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Old 10-08-2020, 08:23 PM   #1
conoco
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Help with Choke/idle Settings

I can't seem to set my electric choke correctly and wondering what I am missing. I have watched videos and played with multiple settings. Here is the problem

I am in Alaska and it is starting to get cold. Just installed 1906 AVS2 and it runs great. I will go out first thing in the morning my truck will fire right up. Goes up to about 1500 rpms which is where I have the high idle set so it warms up faster ( Specially when it starts hitting 0° and lower) it will run great and strong for about 2 minutes and then it will slowly start bogging down until it starts sputtering and eventually dying. I will go through that process about 2 times until I just keep my foot on the gas a little so it stays current and warms up. After it warms up it run great.

Here is what I have done so far.
Changed my timing to 8° advanced ( I have 20-22 vacuum at idle)
I have unscrewed the choke and adjusted it all the way to the top mark which from what I read will make it stay closed the longest?
I have played with my idle mixture screws and everything seems fine.


The only thing I can think of now is maybe I have to much fuel pressure? I have a fuel pressure gauge installed and it reads 6-7 psi. I had a Holley carb and switched to the AVS. That's the only thing I can think of now.

Like I said once it warms up it runs great. No hesitation, no missing, it rips through first ans second.

Just hoping someone might know what I am doing wrong or what I can start trouble shooting.

I do have 2 separate plug in heaters. ( 1 for the engine block and 1 for the transmission) If I parked outside I would use them however my truck stays parked in the garage. But thats not the point. I would like to leave it outside in cold weather and know I can fire it right up and it will warm up without me being there. Any help would be great. Thanks everyone.
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Old 10-08-2020, 08:51 PM   #2
RustyPile
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Re: Help with Choke/idle Settings

Quote:
Originally Posted by conoco View Post
I can't seem to set my electric choke correctly and wondering what I am missing. I have watched videos and played with multiple settings. Here is the problem

I am in Alaska and it is starting to get cold. Just installed 1906 AVS2 and it runs great. I will go out first thing in the morning my truck will fire right up. Goes up to about 1500 rpms which is where I have the high idle set so it warms up faster ( Specially when it starts hitting 0° and lower) it will run great and strong for about 2 minutes and then it will slowly start bogging down until it starts sputtering and eventually dying. I will go through that process about 2 times until I just keep my foot on the gas a little so it stays current and warms up. After it warms up it run great.

Here is what I have done so far.
Changed my timing to 8° advanced ( I have 20-22 vacuum at idle)
I have unscrewed the choke and adjusted it all the way to the top mark which from what I read will make it stay closed the longest?
I have played with my idle mixture screws and everything seems fine.


The only thing I can think of now is maybe I have to much fuel pressure? I have a fuel pressure gauge installed and it reads 6-7 psi. I had a Holley carb and switched to the AVS. That's the only thing I can think of now.

Like I said once it warms up it runs great. No hesitation, no missing, it rips through first ans second.

Just hoping someone might know what I am doing wrong or what I can start trouble shooting.

I do have 2 separate plug in heaters. ( 1 for the engine block and 1 for the transmission) If I parked outside I would use them however my truck stays parked in the garage. But thats not the point. I would like to leave it outside in cold weather and know I can fire it right up and it will warm up without me being there. Any help would be great. Thanks everyone.
As soon as the engine first starts from dead cold, the choke should open slightly - about 1/4" to maybe 5/16"... Does it?? If it doesn't, the engine will "starve" for air and die.. Adjust the choke pull mechanism that opens the choke after engine starts...
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Old 10-08-2020, 08:57 PM   #3
conoco
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Re: Help with Choke/idle Settings

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Originally Posted by RustyPile View Post
As soon as the engine first starts from dead cold, the choke should open slightly - about 1/4" to maybe 5/16"... Does it?? If it doesn't, the engine will "starve" for air and die.. Adjust the choke pull mechanism that opens the choke after engine starts...
I will try that. Thank you. I will post if it helps. So frustrating lol
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Old 10-09-2020, 09:11 AM   #4
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Re: Help with Choke/idle Settings

My experience with Edlebrock chokes (No AVS's though) is that their choke timing is wrong compared to a Qjet. They take too long to open up completely. They may work good on a cold blooded engine like a 440 Mopar but I have never been satisfied with them on the GMs I drive. The Edlebrock carburetor was never installed by an OE and as such never had to meet cold weather driveability standards that new car buyers demand. It has always seemed to me that the chokes they used were an afterthought.
That being said have you sat and watched the choke during the warm up process?
Is the choke plate slowly opening up as the engine gets warmer? It may be binding and not opening up completely.
Ideally you would fire the engine and the idle would come up to 8-900 RPM and then as the engine warms up it will rise to 15-1700 RPM once warm.
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Old 10-09-2020, 09:33 AM   #5
geezer#99
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Re: Help with Choke/idle Settings

X2
I haven’t seen or used a carb yet in my last 50 years that an automatic choke worked well on. That includes divorced, electric or hot air. They’ve all needed some tweaking. Some manual chokes also need tweaking.
The factory chokes were designed to get you started easily, warmed for 30 seconds and off you go. Not started and ran for 5 to 15 minutes so your butt is warm when you get in to drive away.

So spend a few minutes and watch your choke plate.
I’m betting you see it work like normal.
And yes I grew up with my dad’s cold blooded mopars.
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Old 10-09-2020, 09:46 AM   #6
i82much
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Re: Help with Choke/idle Settings

it could be stalling from a rich condition rather than a lean condition. first make sure you have full voltage to the electric choke, not using a wire that comes off the ballast resistor or something along those lines.

then i would suggest backing off the choke setting a bit to see if that helps. if it is set to stay closed as long as possible and it is zero degrees outside, that bimetallic coil is nit letting that choke flap open at all.

also suggest making sure heat riser passages in head and intake are not blocked, potentially adding or repairing heat riser valve in exhaust, and maybe even adding a thermac air cleaner.
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Old 10-09-2020, 10:22 AM   #7
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Re: Help with Choke/idle Settings

Here's a video from Jegs that goes over tuning the carb pretty well. It's not specifically for the AVS, but its still essentially the same carb and everything still applies. https://www.youtube.com/watch?v=wR_AfQjyT-A&t=3s
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Old 10-09-2020, 10:22 AM   #8
Sheepdip
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Re: Help with Choke/idle Settings

I do have 2 separate plug in heaters. ( 1 for the engine block and 1 for the transmission) If I parked outside I would use them however my truck stays parked in the garage. But thats not the point. I would like to leave it outside in cold weather and know I can fire it right up and it will warm up without me being there. Any help would be great. Thanks everyone.

You could be very possibly icing up...try your plug in block heater in the garage and see if that changes anything.
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Old 10-09-2020, 11:27 AM   #9
i82much
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Re: Help with Choke/idle Settings

My understanding is that carb icing tends to happen on moist, cool days rather than really cold days - think fog on the windshield type of day. There are charts on the internet that show the conditions where it tends to occur, apparently aviators fight carb icing like crazy.

I am pretty sure you don't want to have your choke at the slowest opening setting in 0 degree weather. At least back it off a little bit and see if it helps.
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Old 10-09-2020, 07:24 PM   #10
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Re: Help with Choke/idle Settings

Warm your truck to normal operating temp and let it idle
Then see where the choke plate is at. It should be fully open!
Slowly move electric spring housing Until it’s just open.
Then you should be good. Simple and effective
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Old 10-09-2020, 07:28 PM   #11
conoco
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Re: Help with Choke/idle Settings

I really appreciate everyone's help! I will let you all know if I can get this going and fixed. Thank you for all the different trouble shooting options.
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