Automatic Choke

['84ranger]

I had to put my project on hold for several weeks. So many things came up so I couldn't work on it.

But I'm almost done!!

I got the carb rebuilt, put back on and the engine runs great. However, I am still at a loss about this automatic choke. I cannot tell if it's working or not. I know that it's not getting any power. I ran a multimeter to the choke wire and it got nothing. So I traced the wire back to the red connecter hookup (see picture 1) and it was unplugged. Makes sense that it wouldn't be working if it's not getting any juice!

So, to make sure that I didn't have a short in the wire, I ran a direct-connect from the part of the connector where the choke wire hooked up to the battery and then tested the choke wire (see picture 2). I got 12 volts. So I know nothing is wrong with the wire, I just gotta hook it up somewhere.

This is the main problem: I have to pump the gas a few times to get the truck to start. However, if I pump the gas, it knocks the fast idle screw out of the V slot, and therefore closing the choke plate. This causes my engine to race out of control when I start it.

So here's what I have to do to get the engine to start right:
1. Pop the hood.
2. Take the air filter off.
3. Hold the choke plate wide open
4. pull the throttle cable several times to prime
5. release the choke plate so that it falls back into the V slot so that the choke plate is still open.
6. start the engine

Again, if I don't hold the choke plate open, hit the throttle, then let the choke plate back down, it won't stick into the V slot. If I simply hit the gas it knocks the fast idle screw out of the V slot and that's horrendous once I start it cause the RPMs go crazy.


So some questions are ...

1. Where does this red hookup go to? I cant find any place where it hooks up to at. (pic 1)
2. How do I even tell if the auto choke is working? I have never messed with this system, so I don't know how to tell if it's even doing it's job.
3. Is it normal to have to pump the gas a few times for the auto choke system? Isn't the auto choke supposed to take care of that or does the auto choke system just control the amount of air?

QUESTIONS UNRELATED TO THE CHOKE SYSTEM:
4. where does this hookup go? (pic 3)
5. where does this other hookup go? (pic 4) [this and the other don't plug together. I tried ]
6. what's this thing and where does it go? (pic 5)

***Every picture is of something that is on the passenger side of the truck, and is right near the starter solenoid. I know that taking pictures of random hookups and wires can be hard to figure out what they go to, so that's where they're located if that helps out at all.***


THANKS FOR ALL THE HELP!

 

[strvger]

perhaps it would be best if you just changed it over to a manual choke. as for the other pics, i'm not too sure as mine has been duraspark'd and most of my wiring went away with that.
wish i could have been more helpful. good luck with finishing up your truck.

 

[kimcrwbr1]

Pic 1 is your test connector for pulling codes. there should be a grey/ wire in the harness over by the choke thermostat that is the power to the choke you should get a pulsing voltage to it after the engine is started and run for a bit. The initial adjustment for the fast idle is set the cam on the v notch for the high speed adjusting screw it is the on underneath and pointing back toward the firewall. turn that screw out until you get around 1100 rpm. Let me see if I can find the carb setting instructions that will show you pics. When the engine is cold the choke should slam shut when you push half way down on the skinny pedal. After you start it the pulloff should open the butterfly about 3/16 to 1/4 an inch and the high idle screw on the v of the cam under the choke. If you are running the feedback carb do not hook the choke thermostat to 12 volts or you will need a new one. The choke relay is controlled by the computer and gives the choke a pulsing voltage shortly after starting. That is the relay next to your battery there make sure the connections are all good and your a pulse out of the grey/wht wire. It is kinna a crap shoot on adjusting the choke thermostat I make it close the choke all the way first then start it up just make sure all the sensors are plugged in when you start or you will need to reset the computer by disconnecting the battery for 1/2 an hour. I just set the air filter housing to the side with the IAT sensor still plugged in. Once you confirm there is power to the choke plug it in and let it fully open while the engine is running. You must make sure the choke fully opens.

 

[kimcrwbr1]

Pic 1 is your test connector for pulling codes. there should be a grey/ wire in the harness over by the choke thermostat that is the power to the choke you should get a pulsing voltage to it after the engine is started and run for a bit. The initial adjustment for the fast idle is set the cam on the v notch for the high speed adjusting screw it is the on underneath and pointing back toward the firewall. turn that screw out until you get around 1100 rpm. Let me see if I can find the carb setting instructions that will show you pics. When the engine is cold the choke should slam shut when you push half way down on the skinny pedal. After you start it the pulloff should open the butterfly about 3/16 to 1/4 an inch and the high idle screw on the v of the cam under the choke. If you are running the feedback carb do not hook the choke thermostat to 12 volts or you will need a new one. The choke relay is controlled by the computer and gives the choke a pulsing voltage shortly after starting. That is the relay next to your battery there make sure the connections are all good and your a pulse out of the grey/wht wire. It is kinna a crap shoot on adjusting the choke thermostat I make it close the choke all the way first then start it up just make sure all the sensors are plugged in when you start or you will need to reset the computer by disconnecting the battery for 1/2 an hour. I just set the air filter housing to the side with the IAT sensor still plugged in. Once you confirm there is power to the choke plug it in and let it fully open while the engine is running. You must make sure the choke fully opens.

Fig 3 shows you how to adjust the v notch of the high idle cam after the engine is started the choke pull off should set the adjusting screw on the v mark then you adjust the 1/4 inch hex screw on top for the choke opening just under 1/4 of an inch. push the pedal to the floor once and the choke closes all the way start it and then tap the throttle it should then have those two adjustments and around 1100 rpm. The curb idle also plays a part in cold starts the proper order is set the idle air after the engine is fully warm then adjust the curb idle and at any time you can preset the high speed idle by manually closing the choke while pushing on the throttle so it sits on the v mark of the cam. Once you get the carb dialed in the final choke adjustment is done cold.

 

['84ranger]

Ok, thank you for sharing the information. Couple more things ...

1.) you said that the auto choke choke shouldn't get 12 volts, and should be pulsing. Does the auto choke only get power when the car is running, or even when I turn the key without quite starting it? Also, how often does it pulse, because I wasn't getting power at all for a few seconds.

2.) my V-notch has only 1 notch, not 2 like in the diagram. What do I do in that case?

 

[kimcrwbr1]

I am not quite sure when the computer tells it to open I am guessing when it is running. Just use the v notch you can see for the high idle. How did you adjust the carb the idle air and the curb idle. Take the air cleaner off and keep the IAT sensor plugged in turn the idle air jets out three turns from the lightly seated position. Open the choke all the way with the choke thermostat for now and snug it down. Start the engine and bring it up to temp. Unplug the idle control motor then turn the idle air screws out for the highest rpm you can get then plug the idle motor back in the motor should idle around 700 rpm. Turn the key off and the idle motor should fully extend this is the curb idle. Unplug the idle motor again and start the engine and adjust the position of the motor for your curb idle 900 to 1000 rpm works pretty good. Plug the motor back in and it should idle down. The idle screw on the side of the carb that holds the butterfly open should not be touching the throttle lever, you want it to keep the butterfly from closing too far when you let off the gas until the motor takes control of the idle. It is called the antidiesel screw on the feedback carb on a reg carb it is the idle screw. Adjust the idle air and curb idle now because they both affect the choke settings. While you have it running you can keep checkin the choke power wire and see what it is doing.