Like it says, my throttle kicker is always on, well almost always. Stock Rochester ccc carb, with A/c, auto. It;s always worked just fine until the past 2 weeks or so. For the first 5-10 minutes or so everything is normal then the throttle kicker comes on and holds the idle at about 1100 or so when i come to a stop, or shift into Park. Is i blip the throttle quick the idle will go down to about 700 for a split second then come back up. It's not sticking, if i unplug it the idle drops immedietly and it pulls the plunger in. If i plug it in the plunger pushes right back out again to bring the idle up. Like i said though it only does it after i warms up for a few minutes. It used to work fine and just come on when i turned the a/c on. The past few weeks though since it started doing this if i take off from a stop and give it gas slow it hesitates. If i'm cruising and i hardly step on the gas but keep by foot steady like 1/8 of an inch pedal it will miss and stumble. Its also stumbles if i keep the gas pedal light and steady and hit pot holes or drive on a bumpy road. If o floor it there is no problem at all. No hesitation at wot or anywhere above the "dead spot". I don't really know if i would call it a dead spot though because you have to hold the pedal steady to cause it to happen.
Not sure if the two problems are related, but they started at the same time, and that seems odd. Which is also the same time my choke wasn't kicking off from high idle. I replaced the choke heater and the pull off and that's fine now, both went bad at the same time, not sure why. If i've read other posts correctly the kicker comes on with a/c and on decell. Also with p/s switch, my car is 85 though and has no p/s switch. I just replaced the o2 sensor for a code 13, 44 and 45, The old o2 was falling apart and the wire connector actually fell right off at the sensor. No more codes afterward, but i noticed the exhaust was alot hotter at the tail pipes after i did that. I was hoping that was my problem, but it didn't change anything. Before when i drove the car for and hour and got home my tail pipes were warm to the touch, now after the same driving they are HOT, which has always been my experience with a normal car.
So my main concern is this stumble/cutting out at light throttle. I'm thinking maybe the TPS going bad? The MCS seems to be fine, EGR is not sticking throttle shaft is not sticking. Again the kicker is NOT sticking, it comes full on and full off when i unplug it. If u i turn the car off for a sec then restart it the kicker stays off for a few minutes then kicks back on.

 

UPDATE: today on my way to lunch from work my ses light came on for about 5 mins as im cruising along 35-40. Then it went out. I got home and checked for codes and got another 45. Climbing hills in O/D its clattering and pinging under light throttle, stops when i give it more gas. Also in O/D at about 40 it feels slightly jerky or stumbly at very light pedal still. Anything above that seems fine. And the throttle kicker is still coming out after it's warm.

I'm going to turn the adjustment down so it doesn't quite touch the throttle and drive back to work. I'll see if that makes any difference. I'm going to leave it plugged in though.

 

Check your TPS voltage at the curb idle setting. You may have to backprobe the B and C pins (connector has to be hooked up and ignition in 'run'. It should be around 0.40 volts and increase linearly to near 4.0 as the throttle is opened.

A TPS that fails will sometimes read an intermediate, constant voltage at certain throttle positions. This can keep the throttle kicker engaged and cause some hesitation at throttle transitions. Maybe not consistent with your lean stumbling and pinging, but it's the first place I'd look.

 

I backed off the kicker so it doesn't push the idle up anymore but not i seems to hunt for idle between 600 and 900 when cold, levels off when warm but same issues continue and keeps setting a 45 code just as it gets fully warm. Light stays on for 3-4 minutes or until i accelerate for a few seconds. I got another carb from a yard today too. I'm just going to swap and see if the symptoms go away. My carb has been acting up alot between the choke not kicking on at startup, pulloff going bad, choke not kicking off high idle, and this problem all within a month. I fixed the choke and pulloff issues, but i think it might just need a full rebuild, and maybe a TPS. I'll see what this other one does, it was only 20 bucks, so no loss if its in need of a rebuild too. At the very least i got an extra TPS to swap if it's good.

I'm going out to change them right now so i'll update you in a bit.

 

Well, i put the other carb on and couldn't get the idle down below about 800. I backed off the idle with the adjuster screw and the throttle lever isn't even touching it now but idle is still kinda high 8-900. Even if i pull the linkage forward i can't get the idle any lower. It's a junkyard carb though thats been sitting for years so i'm probably lucky it even runs. I tap the key though and it fires up in less than a second, my other one took 4-5 seconds of cranking and about 1/3 pedal to start.

The clatter and pinging seems to be gone, and there was no stumble or hesitation, but the first couple times a went WOT it wanted to stay about half throttle when i let off. I put in in neutral when it did that and tapped the pedal but the thing was running like 3k rpms. After blipping the throttle a few dozen times and lubing everything up i got it to run pretty much normal. The idle keeps sitting at like 1100 coming to a stop til i tap a couple times then back to 800/900. It seems my original carb has problems probably with teh TPS like i suspected. My original problem with the throttle kicked remains, even on the swapped carb. If i unplug it the thing retracts. And when i touch the connecter back on it makes a loud "SNAP" as the plunger kicks out and hits the throttle lever. I screwed it in far enough so it isn't really doing anything.

And i got another code 45 when i was letting the car warm up. So for some reason the car still thinks its rich for a minute when it warms up. It may be, but what are the chances both carbs would make it do that?

So now my question is why is it still giving me a 45, and how do a stop it from doing that? Also why wont this carb idle down any lower, I hate high idle? And why would my old one cause clatter, pinging, stumbling?

 

Damnit!!, New development. I went out to play with the car again after I ate and figured i would clear my ses code 45 which i thought it set off while road testing the carb. I checked the code just to be sure first and came up with the 45 again as well as 13 and 23. I just don't get it. Something has to be wrong other than the carb and the o2 sensor i just replaced.

**EDITED because i just realized i'm and idiot and did it myself by unplugging the MCS and TPS while i was messing around earlier then plugging them back in all while it was running because i was trying to figure out why it was idling high.**

 

Sounds like the primary throttle shafts are worn on the jy carb you picked up. With them open slightly (so the butterflys don't keep it tight) try wiggling the primary throttle shaft. Any play and it needs to be bushed.

The JY carb may, or may not, be adjusted correctly to your motor. If it's far enough out, the ecm won't go into open loop and it's probably going to throw the 45 code eventually.

Throttle kicker on both may be odd, but both may have a bad TPS.

 

I believe you meant, "...the ecm won't go into closed loop..."

 

This morning i got in the car, gave it a pump to set the choke, (it was about 55 degrees) and turned the key. Car started up in about half a crank and idled on high idle of about 1900 for about 10 secs until i tapped the pedal, then it kicked down to 11-1200 for about a minute. One more tap brought it down to 800 rpms or so. Left for work, no ses light, no problems at all except the throttle shaft does seem to be keeping it at like 1100 rpms until i blip it once to get it down to 800.

So i guess i should probably take both carbs apart, use my old carb body and shaft and throw all the other internals from the jy one in after a good cleaning. Does that sound like a good idea?

 

Stop digging inside the carb for now. Sounds more like the choke isn't getting fully open and that's causing your idle to "hang" around 1100. The choke linkage has a fast idle cam built into it so if the choke doesn't get FULLY open it will hang on the last step of the fast idle cam.

Choke is heated electically via the one wire connector that plugs into the round, black choke element on the passenger side of the carb. Is it getting full voltage while the car is running? Is the choke element working properly (they can go bad- their resistance climbs and they won't heat up like they used to).

Also, the idle speed will never drop until you blip the gas pedal. The throttle arm needs to be opened to unload the linkage and allow it to drop to a lower step on the fast idle cam. So, that's normal behavior (and totally unlike a fuel injected engine that has a separate IAC to instantly adjust the idle speed wherever the ECM commands).

Classic "choke not getting fully open" symptoms are as you describe- you can get it to idle down if you give it a hard blip, but the next time you open the throttle a little it hangs right back up on that last step of the fast idle cam.

 

It's opening all the way because i adjusted it when i first started it up last night. And after i give it a little bit of throttle and it hangs all i have to do it pull the throttle lever forward by hand. You can feel it stick. It does seem looser today though, i only had to blip it once or twice. If the spring was stronger it wouldn't happen.

 

Check the TPS voltage before going too much further. You can use a needle to back probe the connector. Engine doesn't need to be running to check, just in 'run'.

If the shafts are worn enough for the throttle to stick, it's going to have vacuum leaks that will cause intermittent idle quality problems.

Crap, that's like 20 or so times I've done that...

 

Yeah i'm going to check the TPS tonight and seem if it's ok or not. Seems ok though. I'm going to check the shaft and the dwell aswell. It's running fine though atm except for the sticking.

 

Also do a quick check while you'r under the hood- disconnect the throttle cable from the throttle arm temporarily and see if it starts returning fully down to curb idle by itself. Sometimes the cable itself is to blame or is mis-adjusted and running out of travel slightly before the throttle arm gets all the way home.