Surging, Hesitating, Stalling?
#21
04-23-2012, 07:46 PM
Update:
Well, found out the issue from the p0499 I as having as well as the O2 sensors and the cause of the hesitation and/or surging... somehow my battery overheated (due to my alternator going bad or the battery - says Chrysler techs) and in doing so the battery dripped acid onto my main engine harness (the thing that runs all the sensors to the PCM) as well as getting into the wire from the purge solenoid to being carried by current to the middle of the car and the wire is broken there....
Chrysler estimates it to be @ 6k worth of work.... However, I will get the parts from somewhere else 250 @ for main engine harness (if they still have it) and 280 @ for the body harness, and then find someone else to put it in.... Because really 6k is another car.... Hope this doesn't happen to anyone else!
Well, found out the issue from the p0499 I as having as well as the O2 sensors and the cause of the hesitation and/or surging... somehow my battery overheated (due to my alternator going bad or the battery - says Chrysler techs) and in doing so the battery dripped acid onto my main engine harness (the thing that runs all the sensors to the PCM) as well as getting into the wire from the purge solenoid to being carried by current to the middle of the car and the wire is broken there....
Chrysler estimates it to be @ 6k worth of work.... However, I will get the parts from somewhere else 250 @ for main engine harness (if they still have it) and 280 @ for the body harness, and then find someone else to put it in.... Because really 6k is another car.... Hope this doesn't happen to anyone else!
#23
05-18-2014, 10:14 PM
Good day, or eve to all. M having a similar problem after changing plugs, boots and EGR. There are no codes. All plugs and hoses are good and installed correctly. Checked and rechecked plugs and hoses etc...etc... Anyone with an idea of whats going on? all input will be greatly appreciated. Thanks
#24
05-19-2014, 12:35 PM
05 Pacifica/ Pelum,EGR Valve
Well this is all new to me! After hours of investigating this issue, is there a gasket, some kind of seal between the EGR tube and the Pelum? Getting all kinds of codes that clear except for one on the maps sensor. Looks like there should be something between the two. Any input will be appreciated. Thanks
#25
05-20-2014, 01:41 PM
FINALLY!! After a tuneup, 05 was surging badly. Discovered a seal missing between the plenum(intake) and the EGR tube, was missing. Didnt see it when it was apart. Thus, problem solved. Now to get rid of the codes. Oh and by the way the only place I found one was at a dealership. Go figure....
#26
07-05-2014, 09:25 AM
I have an '07 Pacifica w/ 4.0L w/ similar issues. It starts easily, but idles very rough and runs
like it has only 3 cylinders. The car has 57K miles. Trouble codes were to replace the front
O2 sensors, which I did. Additional trouble code was to replace Intake short runner manifold
valve actuator located on the front part of the intake- but the part is on national back order for over 6 weeks.
So - we disconnected the actuator valve - this helped a little.. It seems there is another manifold actuator on the back of intake as well - should we disconnect this as well...
The car bucks and and gas mileage has decreased as well.
Any ideas......???
like it has only 3 cylinders. The car has 57K miles. Trouble codes were to replace the front
O2 sensors, which I did. Additional trouble code was to replace Intake short runner manifold
valve actuator located on the front part of the intake- but the part is on national back order for over 6 weeks.
So - we disconnected the actuator valve - this helped a little.. It seems there is another manifold actuator on the back of intake as well - should we disconnect this as well...
The car bucks and and gas mileage has decreased as well.
Any ideas......???
#27
07-06-2014, 11:49 AM
I have an '07 Pacifica w/ 4.0L w/ similar issues. It starts easily, but idles very rough and runs
like it has only 3 cylinders. The car has 57K miles. Trouble codes were to replace the front
O2 sensors, which I did. Additional trouble code was to replace Intake short runner manifold
valve actuator located on the front part of the intake- but the part is on national back order for over 6 weeks.
So - we disconnected the actuator valve - this helped a little.. It seems there is another manifold actuator on the back of intake as well - should we disconnect this as well...
The car bucks and and gas mileage has decreased as well.
Any ideas......???
like it has only 3 cylinders. The car has 57K miles. Trouble codes were to replace the front
O2 sensors, which I did. Additional trouble code was to replace Intake short runner manifold
valve actuator located on the front part of the intake- but the part is on national back order for over 6 weeks.
So - we disconnected the actuator valve - this helped a little.. It seems there is another manifold actuator on the back of intake as well - should we disconnect this as well...
The car bucks and and gas mileage has decreased as well.
Any ideas......???
#28
09-15-2014, 10:37 AM
Thanks for all the posts here. My '05 had the characteristic hesitation off the line, then surging when steady at 25MPH, or about 37-38MPH. Finally yesterday it stalled when maneuvering at idle in a parking lot. Grabbed an EGR from O'Reilly for $32 with limited lifetime warranty. It was a bit of a bear to change. I used a combination of short/long extensions and/or deep and shallow sockets to get at the main EGR bolts (2 X 10mm). But it is in, and the car is running great. I had not had any roughness at idle that I noticed, but I can just tell overall it is running better and smoother. Prior to the EGR I had thoroughly cleaned the throttle body and idle air control seeking to solve the issue.
#29
11-23-2014, 07:36 AM
Solution to the loss of throttle
The Chrysler computers need a signal from the front O2 sensor to run correctly. What is happening is the O2 sensor is not putting out a signal until it is warmed. This happens after a few minutes of driving but until a correct signal is sent out by the O2 sensor, the PCM (engine computer) is on its own deciding how much fuel to inject into the engine based on your throttle position and water temperature. It has a special program to do that; it is called open loop. What is happening is the computer is going into closed loop and expecting a signal from the O2 sensor. Because of emission standards PCM’s go into closed loop as quickly as possible. To get the O2 sensor sending out a signal quickly, so it is working by the time the PCM goes into closed loop, engineers have added a heating circuit to the O2 sensor. The sensor must be above 600 degrees to output a signal and this is where the intermittent problem starts to happen. You can let the car idle in the driveway for half an hour and 90 seconds into your drive you lose your throttle. If it is the O2 heater circuit causing the problem, slide the shifter into neutral and push the throttle down. Eventually the engine RPM’s will raise (maybe 5 seconds; seems like forever) and then hold them at 2000rpm for 20 seconds. This will heat the sensor and the throttle will work correctly. If you stop at the store, or wait too long in traffic, you will need to do it again. If you notice a little hesitation the O2 sensor is too cold to work again.
There are 2 reasons for this problem.
One is your O2 heating element in the sensor is bad. To check it unplug the sensor and do an ohm reading across the 2 black wires. It should read 5 ohms. If not replace it.
Second problem; your PCM is not sending out 5 volts to the heater to heat it up. This could be a bad PCM or bad wiring. Checking the wiring harness from the PCM to the O2 sensor one will be ground and one should have 5 volts. The problem with checking it with the O2 sensor unplugged is that there is no load on the PCM and it could still read 5 volts without a load and zero with a load. Plug the sensor back in and check the voltage at the PCM. The factory manual says the heater voltage is supplied to the O2 sensor bank 1 sensor 1 through pin 18 (Black/Orange plug) C2 PCM. It is the second plug up from the bottom and has an orange strip on it. The wire is a brown wire with a tan strip. You have to pull the hood, that covers the back of the plug, off and insert a thin wire into the back of the PCM plug reaching in as far as you can. This is not as easy as it sounds so I recommend unplugging the plug and check using an ohm meter to make sure your wire has contacted the pin. Before you reinsert the plug back into the PCM check the continuity of the brown wire with tan strip to the O2 sensor plug. If the wire is good plug the plug back into the PCM. Start the car and check for 5 volts. If there is no voltage on this pin the manual say replace the PCM unit.
I wanted to make sure the PCM was causing the problem before I spent a lot of money on a new one. All you need to do is supply 5 volts to the heater so I bought a 25 watt DC/DC 12V/24V step down to 5V on Ebay for about $15 including shipping. (I think you could get by with just a 5 watt) I cut just the positive black heater wire about 8” from the sensor and connected the 5 volt wire from the step down power supply. The other 3 wires are still in place. Use an ohm meter to find which black wire is the ground and the other black wire will be the power. O2 sensors have 4 wires 1 blue, 1 white (O2 sensor voltage) and 2 black wires (power for the heater). We have not had any more problems with the throttle so why spend the money on a new PCM. Fixing it this way will keep an “Check Engine” light on all the time. I’ve thought about adding a resister to the dangling heater wire under the car but my wife has become so use to warning light on the dash (it took me a year to figure this all out) that I didn’t go to the trouble.
Before adding a different power supply make sure you remove and clean your ground wires. They are located under the battery box up front. There are 3 of them. I added an extra ground wire from the negative post to the body grounds. These cars use 5 volt for sensors and any grounding problems will cause sensor problems. A sensor problem causes the body/engine computers to do strange things.
For those who claim this is an EGR problem I have to disagree. If you have rough idle, misses on acceleration, and hesitation then EGR is your problem. Those of us who have problems with a loss of throttle, sometimes, will know exactly what I’m talking about. It is like your car is ignoring you! This is an O2 sensor problem.
What we don’t realize is that today’s cars are accelerated by computers and not us. We request to the computer to go faster by pushing on the gas pedal. The gas pedal opens up the air to the engine and by way of a Throttle Position Sensor tells the computer how fast you want to go. The computer then pulses the injectors to reach the RPM’s needed. The PCM then checks with the O2 sensor to see if there is too much or too little gasoline going into the engine. It then adjusts the fuel injector pulses to get maximum air/fuel ratio. When the O2 sensor is not outputting the correct voltage, when the PCM is in close loop, it understands the voltage to say “Too Rich; Cut back Fuel” and the short term fuel trim bank will pull back. My “Short Term Fuel Trim Bank” was at a -30% when I would lose my throttle.
I hope this helps,
steve
The Chrysler computers need a signal from the front O2 sensor to run correctly. What is happening is the O2 sensor is not putting out a signal until it is warmed. This happens after a few minutes of driving but until a correct signal is sent out by the O2 sensor, the PCM (engine computer) is on its own deciding how much fuel to inject into the engine based on your throttle position and water temperature. It has a special program to do that; it is called open loop. What is happening is the computer is going into closed loop and expecting a signal from the O2 sensor. Because of emission standards PCM’s go into closed loop as quickly as possible. To get the O2 sensor sending out a signal quickly, so it is working by the time the PCM goes into closed loop, engineers have added a heating circuit to the O2 sensor. The sensor must be above 600 degrees to output a signal and this is where the intermittent problem starts to happen. You can let the car idle in the driveway for half an hour and 90 seconds into your drive you lose your throttle. If it is the O2 heater circuit causing the problem, slide the shifter into neutral and push the throttle down. Eventually the engine RPM’s will raise (maybe 5 seconds; seems like forever) and then hold them at 2000rpm for 20 seconds. This will heat the sensor and the throttle will work correctly. If you stop at the store, or wait too long in traffic, you will need to do it again. If you notice a little hesitation the O2 sensor is too cold to work again.
There are 2 reasons for this problem.
One is your O2 heating element in the sensor is bad. To check it unplug the sensor and do an ohm reading across the 2 black wires. It should read 5 ohms. If not replace it.
Second problem; your PCM is not sending out 5 volts to the heater to heat it up. This could be a bad PCM or bad wiring. Checking the wiring harness from the PCM to the O2 sensor one will be ground and one should have 5 volts. The problem with checking it with the O2 sensor unplugged is that there is no load on the PCM and it could still read 5 volts without a load and zero with a load. Plug the sensor back in and check the voltage at the PCM. The factory manual says the heater voltage is supplied to the O2 sensor bank 1 sensor 1 through pin 18 (Black/Orange plug) C2 PCM. It is the second plug up from the bottom and has an orange strip on it. The wire is a brown wire with a tan strip. You have to pull the hood, that covers the back of the plug, off and insert a thin wire into the back of the PCM plug reaching in as far as you can. This is not as easy as it sounds so I recommend unplugging the plug and check using an ohm meter to make sure your wire has contacted the pin. Before you reinsert the plug back into the PCM check the continuity of the brown wire with tan strip to the O2 sensor plug. If the wire is good plug the plug back into the PCM. Start the car and check for 5 volts. If there is no voltage on this pin the manual say replace the PCM unit.
I wanted to make sure the PCM was causing the problem before I spent a lot of money on a new one. All you need to do is supply 5 volts to the heater so I bought a 25 watt DC/DC 12V/24V step down to 5V on Ebay for about $15 including shipping. (I think you could get by with just a 5 watt) I cut just the positive black heater wire about 8” from the sensor and connected the 5 volt wire from the step down power supply. The other 3 wires are still in place. Use an ohm meter to find which black wire is the ground and the other black wire will be the power. O2 sensors have 4 wires 1 blue, 1 white (O2 sensor voltage) and 2 black wires (power for the heater). We have not had any more problems with the throttle so why spend the money on a new PCM. Fixing it this way will keep an “Check Engine” light on all the time. I’ve thought about adding a resister to the dangling heater wire under the car but my wife has become so use to warning light on the dash (it took me a year to figure this all out) that I didn’t go to the trouble.
Before adding a different power supply make sure you remove and clean your ground wires. They are located under the battery box up front. There are 3 of them. I added an extra ground wire from the negative post to the body grounds. These cars use 5 volt for sensors and any grounding problems will cause sensor problems. A sensor problem causes the body/engine computers to do strange things.
For those who claim this is an EGR problem I have to disagree. If you have rough idle, misses on acceleration, and hesitation then EGR is your problem. Those of us who have problems with a loss of throttle, sometimes, will know exactly what I’m talking about. It is like your car is ignoring you! This is an O2 sensor problem.
What we don’t realize is that today’s cars are accelerated by computers and not us. We request to the computer to go faster by pushing on the gas pedal. The gas pedal opens up the air to the engine and by way of a Throttle Position Sensor tells the computer how fast you want to go. The computer then pulses the injectors to reach the RPM’s needed. The PCM then checks with the O2 sensor to see if there is too much or too little gasoline going into the engine. It then adjusts the fuel injector pulses to get maximum air/fuel ratio. When the O2 sensor is not outputting the correct voltage, when the PCM is in close loop, it understands the voltage to say “Too Rich; Cut back Fuel” and the short term fuel trim bank will pull back. My “Short Term Fuel Trim Bank” was at a -30% when I would lose my throttle.
I hope this helps,
steve
I am going to follow your suggestions to a T. Cept I will have my son doing the work since I am unable. I will be out there with a copy of this post and we will go over everything step by step starting with faulty grounds. Have already replaced EGR and MAP sensors.
Thank you so much for this post. Now I can be happy driving my 05 Pacifica instead of scared.
#30
01-01-2016, 02:01 PM
Eureka!!!! Problems fixed
Eureka!!!! Your problems are solved.. If your having shuttering problems, problems with your EGR, idle air control, throttle positioning sensor, car not turning over, car acting erratically or dying out and even transmission issues such as going in limp mode not switching gears... It is in 2 places the wire harness!!!!
1) Under the tire well above the dog bone for suspension is a Negative or ground cable bolted to the transmission this sometimes comes loose and will prevent your car from starting or even turning over.. There is also a harness that passes over this bolt which will rub out on the back side in time.. This will cause problems in the egr, i.a.c., t.p.s and Ats.... Fix the wire fix the problem
2) if you open your hood under your battery not directly but down low youll see your solenoid packs and other transmission sensors follow these to the thicker wire harness down to wear it almost touches the frame and meets other wire harnesses... The back side of this "crossroad" rubs up against some kind of flange on the transmission with bolt holes in it.. This is the problem with transmission issues in the 2004 Chrysler Pacifica 3.5l.. Fix the wire fix the problem!!! I spent alot of money on parts to figure out this simple easy cheap fix.. Make sure to reinforce protection in the back of theose wires during fix.. Hope i saved you some time and money!
1) Under the tire well above the dog bone for suspension is a Negative or ground cable bolted to the transmission this sometimes comes loose and will prevent your car from starting or even turning over.. There is also a harness that passes over this bolt which will rub out on the back side in time.. This will cause problems in the egr, i.a.c., t.p.s and Ats.... Fix the wire fix the problem
2) if you open your hood under your battery not directly but down low youll see your solenoid packs and other transmission sensors follow these to the thicker wire harness down to wear it almost touches the frame and meets other wire harnesses... The back side of this "crossroad" rubs up against some kind of flange on the transmission with bolt holes in it.. This is the problem with transmission issues in the 2004 Chrysler Pacifica 3.5l.. Fix the wire fix the problem!!! I spent alot of money on parts to figure out this simple easy cheap fix.. Make sure to reinforce protection in the back of theose wires during fix.. Hope i saved you some time and money!