Here's my story...sorry kinda long...

I currently have a Holley Street Avenger 670 w/ electric choke installed on my 72. I purchased the carb new and installed about a year ago (run for less than 1000 miles). I have had no problems with the unit up until now.

The past several times I have started my car when the engine is cold (sitting for a couple of days) my choke/high idle does not seem to set right. Normally I would pump the gas twice and turn the key. The car would fast idle at about 1500rpm and the choke would slowly come off or I would blip the throttle to kick it down. Now, I pump the gas and the engine cranks/turns over but does not go into high idle. I have to keep my foot on the gas for awhile so it warms up and doesn't die.

Today I took off the air cleaner and did some tests. I noticed when I fully depress the gas peddle the choke plate will close but not fully. I also manually operated the throttle linkage on the carb and it still left the gap even when fully actuated. About 1/4 inch gap remains. I pushed on the plate with my finger and it would close completely but I had to push pretty hard to get it to close. When I went to pump the gas peddle again I noticed the choke plate returned to the 1/4 gap position. Turned the key and same thing..no high idle. I let the engine run awhile and noticed that the choke plate did gradually open.

I put a multimeter on my electricaly connection to the choke and I am getting power. My meter measured 14V so I'm not really sure where it's wired into, I think it should be 12V. I've had no problem with this exact same connection for a year so I don't think that's it.

Outside temps aren't that high. I'm in WI, and some of the times I've gone to start it's only been mid 60's out. So before I call Holley tech service I wanted to run it by the forum. Any ideas why my car won't start in high idle and why the choke plate won't go completely closed/flushed when cool?

Thanks for any input.

 

Have you tried to just adjust the choke a little to compensate for the warmer than winter weather?

 

he's probably right.

the choke and fast idle are related, but operate seperately.

go to holleys web page and get some diagrams and set up instructions. you'll find it to be easy.

 

 

I did check my instruction manual. It tells how to adjust if your choke is coming off to early or staying on too long. There is a section on how to adjust the high idle but my problem is my car doesn't high idle at all. I don't see the diagram for my carb on their website. Part # 0-80670

http://www.holley.com/TechService/Library.asp

The carb was working fine for over a year. The choke/high idle functioned in 90+ degree weather and 40 degee weather. I don't think it's an issue with the ambient temperature but I could be wrong

 

The instructions say to rotate the choke cap counterclockwise if the choke is coming off too soon and rotate the choke cap clockwise if its coming off too late. Since the chock plate isn't closing completely would I rotate the cap counterclockwise? What about the high idle? Any idea why it won't set and how to fix?

 

your high idle screw sets on a cam that moves with the choke to a certain degree and is adjusted by reaching under the linkage.

since it was working, and assuming that you have made no other adjustments, the choke is likely not moving the fast idle cam far enough to let the set screw hold your butterflies open enough. by increasting the choke (clockwise), you will allow the fast idle cam to do it's job.

for what it's worth, i usually disable my choke (on a holley) because i don't like the "wash" of the additional fuel. i can set with the car until the fast idle is enough - only needed in winter here.

click here - find the one that suits your carb

 

Well, I sent an email to holley tech. They responded that from my description it sounded like the choke cap went bad. They are sending me a new one. I'll see if that fixes my problem. They are sending me the new part no cost and no questions asked. Good service so far.