This is topic why dose my idle keep surging up and down for a few seconds every time i start it up? in forum Tech Talk at Northern California Ford Owners  .


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Posted by phat50 (Member # 1998) on :
 
it gose up and down and up and down and want to shut off for a few seconds then it will idle fine,what could it be?i have eldelbrock rpm intake,gt-40 heads,e303 cam,1.7 rockers,70 throttle body,and some other stuff,what could it be?
 

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Posted by Cobra5.0Jeep (Member # 1482) on :
 
do you have a K&N filter? I heard if you use too much oil on it some of the oil will be sucked back into your intake and get all over yuor MAF wire and the computer will get false readings from the MAF and won't know where to put the idle

When mine did that i reset the idle and it seemed to stop doing it

[ January 29, 2004, 08:24 PM: Message edited by: Cobra5.0Jeep ]
 

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Posted by JEO (Member # 2918) on :
 
probably your idle motor!
 

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Posted by phat50 (Member # 1998) on :
 
how do i reset my idle?
 

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Posted by eighty8mclaren (Member # 2751) on :
 
Take a look at this website this could be the problem, if not it is very good to do this anyways. http://www.fordmuscle.com/archives/2002/01/tenpin/index.shtml
 

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Posted by DropTopFox (Member # 1689) on :
 
hmmm I start my car up and the idle sits at like 1200 for about 15 seconds and then drops down to 1000. I always thought it was because the oil needed to be distributed throughout the motor
 

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Posted by 87 Saleen (Member # 1549) on :
 
haha mine does something similar to this too. No big deal.
 

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Posted by AL STOCK (Member # 1852) on :
 

quote:

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Originally posted by 87 Saleen:
haha mine does something similar to this too. No big deal.

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Yeah no biggy... Everytime it does it to mines i just look @ it as "PONY" waking up
 

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Posted by v-town coupe (Member # 2771) on :
 
i had the same problem right after a cam swap and i bought this iac plate from brothers performance and it took care of the problem but i have never had to use it before and ive done plenty of e303 cam swaps with out using this plate before iv even done a z cam with no prob.
 

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Posted by CMELEVU (Member # 2563) on :
 
I kind of had a similar problem with mine as well. Car wouldn't stay running when cold. Took off the idle motor on the side of the throttle body, cleaned it with some carb and t.b. cleaner. Seemed to help. Then I turned my c&l mass air meter housing on its side and the idle smoothed out. I could still tell that there was something not working right, but alas my motor seized before I could really find out what it was. I'm gonna have to try that ten pin connector adjustment when I get it running again.
 

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Posted by white1990stang (Member # 2307) on :
 
i just adjusted my tps sensor from .88 volts to .95 and it made a world of difference!
 

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Posted by castor (Member # 2765) on :
 

quote:

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Originally posted by phat50:
it gose up and down and up and down and want to shut off for a few seconds then it will idle fine,what could it be?i have eldelbrock rpm intake,gt-40 heads,e303 cam,1.7 rockers,70 throttle body,and some other stuff,what could it be?

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quote:

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Originally posted by white1990stang:
i just adjusted my tps sensor from .88 volts to .95 and it made a world of difference!

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what is the tps sensor and how do i adjust it?
 

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Posted by 94gt (Member # 3060) on :
 
Summary:

What is the TPS?

Sitting on top of your throttle body there is a sensor that relays to the computer the exact opening position of the throttle butterfly. In other words, how far do you have your foot into the accelerator pedal. In technical terms the TPS is a low-voltage potentiometer. Based on the position of the throttle and other factors given to it, the computer will decide how rich the fuel mixture will be at any given open throttle point.


Why mess with the TPS?

Well, based on the information given above it is easy to understand how important this sensor is to your Mustang's performance. It is important that the computer gives the correct air and fuel mixture at the right time. If your TPS is off (or bad), the information (voltage) that the computer gets will be inaccurate. The tuning procedures in this article are very simple and the potential for the TPS to be off is significant, so why not tune your car the right way and get the most out of it.

Details:

Tuning the TPS

When you tune up your Mustang (wires, plugs, timing, etc.), the checking/adjustment (if needed) of the TPS should always be included. You will need a Phillips screwdriver, a pin, and a voltmeter that can read low voltages accurately. Here is the procedure:

1) Loosen the two screws holding on the TPS, (The screws can be very stubborn, so make sure you have a good quality screw driver that fits snug and has a long handle for lots of torque, or you might strip the heads) just enough to able to swivel the TPS with force.
2) Pierce the "GREEN" wire with the pin and hook the positive (+) lead from the voltmeter to it.
3) Ground the negative (-) lead from the voltmeter. Use a good ground, like the engine or other grounded metal source.
4) Turn your ignition key to the run position, but do not start the vehicle
5) Rotate the TPS until you achieve .98 to .99 Volts (For stock or slightly modified engines).
6) Tighten the screws on the TPS and recheck.

Troubleshooting

If the maximum or minimum voltage you can obtain is close to the above recommended voltage setting (.98-.99), but the TPS just won't turn enough to get it right, you will have to modify the TPS. If you get a very low voltage reading, make sure you have an accurate voltmeter and your connections are solid, if so, you need to replace your TPS. If you have no voltage, you have a bad connection or a bad voltmeter. Rarely, if never, will a TPS be in such bad shape, especially if your car still runs good.


no, i didnt write that, but i got it form here...
http://www.allfordmustangs.com/Detailed/581.shtml

give it a try!
 

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Posted by white1990stang (Member # 2307) on :
 
will the reading be different if you adjust it with the car running cause thats what i did.
 

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Posted by shiftylx (Member # 2670) on :
 
well, my idle problem happens when i push the clutch in when i am driving, the idle will shoot up to almost 2000rpms, and then slowly going back to 800 but sometimes it stays at 1000 or slightly above it. does anyone have a simple fix for this?
 

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Posted by phat50 (Member # 1998) on :
 
so can anyone help me with the surging idle only when i start it?have anyone ever had this problem and fixed it?i know this is normal but theres got to be a way to fix it,its like it wont do it in the morning when i wake up to go to work but after its running i stop and get gas and start it back up and there it gose,then after a couple seconds then its like the computer startes reading it and idles fine,it dosent idle to low or to hight its just perfect,its onley when i turn the car off and start it back up it will go up and down and want to shut off if i dont keep my foot on the gas,there has got to be a cure for this other than a chip,i even got the little idle kit from ford and dident do anything but let me set the the idle without mesing with the throttle scruw.please any help.
 

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Posted by phat50 (Member # 1998) on :
 
can anyone help me?
 

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Posted by phat50 (Member # 1998) on :
 
well i went out to see if i can fix my problem with the idle surging badly only when i turn the car on and i started it and it started surging bad so i poped the hood and i was gong to play with the fuel presure to see if it would help and as soon as i took the vacume line off the regulator so i can adjust it the surging stoped and started idleing prefect,for some reason when its idleing up and down and up and down when i start it and i disconect the vacume line to the regulator it stops,dose anybody know what that might be,plese help,it surges with the vacume on for like 20 seconds but stop surging as soon as i disconect the vacume on the regulator and reconect it then its fine,what could it be???????
 

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Posted by 93PONY (Member # 60) on :
 
Might check to make sure the fuel pressure regulator isn't leaking fuel into the vacuum line. This happens sometimes.

Otherwise try this:
http://www.corral.net/tech/maintenance/idlereset.html
 

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Posted by GOT 50 (Member # 1960) on :
 
wish i knew but sorry to say cant help you?
 

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Posted by stoauto (Member # 2803) on :
 

quote:

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Originally posted by eighty8mclaren:
Take a look at this website this could be the problem, if not it is very good to do this anyways. http://www.fordmuscle.com/archives/2002/01/tenpin/index.shtml

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