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I have been trying to do a little sleuthing of my own, and I am a bit of a loss on this one;

Casting number 7037535
Has POE.

I am sure of this much, it's a Pontiac OEM airhorn for a 1969-1970 casting;
But I don't know which one, or if it's a SR casting.

Can someone please let me know what this top is 100% correctly suited for?

Thanks in advance for helping me solve this one.
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I'm not as good as many of the guys on here, but there is a possibility that the choke coil is going bad. Just like anything else, it can wear out, so maybe its opening and then closing again instead of staying open. Something to look at.
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I'd try making adjustments to the spring tension and see if it improves.
Also make sure the choke pull-off is holding the secondary flaps tightly shut at idle and no slop in the linkage.  The pull-off should open in about 1.5 to 2 seconds from compressed to fully open.  Also make sure that it is holding vacuum.....Cliff
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Diagnose a Quadrajet carburetor problem / Re: 1977 Qjet coughs and sputters
« Last post by stushug on June 22, 2017, 04:08:54 PM »
Yes I did.
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Diagnose a Quadrajet carburetor problem / Re: '81 Long/Random High Idle(s)
« Last post by MP81 on June 22, 2017, 03:21:46 PM »
The choke does seem to operate right after you start it, but checking for 12V with ignition on would be an easy test.

EDIT: Couldn't get a real good reading on the connection to the choke with the ignition on (but getting a good reading on the battery wasn't easy either, so I'll take another stab at it tomorrow) - regardless of that, I'm glad that I checked it, because it definitely was barely attached (terminal was too "open" and loose, so I closed it up a bit, and now it is tight on the spade).
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Diagnose a Quadrajet carburetor problem / Re: '81 Long/Random High Idle(s)
« Last post by Frank400 on June 22, 2017, 03:00:01 PM »
Looks like and electric choke that is not working, or unplugged, or plugged but with no power (12v with ign on).
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Diagnose a Quadrajet carburetor problem / '81 Long/Random High Idle(s)
« Last post by MP81 on June 22, 2017, 11:40:18 AM »
Hello there!

Ever since getting the car ('81 Z28, LG4 305) last year, the carb has always exhibited somewhat odd/random behavior.

When you start the vehicle up, it jumps to high idle (maybe a little higher than I'd expect) until the choke opens and the idle begins to come down. However, at some point, you'll hear it change, and it'll start increasing - all the way to about 2500 RPM, if you let it.

The only real way to get idle RPM to drop back down is the rev the hell out of the thing, and at some point, it'll drop down to 750 RPM, where it idles like a champ, though it likes to creep up to about 1k after that...

Sometimes, when you rev it when it's up high doing it's "thing", they're very slow to drop back down.

I remember earlier this year (prior to putting the car up on stands to install my headers - where it is currently still sitting awaiting my lazy ass to install the new exhaust) I was messing with it, because it had gotten really bad after the winter. I'm no carb expert, so bear with me on the terminology/descriptions, but the "rear linkage" (separate from the main throttle linkage) seemed to exhibit exactly the same behavior if I pushed on it while the car was idling - same sound of suddenly rising RPM, etc. I thought I had fixed it by playing with that a bit, but it seems to have returned.

I need to give the linkages all a good coat of lubricant (since I doubt that's been done in...well, maybe never), but I'm not sure if that'll be the entire solution.

Any idea what might be the culprit?

Thanks,

Kyle
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Diagnose a Quadrajet carburetor problem / Re: 1977 Qjet coughs and sputters
« Last post by Cliff Ruggles on June 22, 2017, 01:49:43 AM »
Did you install the new secondary plastic cam and spring from the kit?
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Diagnose a Quadrajet carburetor problem / Re: Idle circuit screw response
« Last post by raf2330 on June 20, 2017, 08:54:07 PM »
Blazer74, thanks for the response. I won't drill plates. I'll have time this weekend to pull the carb and check out the bypass channels. What you've suggested makes more sense to me now after reading a lot more this week. Will post findings. Thanks again.
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Diagnose a Quadrajet carburetor problem / Re: 1977 Qjet coughs and sputters
« Last post by stushug on June 20, 2017, 05:29:29 PM »
Yes. If traveling at lower speeds and I go wide open, the car starts to sputter, it has even stalled out a few times. As the rpms rise, it behaves a little better, but it never fully recovers. When it's acting like that, if I back off the throttle just a bit, the problem mostly disappears. As long as it's at full throttle though, the problem persists.  Thanks for the help so far, Cliff!
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