bounceing idle and stalling
03-01-2017, 09:11 AM
#11
5th Gear Member
Join Date: Jul 2012
Location: ohio
Posts: 3,628
I wouldnt mess with the Idle stop screw unless you thing it was actually moved before,,,, Instead loosen the TPS screws and adjust the TPS position only. I dont know if the TPS you have is slotted or not. Try to get it into the .93 .95 and you should be good. If its super charged you want around 1.0 volt.
03-01-2017, 09:30 AM
#12
2nd Gear Member
Thread Starter
Join Date: Nov 2013
Location: ga
Posts: 273
yeah it has been messed with, the guy that installed the stage 2 comp cam's in it couple years bk did ,because it wouldnt idle ,wish he would have left it alone on that and tuner would have solved that, that why i said i may need to lower idle and it should put the tps voltage bk down also at same time? tps on my car is not slotted ive herd of people rounding the holes out bigger , but i hear that thats a bad idea not sure
03-01-2017, 03:34 PM
#13
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Join Date: Jul 2012
Location: ohio
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yeah it has been messed with, the guy that installed the stage 2 comp cam's in it couple years bk did ,because it wouldnt idle ,wish he would have left it alone on that and tuner would have solved that, that why i said i may need to lower idle and it should put the tps voltage bk down also at same time? tps on my car is not slotted ive herd of people rounding the holes out bigger , but i hear that thats a bad idea not sure
03-01-2017, 05:11 PM
#14
3rd Gear Member
Join Date: Feb 2013
Location: PA
Posts: 556
NO,NO,NO adjusting the idle screw has nothing to do with that voltage, unfortunately Ford doesn't allow adjustment of the TPS.
You can try to back the two screws out on the TPS and try to move it towards the closed throttle blade position it may lower that voltage.
I've heard of people slotting the screw holes so they could adjust it.
According to Ford the voltage should be between 0.50 to 1 volt at idle. A higher voltage would increase the idle speed but wouldn't cause it to bounce.
After reading your post again i'm thinking IAC don't care if it is new i have read more than a couple of times even on this forum that the local parts store brands come out of the box bad and that the only way to make sure is to buy a motor-craft parts
If you have moved the idle screw you will need to start all over in setting the idle, the process is too long to explain youtube or Google it.
The TPS is a three wire system one being a 5 volt reference wire, one being the signal wire which send voltage to the ECU depending on it position and the third is a ground
Hope you get this figured out, good luck
You can try to back the two screws out on the TPS and try to move it towards the closed throttle blade position it may lower that voltage.
I've heard of people slotting the screw holes so they could adjust it.
According to Ford the voltage should be between 0.50 to 1 volt at idle. A higher voltage would increase the idle speed but wouldn't cause it to bounce.
After reading your post again i'm thinking IAC don't care if it is new i have read more than a couple of times even on this forum that the local parts store brands come out of the box bad and that the only way to make sure is to buy a motor-craft parts
If you have moved the idle screw you will need to start all over in setting the idle, the process is too long to explain youtube or Google it.
The TPS is a three wire system one being a 5 volt reference wire, one being the signal wire which send voltage to the ECU depending on it position and the third is a ground
Hope you get this figured out, good luck
03-01-2017, 05:35 PM
#16
5th Gear Member
Join Date: Jul 2012
Location: ohio
Posts: 3,628
lol Right,, thats what I said not to mess with it unless he is for sure it was moved before. But it will change the voltage if you try to turn it up and get more idle out of it,, unfortunatly thats not how you set the idle. The computer will idle the car where it wants to,, opening the throttle blade, just makes it harder for the computer to control with the IAC valve.
03-01-2017, 06:42 PM
#17
2nd Gear Member
Thread Starter
Join Date: Nov 2013
Location: ga
Posts: 273
yeah sux the guy messed with my idle screw , anyway adjusting the idle down will bring down the tps voltage, same as when you do a sweep test on tps you move the very lever that controls the gas feed with stop screw so idleing it down by stop screw should also bring down tps voltage also or raise it
03-02-2017, 04:44 PM
#18
3rd Gear Member
Join Date: Feb 2013
Location: PA
Posts: 556
This is all true but when you adjust the idle screw you are moving the throttle blade position and even though it may reduce the output voltage it also changes the base position of the blade and the ECU doesn't know what to do.
There is a procedure for setting the idle screw but it requires a scan tool.
Just one more thing Ford has KAM (keep alive memory) in the ecu take both the neg and positive battery terminals off wait five minutes then touch to two cables together this will drain all the capacitors and should reset the KAM,
I know your in the middle of trying to figure out what wrong but i have to ask were the cams worth the investment i been kicking this around and can't decide what to do
There is a procedure for setting the idle screw but it requires a scan tool.
Just one more thing Ford has KAM (keep alive memory) in the ecu take both the neg and positive battery terminals off wait five minutes then touch to two cables together this will drain all the capacitors and should reset the KAM,
I know your in the middle of trying to figure out what wrong but i have to ask were the cams worth the investment i been kicking this around and can't decide what to do
03-02-2017, 09:54 PM
#19
2nd Gear Member
Thread Starter
Join Date: Nov 2013
Location: ga
Posts: 273
Heck yeah cams were worth it for sure next time i think ill drop in stage 3's but stage 2 is very noticable rough idle and performance wize also is great after tune ,but best bang for my buck so far as been 410 gears ,so so far i have added the cam's ,headers o/r without cat xpipe , flowmaster's,bbk throttle body 78mm, and accell injectors,410's ,no noticable mpg drop either and most of all great bama tunes ,oh and american muscle window decal gave me a 10 to 12 hp j/k lol
heres car running right after cam install and tune
heres car running right after cam install and tune
Code:
https://www.youtube.com/watch?v=plph7G7l6SM
Last edited by tadpole1969; 03-02-2017 at 10:13 PM.