OK so am i supposed to have any tension on my throttle cable when i re connect it. I'm having some idle problems and wanna know what its is so..............
If i have no tension in my cable, ie not connected at all, will my car still idle. If it does will it idle normaly? Can i still adjust it with the TPS/BAC etc, to get it to idle perfectly?

Or Does it require some (slight) pressure on the cable?

Thanks

AUGie

 

You need some tension on the cable. The Haynes manual specs .04 to .12 inch of freeplay when the cable tension is properly adjusted. I just replaced the oil injector lines and that required removal of the air intake manifolds. Of course this required disconnecting the throttle cable.

When the cable was reconnected with no tension, very loose, the engine would not idle at all. I had to adjust the cable tension just to get the engine to run long enough for me to get out of the car and get to the engine bay before it died. Once I got enough tension to keep it running I could then make the fine adjustments and get the cable tension about where it needed to be. Then comes the TPS adjustment and others that will return the engine to a smooth 700-800 RPM idle range. It will take patience or someone that is very familiar with these adjustments. Also make sure all vacuum hoses are reconnected and tight. You'll never get the idle right if you have even a slight vacuum leak.

 

You don't need tension in the throttle-cable for the car to idle. It should rest on the throttle-stop/adjustment thing (found under your IC, augie). However, you should have some tenstion to get the best accelerator-pedal response.

Did you just get done putting it back together? I forgot what exactly you were doing...

 

Ok so i got two different ansewers thats not good.

The reason I wanna know if it will idle with no cable on it is to know if something is wrong. when i install the cable i have it with just a tiny bit of tension on it. It still will wiggle back and forth between the nut and the end of the cable(front to back on the car) with out increasing speed. Does this sound about right?

If the cable is not on it will idle below 600 and acts for all the world like a Vac leak.

So finding out for sure if it will idle and is adjustable without the cable is kinda huge for me right now.

I have checked everything i can think of with carb cleaner so i think i got all of the leaks. I have even ran it along the UIM to LIM joint as best i can and no increase in speed so even that lookse good.

Any one have a definate ansewer for me???

 

I do not have a definitive answer for you but I just had a similar issue. When i removed my throttle cable and eventually put it back on it was very slack. Get in the car and press the accelerator pedal all the way down and hold it there (no keys in the car...car not running). Pump it a few times . This should get the cable seated properly and back to where it was before.
Before i did the throttle pedal thing my car was idling at 2000rpm. As i depressed the cable a couple of times lightly i noticed the idle started to drop. Anway, my recollection is the idle is not dependent upon the cable tension. It sits on a rest so your cable tension should be ever so slightly slack. It states the setup in the FSM.
Good luck.

 

i think it will if your tps is adjusted right. im not 100% on that, but one of my throttle cables rattled off and it caused my idle to be kinda wacky. then again i have a bad tps. so it usually is kinda wacky.

Brian

 

Listen to the voice of reason.

 

You just contradicted youself and confused the original poster. Freeplay and tension are the opposite of one another; you can't have both!

The manual says you should have a small amount of freeplay, so there should be no tension on the cable with your foot off the pedal. Any tension will pull open the throttle and mess up the idle.

 

if you have to use tension of the throttle cable to keep the car idling, there is something wrong and the car needs to be fixed.

 

So Ice, does that mean that the car will idle properly with no cable. I seem to be in a very fine zone here. Its the tension thing that is driving me nuts. If i adjust the nuts that hold the throttle on so that the cable is really loose (which basically is emulating no cable) the car idles really low and acts like a vac leak. If it is supposed to idle ok with no cable this means that something is wrong. (my guess is a small vac leak that i seem to have missed) My vac pressure is 12 in/HG at about 740 rps.

Right now the cable is adjusted tight with just a little back to back wiggle room my idle is just a bit high but i can adjust it. I do how ever have concerns about the BAC. If unplug it, it does not lower the speed like it should. Also when i turn on the AC the idle drops but does not raise back up until I turn the AC off.

The reason I'm trying to find out if it will idle with no cable is that it will tell me which direction to go in. If the car idles with out the cable then obviously something is wrong, probably a vac leak, and i need to find it out. My fear is that it is a slight leak from the LIM to the block or from the UIM to the LIM as these where both removed recently and I am pretty sure that i have all of the hoses and such acounted for.

 

AFAIK, the car should idle perfectly fine without a cable on it. I've had a few times where I forgot to put on the cable when I was done with working on it, and it would start great, idle great, and then not go anywhere when I hit the gas I'd have to go with Ice on this one, if you're using the throttle cable tension to hold idle, something is wrong.

 

Great that is what i was looking for. Mine idles without the cable just nor really well. So i guess its time to start looking for a slight vac leak..


Thanx AUGie

 

or a misalign TPS

 

to reiterate -

YES your car should idle without the throttle cable connected. It should idle at about 800 rpm. if it does not adjust the idle screw until the car does as per the haynes / (any) shop manual.

once idle is in spec search out vac leaks (if they exist) set your tps properly, check and make sure the BAC valve works and it not clogged or stuck, make sure your tps doesn;t have any dead spots with a multimeter, make sure the signal from your afm is correct with a multimeter.... wait what am i doing I'm pretty sure setting your idle properly is covered in the FAQ or in the Archives.

jana,
TR

 

Yes all of this is covered quite wellin the FAQ and here http://www.teamfc3s.org/info/articles/idle.html.

Its just that .04-.12 inches of play that was screwing me up. now that i know, i can readjust my cable and trouble shoot a little better.

TPS is set to about 1 ohm and shows only one light with the two light method it doesnt seem to have any dead spots in it.

I've done some preliminary tests on the BAC but will check it better in the next day or so.

How likely is a small leak from the UIM or LIM? i used brand new gaskets and they are torgued down pretty good so..........

 

Not likely--it's gotta be something else screwing up your idle. What are you trying to set the RPM's at? You said that the idle "smoothed out" when you had tension on the T/C, but that probably just meant it smoothed because the idle was raised slightly. Have you set the timing lately with a gun? That really helps to work out the last kinks when putting a car back together.

 

Car should idle fine with no tension on the throttle cable. Check the TPS again.
I just had the opposite problem. My car wouldn't idle right until I found the cable to be a little too tight...

CW

 

Just closing out the info for this thread. It turned out my BAC system was burned out in the ECU. After much testing I found out that a worn wire shorted and killed the transistor inside it. Tension is adjusted properly and the car will indeed idle even without the cable on.

BTW bac probs and vacuume probs are very similar in symptoms.