Cel code p0129
I'm having an issue with my 2004 dodge ram 2500 5.7 hemi. I'm getting the cel code p0129. This is causing the truck to rough idle at times and stall when turning or coming to a stop. When I get the code and the check engine light comes on the etc light also comes on. The truck drives and idles fine other than it won't shift into 4th when the etc light is on. I've already changes the throttle body the map sensor the iat sensor the crankshaft position sensor and the pcv valve. I'm at a loss on what is causing the problem and what the fix is. Any help would be greatly apprecia
Experienced mechanics share their insights in answering this question :
Well you replaced all the parts associated with your code. You need a voltage meter to measure the voltage at the sensor. There should be a 5-volt signal and a ground on the outer wires on the sensor. If you do not have 5 volts, you likely have a wiring problem or a blown engine computer.
Use a digital voltmeter and verify voltage at the outer pins. The middle wire should read voltage as well. The most common problems include the sensor, wiring, or computer. Replacing the computer requires programming. If you still need assistance with this, a professional technician from YourMechanic can come visit your car’s location to diagnose the Check Engine Light for you. By looking at the car in person, they’ll be able to pinpoint exactly what the car needs and suggest the correct repairs.
How to Identify and Fix Common car Problems ?
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What does OBD-II fault code P0129 mean? The engine control module (PCM) uses a Pressure sensor in the intake to determine airflow through the engine. If the PCM detects the signal is too low, it will set code P0129.
There is no one fix for a P0129 code. BARO and MAP sensor designs may vary significantly per vehicle manufacturer. If you plan on fixing the underlying issue on your own, we recommend consulting a vehicle-specific repair manual.
This code indicates the voltage from the MAP sensor to the PCM is greater than 4.9 volts or less than 2.28 volts. When this occurs, there is usually a short to ground or a short to power.
Common signs include poor engine performance, like sluggish acceleration, lack of power, and misfires, as well as the Check Engine Light turning on.
Where are these Barometric Pressure Sensors located? Standalone BARO sensors are typically mounted on the firewall or the inside fender skirt. Late model BARO sensors are incorporated into the MAP sensor, and may be mounted on the intake manifold.
Pressure sensor typically “die” in the field because of mechanical damage, electrical overload (like lightning or misconnection during inspections/repair work) or, most commonly, damage by over-pressure, pressure spikes or ingress of moisture/chemicals into the product.
Your vehicle will not only run less efficiently without the readings from the MAP sensor, but its engine and catalytic converter may also wear out faster. To keep your ride running smoothly for as long as possible, you should avoid driving with a bad MAP sensor unless it`s an emergency.
Parts cost on average $67.02 – $81.92, and services cost $106.20 – $129.80. This repair takes on average 0.90h – 1.10h for a mechanic to complete. A certified mechanic can help you replace the barometric sensor, which monitors the amount of air pumped into your vehicle`s engine.
Moisture ingress is one of the most common causes of pressure sensor failure.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Check Engine Light is on – codes P0313, P0299, P0304
ANSWER : Hi there. Based on what you’ve described, this could be a combination of faults between 2 or more things; however, I don’t believe the coils and spark plugs are at fault. One of the codes is set during a low fuel misfire (lean condition), one is specifying a misfire on cylinder 4, and one is a turbo related code; all based on a generic code investigation.
The make and model of the vehicle helps, but is not necessary at the moment. When a low fuel pressure misfire is set, there is a lean condition that has been detected by the sensors and one of the codes is telling us in which cylinder this is occurring. A possibility is a restricted fuel injector, loose injector harness, poor pin fit in the wire harness, and an air leak near that cylinder’s port in the intake manifold.
I’m leaning more towards a leak or crack somewhere creating an air leak since we also have a turbo related code stored and an intermittent rough start when cold. I strongly suggest having a qualified technician perform an inspection to determine the root cause. YourMechanic has several available technicians that can assist you with a Check Engine Light inspection and determine exactly what is giving rise to codes P0313, P0299, and P0304.
Can i retrieve CEL code from car … forgot what code it hade in my car .. put headgasket sealer and i erase the code ..
ANSWER : Once a trouble code is erased, it cannot be retrieved. The engine controller does not have a "recycle bin" like they have on Windows. If the car still has a problem, the code will come back up after some driving. However, the controller will not turn on the CEL until it has seen the malfunction on two separate "trips." A "trip" is a driving cycle where the car is started cold, driven until it is fully warm and through a certain number of accelerations, and shut down. So you might not see the CEL for a couple of days. As for the "head gasket sealer," I wouldn’t hold out too much hope of that solving a problem. At the very best it might put off the symptoms for a short while. If you need help interpreting codes that come up, or solving a head gasket issue, contact Your Mechanic. They can send a technician to your home or office to read the codes on your car and help you decide what to do.
One month ago cel came on I changed spark plugs to after market plugs. One month later cel on again with misfire code.
ANSWER : If the spark plugs hadn’t been changed until 130k, it was time for the to be replaced anyway. This is probably why the dealer went with that repair as worn spark plugs can cause misfires. Ignition coils are another part that may fail and cause misfires when they malfunction. A compression test and cylinder leak-down test will show if there is a problem with the valves. You can try having the coils replaced and the valves adjusted by the dealer. Consider hiring an experienced technician like one from YourMechanic who can come out and conduct the same tests as the dealer could and determine the cause for your check engine light.
I have a Code P0601 on the PCM. I replaced the PCM, and now I have a code P0118, code P0123, and code P0193.
ANSWER : Hi there, the short answer to your question is no . A PCM with a P0601 (which is a memory module error in the PCM) cannot reliably retrieve codes for the codes you list (P0118 – coolant temp sensor, P0123 – throttle position sensor, P0193 – fuel rail pressure sensor.
Most likely, the P0601 prevents the PCM from getting any codes from the engine sensors. The memory module error may cause in data corruption for collected sensor values, lose of data over multiple sampling periods, or failure of the data collection to work at all. Replacing the PCM was a necessary expense.
If you need assistance with the "new" codes, I would recommend having a Check Engine Light inspection completed by a mobile, professional mechanic, such as one from YourMechanic, to diagnose the new error codes and get an accurate assessment of the repairs needed.
It threw a code 21 , throttle position sensor bad code. i replaced it and the code went away but i still have no spark.
ANSWER : Hello and thank you for contacting YourMechanic. The problems that you are encountering with your vehicle, could be caused by the harness to the Throttle Position Sensor (TPS) or the computer itself.
Check the harness to the TPS for any debris or any corrosion. Hook up a paperclip to the harness and turn on the key. Use a multimeter and check for voltage at the pins of the harness. Make sure that the ground on the sensor is grounded and has no resistance. If you find that the harness is having too much resistance, then I recommend having the main engine harness replaced. If you have replaced the harness and still have the same problems, then the computer will need to be flashed or replaced.
I recommend having a professional, like one from YourMechanic, come to your home to diagnose your car’s no start condition before replacing any parts.
2005 Cobalt CEL after code repair
ANSWER : Hello. A catalytic converter code can come up for many reasons, usually indicated by the specific trouble code. A catalytic converter code can point to a few different things. Depending on the code, a few common causes could be faulty oxygen sensors, issues with the engine management system, or a faulty catalytic converter.
You may continue to drive the vehicle, however, it will likely cause the issue to worsen over time. If the Check Engine Light starts flashing, I would then stop driving the vehicle, as the computer has detected an issue that could potentially cause damage to the vehicle’s emissions components.
As the possibilities will vary depending on the specific trouble code, I would recommend having a professional technician, such as one from YourMechanic, visit your location, to diagnose the Check Engine Light and determine if the catalytic converter needs to be replaced.
Service engine warning, MAF code and O2 sensor code, along with check suspension light are turned on
ANSWER : Hello, it sounds like you have quite a few things going on. I am going to do my best to break them down for you.
First if the engine is very loud when idling and the belt has already been replaced, there may be an issue with the tensioner or idler pulley.
Next, the Navigator is known for needing service to the air suspension system as it gets up in miles, the most common causes of these are the air struts themselves have failed, or one of the air lines has a leak.
Lastly, if the O2 sensor and MAF are continually coming back after the sensors have been replaced, the most common cause would be either an exhaust leak or a vacuum leak.
Qualified technicians such as the ones at YourMechanic will be able to diagnose these issues and recommend the best path to repair, starting with a diagnosis of your warning lights.
EGR code, Cylinder 4 misfire code 0304 detected.
ANSWER : Hi there. The Exhaust Gas Recirculation (EGR) valve may be not designed for the emissions requirements for U.S. standards. If the EGR is pulling from cylinder number 4 and after replacing the EGR and the computer detects a misfire, then the EGR is malfunctioning and not responding. When you close off the tube to the EGR and the EGR light comes on and the misfire light goes out, then the EGR is not responding to your emissions system. I recommend replacing the EGR with the OEM specified part for the engine and all of the issues should go away. If you need further assistance with your misfire and EGR, then seek out a professional, such as one from Your Mechanic, to help you.
