RPM Fluctuates while idling and bounces below 500 if revved up a bit
#21
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i had the fuel pump TSB fixed.. then i got a JLT II and flashed it with SCT XCal2-SF.. i've been strugling again for the past week
i just went outside flashed car to stock.. then flashed the tune back on, and disconnected the battery
i'm gonna keep the battery out for a while, then reconnect it, crank it up and leave the car idling out there for 15 minutes
let's see if i'll ever get to the bottom of this
i just went outside flashed car to stock.. then flashed the tune back on, and disconnected the battery
i'm gonna keep the battery out for a while, then reconnect it, crank it up and leave the car idling out there for 15 minutes
let's see if i'll ever get to the bottom of this
![Frown](https://themustangsource.com/forums/images/smilies/frown.gif)
#22
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well that didn't help.. idle RPM kept dropping below 300-200.
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
#23
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well that didn't help.. idle RPM kept dropping below 300-200.
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
![Icon Mrgreen](https://themustangsource.com/forums/images/smilies/icon_mrgreen.gif)
Congrats and happy driving.
#24
well that didn't help.. idle RPM kept dropping below 300-200.
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
finally, i removed the JLT, flashed back the stock tune and took her in for 25k KM service.
and at last.. she threw up a DTC code P0505.. IAC fault!!!
they changed my throttle body assembly, complete with the TB motor and TPS sensor.
came home, put the JLT back on, flashed Doug's performance tune, let her idle for a minute or two.. she sat there at 740 RPM purring like a tiger
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
switched on the AC.. for 2 minutes, and she sat there at 740 RPM
took her out for a "spin" all the way from 0 to 140mph (gotta love Dubai!) and the RPM was as good as it gets
at last.. i'm happy!
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
#25
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2Slack: i wish you did ![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
during those few months, i had to learn so many techniques to keep the car from stalling, and manually keep the RPM up at all times!
she's as good as it gets now.. i just went out for a cruise and was seriously grinning throughout![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
i almost missed how smooth she used to be, and now she's back
![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
during those few months, i had to learn so many techniques to keep the car from stalling, and manually keep the RPM up at all times!
she's as good as it gets now.. i just went out for a cruise and was seriously grinning throughout
![Big Grin](https://themustangsource.com/forums/images/smilies/biggrin.gif)
i almost missed how smooth she used to be, and now she's back
![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
#26
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darn search function works well;...shoulda tried it earlier:
my car started acting goofy today. moved the 09 down the driveway last night, strepped on it a bit, thought hmm, this things got some ***** (had only driven the 06 the last 2 days before), got me wondering if something was up with the 06...
this morning it ran fine, but still a little weak compared to the 09, but not severly different, just the throttle wasnt as crisp, less bottom end torque(odd as the 09 has 3.31s), then this afternoon, the 06 stalled 5 times, rpm surging from 3~400 up to 2000 when it DONT stall- no bottom end, feels like a 4 cylinder until RPM gets up over 2500, then maybe about half normal...
gas is a month old, still 1/4 tank, the first 3/4 ran fine so dont think bad gas (unless someone peed in my tank or something at work)...
seems like a TB issue in my little mind...got home plugged the scanner in, no codes, pulled the inlet off and worked the tb manually to see the feedback% from closed to wide open:
ABS TPS from 16.8% ~ 82.3% seemed pretty linear
REL TPS from 5.8% ~ 70.9% seemed pretty linear
ABS TPS B from 22.3% ~ 90.9% at half throttle, stays at 90.9 to wide open... is this a backup sensor for limp mode that wont let you get full throttle, or is the TPS just shot?
TB moves freely, looks clean, no trouble codes stored...dont recall the pedal sensors tag, but it went pretty close to 0-100% and linear.
thanks for any suggestions![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
Tim
EDIT-
did some reading, the non linear on the second channel is normal- I had swapped batteries a couple days ago, never had it above 50- didnt think about the relearning thing- did some more reading, requires 1~3 decelerations under engine braking from 60-40mph to recalibrate misfire sensors, think it mighta just learned a bad map, as I drove normally, but got on the highway for the first time since the battery swap, got off the highway accelerated to about 80 on this nice offramp, shut down and pushed the clutch literally right at works driveway. next drive leaving work it was all messed up- stalled for the first time ever just after starting, 4 more times on the way home, no power, idle all over the place...think the improper deceleration screwed it up, and it just tried to map some bad data...unhooked the battery/shorted the wire terminals for a few, hooked it back up, it was ok, idled fine, power still a little down...let it warm up fully, took it up over 60, coasted back to under 40 in third, its fine- first gear is awesome again!
man was it acting wacky earlier though
my car started acting goofy today. moved the 09 down the driveway last night, strepped on it a bit, thought hmm, this things got some ***** (had only driven the 06 the last 2 days before), got me wondering if something was up with the 06...
this morning it ran fine, but still a little weak compared to the 09, but not severly different, just the throttle wasnt as crisp, less bottom end torque(odd as the 09 has 3.31s), then this afternoon, the 06 stalled 5 times, rpm surging from 3~400 up to 2000 when it DONT stall- no bottom end, feels like a 4 cylinder until RPM gets up over 2500, then maybe about half normal...
gas is a month old, still 1/4 tank, the first 3/4 ran fine so dont think bad gas (unless someone peed in my tank or something at work)...
seems like a TB issue in my little mind...got home plugged the scanner in, no codes, pulled the inlet off and worked the tb manually to see the feedback% from closed to wide open:
ABS TPS from 16.8% ~ 82.3% seemed pretty linear
REL TPS from 5.8% ~ 70.9% seemed pretty linear
ABS TPS B from 22.3% ~ 90.9% at half throttle, stays at 90.9 to wide open... is this a backup sensor for limp mode that wont let you get full throttle, or is the TPS just shot?
TB moves freely, looks clean, no trouble codes stored...dont recall the pedal sensors tag, but it went pretty close to 0-100% and linear.
thanks for any suggestions
![Smile](https://themustangsource.com/forums/images/smilies/smile.gif)
Tim
EDIT-
did some reading, the non linear on the second channel is normal- I had swapped batteries a couple days ago, never had it above 50- didnt think about the relearning thing- did some more reading, requires 1~3 decelerations under engine braking from 60-40mph to recalibrate misfire sensors, think it mighta just learned a bad map, as I drove normally, but got on the highway for the first time since the battery swap, got off the highway accelerated to about 80 on this nice offramp, shut down and pushed the clutch literally right at works driveway. next drive leaving work it was all messed up- stalled for the first time ever just after starting, 4 more times on the way home, no power, idle all over the place...think the improper deceleration screwed it up, and it just tried to map some bad data...unhooked the battery/shorted the wire terminals for a few, hooked it back up, it was ok, idled fine, power still a little down...let it warm up fully, took it up over 60, coasted back to under 40 in third, its fine- first gear is awesome again!
man was it acting wacky earlier though
Last edited by ford4v429; 4/15/11 at 09:35 PM.
#27
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I remember when mine went screwy. The relearning process is critical to keep these computers happy...
#28
I took my 05 (just bought it used so it's still under warranty) to the dealer the other day with a similar problem, and on cold mornings when I started my car it would make a hissing/grinding noise so the transmission specialist at ford told me I had a blown clutch cylinder and they are replacing it
#29
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I took my 05 (just bought it used so it's still under warranty) to the dealer the other day with a similar problem, and on cold mornings when I started my car it would make a hissing/grinding noise so the transmission specialist at ford told me I had a blown clutch cylinder and they are replacing it
if yours does it again put a voltmeter on the battery and watch while cold cranking, I think 11~12 volts is more the norm even if the battery is down a little
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9/29/15 09:40 AM