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Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

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Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Old 10-08-2018, 10:16 PM
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Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Iíve been battling a high idle intermittently all summer with my bone stock LG4 with the factory Canadian non-computer controlled Rochester Quadrajet. The car cold starts great, idles high for a minute or two as it should, then Iíll kick it down and itíll idle on the secondary idle position. Iíll start driving, and it drives well no hesitation or bogging, but as the car warms up the idle increases up to about 1400rpm (in neutral). Even once the car has been driven for quite a while the idle will remain high.

When I pop the hood and investigate I will find the choke partially on, still sitting on the secondary idle position. I can push the little choke lever down, and the car will idle down where it should, but as soon as I release it the little lever pops back up and puts the choke back on.

I took a couple videos and posted them here, hopefully theyíre more illustrative than my descriptionÖIn one video the car is running, and the other itís off. In both videos I am pushing down on the choke lever, and you can see it just springing back on.


I canít for the life of me understand whatís going on here? Are the linkages binding or something (Iíve sprayed them with carb cleaner a few times) somewhere? Or is the electronic choke element bad? Or something entirely different? Itís bugging me a lot since this car runs flawless otherwiseÖ.
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Old 10-09-2018, 09:45 AM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

first I do not use any carb cleaner any more. reason is it destroys the rubber/plastic and wiring insulation ..use a MAF cleaner or electronic cleaner.

with your video looks like the choke stove is open, pull off the power plug use ohmmeter the ohms should be around 20-25 ohms.. then measure the volts to it .. should be 11-12 volts engine on ..the choke does get internally damaged and then creates an open circuit so no heat is created to move the plate open ..

use electronic/maf cleaner to clean those links on the vacuum operated parts may need a small wire brush if some rust there.

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Old 10-09-2018, 07:10 PM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Ok, thanks, that's very helpful. Silly question, is the 'choke stove' the big round thing with the electrical connector going to it?
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Old 10-10-2018, 08:00 AM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Originally Posted by Firm84 View Post
Ok, thanks, that's very helpful. Silly question, is the 'choke stove' the big round thing with the electrical connector going to it?
yes that is the heater choke.. electrical power creates the heat so the internal spring when it gets hot causes the choke lever to open the primary plate.
the spring is bimetal so that is how the spring changes shape to get this to work.. no power it is not gonna work or if the connector has no resistance then no power will heat the spring. the rivets have to be removed if the choke has NO resistance like 20-25 ohms.. no volts on connector engine on check the CH fuse under the left side of dash. 20amp CH fuse
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Old 10-19-2018, 07:19 PM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Alright, finally got a chance to play with this a bit. The electrical connect is good, has full voltage (12V+) when engine is running. The choke heater might be my problem since I was getting wonky ohm measurements....cold is was measuring between 16-18 ohms, once the car had warmed up I unplugged it again and it was measuring around 4 ohms then.
When I drove the car today, it did take way too long to come off of the secondary idle, but it did eventually come up and the choke opened fully....after maybe 30 minutes of run time.
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Old 10-19-2018, 07:33 PM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*


Last edited by NoEmissions84TA; 10-19-2018 at 07:37 PM.
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Old 10-20-2018, 09:04 PM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

OK, did a bit more testing today after watching some videos on how to correctly use my multimeter to measure resistance (probably should've done that first....). Now, using the meter correctly, and testing from the tab where the electrical connect would plug in, to where the choke assembly body near where it mounts to the carb I am getting a steady 14 ohms of resistance. Does that indicate a good or bad choke heater? The choke heater is like $85 locally, and with shipping to me in Canada is similar if I buy online, so I am trying to avoid throwing unnecessary parts at it.

I also noticed today that at no point in the drive cycle (including a stone-cold start) did the choke light on the dash come on....I know I've seen it lit before, but not regularly, and definitely not today. What does that indicate?
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Old 10-28-2018, 04:32 PM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Replaced the choke thermostat today and the problem appears to be solved, drove the car a few times running errands and the choke has been working perfectly. Once I drilled out the rivets and installed the new heater/thermostat I reset the adjustments using this tech article from the Corvetteforum, very good reference if anyone ever needs it:
https://www.corvetteforum.com/forums...jet-choke.html
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Old 10-31-2018, 11:33 AM
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Re: Stock Non-Computer Quadrajet Choke Sticks - Need Help *w/ video*

Originally Posted by Firm84 View Post
Replaced the choke thermostat today and the problem appears to be solved, drove the car a few times running errands and the choke has been working perfectly. Once I drilled out the rivets and installed the new heater/thermostat I reset the adjustments using this tech article from the Corvetteforum, very good reference if anyone ever needs it:
https://www.corvetteforum.com/forums...jet-choke.html
good you did work it out as I stated , so the fix was not a big issue ...
these choke heaters do get damaged because of the high temps and the design .. over time this is a regular replace item ... if you have converters good to check it every oil change . decades ago I was not liking how GM riveted these in place . I fabricated the choke key so in summer less choke winter a bit more choke..

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