2017, 03:13 PM
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terry82
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I would first try to get a new ecu .if that fixes everything that would be the cheapest way .But if you want to change over to non carb control.then call speedway for a disributer.That is easy plug and play.a performer intake .with a edlbrock carb.http://www.speedwaymotors.com/Speedw...utor,1688.html
Old 09-19-2017, 03:59 PM
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TimAT
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The ticking you hear is most likely the mixture control solenoid in the carb. The check engine light, key on, not running should be steady on. That reman ecm is having issues.
How is the ecm getting "jiggled"? If the timing is going crazy, I'd take a look at both the distributor connector and the knock sensor. You didn't state that you had gotten any codes prior to the ecm swap. It won't be as easy, but tracking down the ECM issues may be cheaper than throwing pars at it.
Old 09-19-2017, 04:26 PM
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0Willcox Corvette
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You might try pulling the connector and cleaning the pins and terminals at the Ecm before doing anything. It's common for them to corrode (especially if the car has bad weatherstrips) and once they do you get intermittent issues
Old 09-19-2017, 04:54 PM
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tehjrow
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Originally Posted by Willcox Corvette
You might try pulling the connector and cleaning the pins and terminals at the Ecm before doing anything. It's common for them to corrode (especially if the car has bad weatherstrips) and once they do you get intermittent issues
I did that and it did make a difference, I think the plugs themselves are also corroded a bit, not sure how to clean them. Just super disappointing that the reman ecu is bad.
Old 09-19-2017, 05:40 PM
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TimAT
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Your local parts store should have some contact cleaner. (Radio Shack is gone). Spray the connectors with that and blow dry.
Old 09-20-2017, 12:26 AM
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CheezMoe
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HEI Distributer and a 4175 Holley. No need to change intakes and fully tunable! Yank it!

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