Truck occasionally dies when stopping
Thread Starter
|
Amateur
Joined: Mar 2009
Posts: 36
Likes: 0
Yes I reset the PCM after every change I made.
My best guess is that my transmission fluid was super low. I've been keeping an eye on it for a few months.
I'm 99% sure that it was because my transmission was getting stuck while downshifting (heading to a stop) or shifting in reverse. After the lucus stop leak I haven't had any issues since.
The MAP sensor is more for a MPG test as it really doesn't apply much to it stalling out. Only gain 1.5MPG for switching to a new sensor so not quite worth it.
My best guess is that my transmission fluid was super low. I've been keeping an eye on it for a few months.
I'm 99% sure that it was because my transmission was getting stuck while downshifting (heading to a stop) or shifting in reverse. After the lucus stop leak I haven't had any issues since.
The MAP sensor is more for a MPG test as it really doesn't apply much to it stalling out. Only gain 1.5MPG for switching to a new sensor so not quite worth it.
Amateur
Joined: Oct 2017
Posts: 25
Likes: 1
Same
2001 Dodge Dakota 4.7 V8 QUAD Cab *Updated 5/25/2011*
This started happening about a 6 months ago where the engine will occasionally die when stopping at a red light or at a stop sign. Sometimes it feels like stopping on an incline causes it to die more but it does die even on flat ground.
Here are my symptoms:
Here's what I've done to try and fix the issue to no avail:
What to do next?
Dakota Idle Drops when Stopping - YouTube
Dakota Idle Drops when Stopping #2 - YouTube
In these videos I jam the RPM decently high, then come to a complete stop suddenly. Where you see the drop is actually when the car has that snap back effect when stopping quickly. Hopefully this insight will give new ideas to solve this issue. These videos are AFTER replacing the IAC and TPS.
What does everyone think? Has anybody experience this issue before? Which fix should I try first? Also any input on my bad MPG?
*Update 5/25/2011*
Replaced the IAC sensor, there is def. improvement however the idle does still dip when going in reverse or stopping.
*Update 5/31/2011*
Replaced the TPS. Sadly zero improvement.
*Update 2/01/2013*
Ran the 3M fuel system cleaner through the throttle body and fuel tank. Also cleaned the throttle body manually.
Added lucus transmission repair fluid fix.
No improvement
*Update 2/14/2013*
Ordered Vehicle Speed Sensor, MAP Sensor (this is for crappy MPG issue)
*Update 2/25/2013*
Installed MAP sensor and did an oil change, refill transmission fluid, radiator fluids and power steering fluids. Put some stop leak products for radiator and power steering.
*Update 3/22/2013*
Symptoms vanished? My guess is that it has to do with the transmission fluid level since after the Lucus treatment + transmission refill I haven't had any issues. I did put in the MAP sensor at the same time but I really don't think that could be related. Either I have a feeling the transmission is the weak point of my truck and will start saving in case it fails on me. Currently I haven't had any issues or symptoms for about a month.
This started happening about a 6 months ago where the engine will occasionally die when stopping at a red light or at a stop sign. Sometimes it feels like stopping on an incline causes it to die more but it does die even on flat ground.
Here are my symptoms:
- Dies while stopping
- RPM tries to fight but ends up dead
- RPM struggles when AC is on
- Truck is shifting hard both up and down *updated 7/18/2011
- RPM struggles a tiny bit when using power steering
- Truck dies sometimes when going from drive to reverse
- Truck starts back up easily every time
- MPG on my truck seems pretty bad at 12MPG
- RPM idles at a tad bit above 500.
- Battery is less than 6 months old. *updated 5/25/2011
Here's what I've done to try and fix the issue to no avail:
- Replaced Spark Plugs
- Replaced Spark Wires
- Cleared air filter
- Reset truck computer (unplug battery)
- Put Seafoam in gas tank *updated 5/11/2011
- Replaced IAC *updated 5/25/2011
- Replace the TPS sensor *updated 5/31/2011
- Ran 3M fuel system cleaner *updated 2/1/2013
- Clean throttle body *updated 2/1/2013
- Added Lucas transmission fluid fix *updated 2/1/2013
- Tested replacement TPS voltage 3.37 closed 3.89 open. Seems good. *updated 2/15/2013
- Transmission refill + oil change + MAP sensor install + radiator refill *updated 2/25/2013
What to do next?
- Go to dealer and get new PCM firmware
- Replace VSS
- Eat a shotgun
Dakota Idle Drops when Stopping - YouTube
Dakota Idle Drops when Stopping #2 - YouTube
In these videos I jam the RPM decently high, then come to a complete stop suddenly. Where you see the drop is actually when the car has that snap back effect when stopping quickly. Hopefully this insight will give new ideas to solve this issue. These videos are AFTER replacing the IAC and TPS.
What does everyone think? Has anybody experience this issue before? Which fix should I try first? Also any input on my bad MPG?
*Update 5/25/2011*
Replaced the IAC sensor, there is def. improvement however the idle does still dip when going in reverse or stopping.
*Update 5/31/2011*
Replaced the TPS. Sadly zero improvement.
*Update 2/01/2013*
Ran the 3M fuel system cleaner through the throttle body and fuel tank. Also cleaned the throttle body manually.
Added lucus transmission repair fluid fix.
No improvement
*Update 2/14/2013*
Ordered Vehicle Speed Sensor, MAP Sensor (this is for crappy MPG issue)
*Update 2/25/2013*
Installed MAP sensor and did an oil change, refill transmission fluid, radiator fluids and power steering fluids. Put some stop leak products for radiator and power steering.
*Update 3/22/2013*
Symptoms vanished? My guess is that it has to do with the transmission fluid level since after the Lucus treatment + transmission refill I haven't had any issues. I did put in the MAP sensor at the same time but I really don't think that could be related. Either I have a feeling the transmission is the weak point of my truck and will start saving in case it fails on me. Currently I haven't had any issues or symptoms for about a month.
Registered User
Joined: Jul 2011
Posts: 12
Likes: 0
Truck occasionally dies when stopping
Seems like most of the replaced parts was in 2013..that's about 5 years ago.
"Tested replacement TPS voltage 3.37 closed 3.89 open. Seems good. *updated 2/15/2013 "
THAT IS ONLY ABOUT HALF A VOLT DIFFERENTIAN BETWEEN CLOSED AND OPEN THROTTLE!
IMO, the TPS is suspect as it has a LOT TO DO with RPM idle.
Did it idle properly after the throttle position sensor was replaced?
I had a similar problem with my 98 dakota (5.0L)...it would stall
at stoplights when idling. I replaced it with an aftermarker TPS sensor
and made sure it was installed correctly as there is ONLY one way
to install those. Same symptom. I was ready to go to a mopar dealer
but the online parts place sent me a replacement TPS, which cleared
the problem.
Maybe you need to investigate that a bit more?
The ECM controls the idle rpm. IF the TPS sensor is giving it erratic voltage swings,
the idle will be erratic. The ECM WILL SHUT DOWN the ignition and fuel injector control
voltage if the idle drops down too much below 500rpm.
The TPS sensor tells it if the throttle plate is moving from the CLOSED
position to fully open position and is very SENSITIVE as it's a 5v.0 dc
sensor, so there is only about a 3 volt differential between closed and open
throttle. Your TPS sensor doesn''t seem to be producing the proper voltage.
"Tested replacement TPS voltage 3.37 closed 3.89 open. Seems good. *updated 2/15/2013 "
THAT IS ONLY ABOUT HALF A VOLT DIFFERENTIAN BETWEEN CLOSED AND OPEN THROTTLE!
IMO, the TPS is suspect as it has a LOT TO DO with RPM idle.
Did it idle properly after the throttle position sensor was replaced?
I had a similar problem with my 98 dakota (5.0L)...it would stall
at stoplights when idling. I replaced it with an aftermarker TPS sensor
and made sure it was installed correctly as there is ONLY one way
to install those. Same symptom. I was ready to go to a mopar dealer
but the online parts place sent me a replacement TPS, which cleared
the problem.
Maybe you need to investigate that a bit more?
The ECM controls the idle rpm. IF the TPS sensor is giving it erratic voltage swings,
the idle will be erratic. The ECM WILL SHUT DOWN the ignition and fuel injector control
voltage if the idle drops down too much below 500rpm.
The TPS sensor tells it if the throttle plate is moving from the CLOSED
position to fully open position and is very SENSITIVE as it's a 5v.0 dc
sensor, so there is only about a 3 volt differential between closed and open
throttle. Your TPS sensor doesn''t seem to be producing the proper voltage.
Amateur
Joined: Oct 2017
Posts: 25
Likes: 1
Seems like most of the replaced parts was in 2013..that's about 5 years ago.
"Tested replacement TPS voltage 3.37 closed 3.89 open. Seems good. *updated 2/15/2013 "
THAT IS ONLY ABOUT HALF A VOLT DIFFERENTIAN BETWEEN CLOSED AND OPEN THROTTLE!
IMO, the TPS is suspect as it has a LOT TO DO with RPM idle.
Did it idle properly after the throttle position sensor was replaced?
I had a similar problem with my 98 dakota (5.0L)...it would stall
at stoplights when idling. I replaced it with an aftermarker TPS sensor
and made sure it was installed correctly as there is ONLY one way
to install those. Same symptom. I was ready to go to a mopar dealer
but the online parts place sent me a replacement TPS, which cleared
the problem.
Maybe you need to investigate that a bit more?
The ECM controls the idle rpm. IF the TPS sensor is giving it erratic voltage swings,
the idle will be erratic. The ECM WILL SHUT DOWN the ignition and fuel injector control
voltage if the idle drops down too much below 500rpm.
The TPS sensor tells it if the throttle plate is moving from the CLOSED
position to fully open position and is very SENSITIVE as it's a 5v.0 dc
sensor, so there is only about a 3 volt differential between closed and open
throttle. Your TPS sensor doesn''t seem to be producing the proper voltage.
"Tested replacement TPS voltage 3.37 closed 3.89 open. Seems good. *updated 2/15/2013 "
THAT IS ONLY ABOUT HALF A VOLT DIFFERENTIAN BETWEEN CLOSED AND OPEN THROTTLE!
IMO, the TPS is suspect as it has a LOT TO DO with RPM idle.
Did it idle properly after the throttle position sensor was replaced?
I had a similar problem with my 98 dakota (5.0L)...it would stall
at stoplights when idling. I replaced it with an aftermarker TPS sensor
and made sure it was installed correctly as there is ONLY one way
to install those. Same symptom. I was ready to go to a mopar dealer
but the online parts place sent me a replacement TPS, which cleared
the problem.
Maybe you need to investigate that a bit more?
The ECM controls the idle rpm. IF the TPS sensor is giving it erratic voltage swings,
the idle will be erratic. The ECM WILL SHUT DOWN the ignition and fuel injector control
voltage if the idle drops down too much below 500rpm.
The TPS sensor tells it if the throttle plate is moving from the CLOSED
position to fully open position and is very SENSITIVE as it's a 5v.0 dc
sensor, so there is only about a 3 volt differential between closed and open
throttle. Your TPS sensor doesn''t seem to be producing the proper voltage.
Registered User
Joined: Jul 2011
Posts: 12
Likes: 0
If you are already on the 3rd TPS sensor and the idle is erratic, you need to use a DVM to check
the voltage at the sensor wires and see if it is nearly 0 volts at closed throttle and around 2.5 to
3.0 volts fully open. The voltage increase is gradual as you open the throttle plate by hand from
fully closed position to the fully open position.
You can do this with the engine not running but with the key on. If you are not
getting at least 2.5volt differential between fully closed and fully open throttle, the sensor IS or
has gone defective. Best to get a genuine Mopar TPS and be assured at least that it will work
if it is installed properly. Check the TPS voltage swing before starting the truck.
the voltage at the sensor wires and see if it is nearly 0 volts at closed throttle and around 2.5 to
3.0 volts fully open. The voltage increase is gradual as you open the throttle plate by hand from
fully closed position to the fully open position.
You can do this with the engine not running but with the key on. If you are not
getting at least 2.5volt differential between fully closed and fully open throttle, the sensor IS or
has gone defective. Best to get a genuine Mopar TPS and be assured at least that it will work
if it is installed properly. Check the TPS voltage swing before starting the truck.
Amateur
Joined: Oct 2017
Posts: 25
Likes: 1
If you are already on the 3rd TPS sensor and the idle is erratic, you need to use a DVM to check
the voltage at the sensor wires and see if it is nearly 0 volts at closed throttle and around 2.5 to
3.0 volts fully open. The voltage increase is gradual as you open the throttle plate by hand from
fully closed position to the fully open position.
You can do this with the engine not running but with the key on. If you are not
getting at least 2.5volt differential between fully closed and fully open throttle, the sensor IS or
has gone defective. Best to get a genuine Mopar TPS and be assured at least that it will work
if it is installed properly. Check the TPS voltage swing before starting the truck.
the voltage at the sensor wires and see if it is nearly 0 volts at closed throttle and around 2.5 to
3.0 volts fully open. The voltage increase is gradual as you open the throttle plate by hand from
fully closed position to the fully open position.
You can do this with the engine not running but with the key on. If you are not
getting at least 2.5volt differential between fully closed and fully open throttle, the sensor IS or
has gone defective. Best to get a genuine Mopar TPS and be assured at least that it will work
if it is installed properly. Check the TPS voltage swing before starting the truck.
Registered User
Joined: Jul 2011
Posts: 12
Likes: 0
The TPS sensor is not exacty the same as a carbon resistor potentiometer, although for all intensive purposes, it acts like one.
The TPS sensor is a solid state sensor (Hall Effect), similar to the Crankshaft/camshaft sensors on the engine. The ECM can only
accept sensor input voltages in the 5.0vdc range. (Typically 0.5v to 4.5 volts depending on the throttle position).
ECM supplies the 5.0volt to one wire on the sensor ( and you can read the o/p voltage on the middle wire..red, I believe) and reads the o/p of the TPS sensor on the other wire of the 3 wire plug.
Ground is common from the screw mounts. Engine ground can be used for the test.
The ECM takes the signal (instintanious DC voltage) from the sensor depending on where the throttle shaft butterfly position and PROCESSES that signal and compares it to its internal memory map to determine: fuel perameters and ignition perameteres, along with other sensors, CRank position, Cam position, MAP, MASS, and any other sensors that produce signals to make the engine run at a certain rpm based on throttle position.
The TPS is one of the most criticaL. The Hall effect sensor inside (read Hall effect on Wikipedia for more information) is notorious
for going bad or even erratic, depending on the aftermarket brand used.
Testing the TPS sensor:
The TPS sensor is a solid state sensor (Hall Effect), similar to the Crankshaft/camshaft sensors on the engine. The ECM can only
accept sensor input voltages in the 5.0vdc range. (Typically 0.5v to 4.5 volts depending on the throttle position).
ECM supplies the 5.0volt to one wire on the sensor ( and you can read the o/p voltage on the middle wire..red, I believe) and reads the o/p of the TPS sensor on the other wire of the 3 wire plug.
Ground is common from the screw mounts. Engine ground can be used for the test.
The ECM takes the signal (instintanious DC voltage) from the sensor depending on where the throttle shaft butterfly position and PROCESSES that signal and compares it to its internal memory map to determine: fuel perameters and ignition perameteres, along with other sensors, CRank position, Cam position, MAP, MASS, and any other sensors that produce signals to make the engine run at a certain rpm based on throttle position.
The TPS is one of the most criticaL. The Hall effect sensor inside (read Hall effect on Wikipedia for more information) is notorious
for going bad or even erratic, depending on the aftermarket brand used.
Testing the TPS sensor:
Last edited by carverman; Feb 23, 2018 at 10:14 AM.
Amateur
Joined: Oct 2017
Posts: 25
Likes: 1
The TPS sensor is not exacty the same as a carbon resistor potentiometer, although for all intensive purposes, it acts like one.
The TPS sensor is a solid state sensor (Hall Effect), similar to the Crankshaft/camshaft sensors on the engine. The ECM can only
accept sensor input voltages in the 5.0vdc range. (Typically 0.5v to 4.5 volts depending on the throttle position).
ECM supplies the 5.0volt to one wire on the sensor ( and you can read the o/p voltage on the middle wire..red, I believe) and reads the o/p of the TPS sensor on the other wire of the 3 wire plug.
Ground is common from the screw mounts. Engine ground can be used for the test.
The ECM takes the signal (instintanious DC voltage) from the sensor depending on where the throttle shaft butterfly position and PROCESSES that signal and compares it to its internal memory map to determine: fuel perameters and ignition perameteres, along with other sensors, CRank position, Cam position, MAP, MASS, and any other sensors that produce signals to make the engine run at a certain rpm based on throttle position.
The TPS is one of the most criticaL. The Hall effect sensor inside (read Hall effect on Wikipedia for more information) is notorious
for going bad or even erratic, depending on the aftermarket brand used.
Testing the TPS sensor:
https://www.youtube.com/watch?v=RdArBRZdr7A
The TPS sensor is a solid state sensor (Hall Effect), similar to the Crankshaft/camshaft sensors on the engine. The ECM can only
accept sensor input voltages in the 5.0vdc range. (Typically 0.5v to 4.5 volts depending on the throttle position).
ECM supplies the 5.0volt to one wire on the sensor ( and you can read the o/p voltage on the middle wire..red, I believe) and reads the o/p of the TPS sensor on the other wire of the 3 wire plug.
Ground is common from the screw mounts. Engine ground can be used for the test.
The ECM takes the signal (instintanious DC voltage) from the sensor depending on where the throttle shaft butterfly position and PROCESSES that signal and compares it to its internal memory map to determine: fuel perameters and ignition perameteres, along with other sensors, CRank position, Cam position, MAP, MASS, and any other sensors that produce signals to make the engine run at a certain rpm based on throttle position.
The TPS is one of the most criticaL. The Hall effect sensor inside (read Hall effect on Wikipedia for more information) is notorious
for going bad or even erratic, depending on the aftermarket brand used.
Testing the TPS sensor:
https://www.youtube.com/watch?v=RdArBRZdr7A
I am not familiar with all the types of TPS sensors on all makes and models of vehicles. The purpose of the TPS is to communicate the position of the throttle plate to the PCM. If the signal, be it variations in voltage, or, binary pulses, (possible "other" version of sensor), provides the same function.