ABS comes on under 3 mph and when starting out
I have replaced all 4 speed sensors
both rear hubs ,
right front axle,
ABS controller,
Modulator pump,
No codes come up ,front bearings are good .
I have been reading about the Yaw sensor and the throttle position sensor and see that they are part of the system ..
The idle and speed increase are smooth.
My scanner does not pick up anymore codes now ,they are all cleared with doing the work so far But this problem does not go away .
Any idea what else could cause this ,I cannot find this problem on the net anywhere .
both rear hubs ,
right front axle,
ABS controller,
Modulator pump,
No codes come up ,front bearings are good .
I have been reading about the Yaw sensor and the throttle position sensor and see that they are part of the system ..
The idle and speed increase are smooth.
My scanner does not pick up anymore codes now ,they are all cleared with doing the work so far But this problem does not go away .
Any idea what else could cause this ,I cannot find this problem on the net anywhere .
My car has 160000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hi there. When this occurs I usually install my scan tool to check the inputs from this system. From what you are explaining it sounds like you have replaced many of the sensors. You need to also make sure that all of the tires are exactly the same. If they are then the yaw sensor needs to be checked and the TPS needs to be checked. Most of the time it is caused by the yaw sensor. It can also simply need to be reprogrammed. If you need to have this ABS system checked out, consider YourMechanic, as a certified mechanic can come to you to [diagnose why the ABS light is coming on] https://www.yourmechanic.com/services/abs-light-is-on-inspection
How to Identify and Fix Common car Problems ?
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When the ABS kicks in at low speeds on dry pavement, the usual cause is a weak signal from an ABS speed sensor. It`s normal for the strength (amplitude) of the signal generated by an ABS sensor to gradually diminish as wheel speed decreases.
The ABS light (usually yellow, amber or orange) should come on briefly every time you start your car as part of a system check. If the light stays on, that means something isn`t working and the system has been shut down. With ABS, sensors mounted at each wheel monitor the speed at which the wheels are turning.
It`s Normal For Your ABS Light To Briefly Flash When You Start The Car. Your ABS system conducts a self-check every time you start the engine. Once you start the engine, the ABS light should briefly flash on the dashboard. This is normal, and shows that the ABS system is checking itself as it`s supposed to.
One way to familiarize yourself with the operation of ABS is to test drive the vehicle at a speed above which the ABS activates (usually above 10 mph) in an unobstructed parking lot and apply the brakes firmly.
You won`t feel your ABS kicking in at lower speeds, as it generally starts working only around 25 km/h or more (which is why you won`t activate it when backing up, since you`re usually going slower than that).
Blown Fuse or Stuck Bulb
Sometimes a blown fuse to the ABS can cause the light to come on and stay on. Fuses are easy to blow, so sometimes it`s an easy fix to check.
What if my ABS engages when it shouldn`t? It`s possible for the ABS to engage when it shouldn`t. The most common reason for this is a faulty wheel speed sensor. If a wheel speed senor reads 0 MPH incorrectly while braking, the system will engage and no fault code(s) will be stored.
An errant hammer or wrench blow may deliver damage to a wheel sensor that isn`t immediately apparent, but can cause intermittent problems later. A rusted or damaged ABS pulse wheel may also cause false ABS activation.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Fuel pump engages. Batery good, alternator good volts, jump start helps when wont start. Temp does not matter. Intermittent?
ANSWER : Hello. Thank you for writing in. There are several reasons your vehicle may only start when jump starting. The first and most common is a build up of resistance that is causing you to need a boost of voltage to get the engine started. This may be due to poor battery cables, a bad ground connection, a poor starter solenoid, and a couple of other issues. The first thing you want to do is perform a visual inspection of the starting system. Make sure there is no corrosion build up in the battery cables. You can also check the resistance across these wires and make sure you have a solid connection between components. You then want to make sure the starter solenoid is doing its job. It is responsible for taking the small amount of electricity sent by the ignition and turning it into a huge electrical charge that is strong enough to push over the engine with the help of some gear ratios in its favor. Do some more testing, and stick to the basics before assuming its something seriously complicated.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
Vehicle won’t start, once it’s jump started it only stays running until you turn it off, then it work start again without jumping.
ANSWER : Hi there. There could be two problems here. It is possible that your battery is bad and will not take a charge from your alternator while driving. In that case every time you shut your car off you will not have enough juice to start it again. Inspect your battery – it should have at least 12.5 to 13 volts to start your car, if it doesn’t you will need to replace the battery. The second problem could be that your alternator is bad and not charging your battery, in this case you will need to replace your alternator. Both the battery and the alternator can be tested in your car. If you would like to have the car checked for you, a certified professional from YourMechanic can come to your car’s location to diagnose the starting problem and proceed with repairs.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
Cranks over start than dies
ANSWER : Hi There,
The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher dose of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.
The idle air control valve is a small valve on the engine’s intake system that reads the air intake as it comes into the motor. This is controlled by the car’s ECM which uses this information to make adjustments to the air/fuel ratio depending on various inputs such as outside air temperature, intake air temperature, load and various other things. As you accelerate, your car’s engine is receiving a much higher dose of fuel than when at idle and conversely, when you let off the gas pedal, there is a sudden change in this fuel supply as a result of your foot letting off the pedal. When this happens, the job of the idle air control valve is to bring this deceleration down to a slow and smooth idle rather than suddenly cutting off the fuel supply causing the motor to die. When the idle air control valve is not working properly, this cause a disruption in this process resulting in the engine not being able to idle properly. I would recommend having a professional come to your location to diagnose and inspect your vehicle.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
Engine tapping noise related to short term fuel trim but only on cold start up.
ANSWER : Has a mechanic’s stethoscope been used to track down the specific location of the noise? There are several solenoid valves in the engine bay that do not run all the time and may be pretty loud once they start, such as an evaporative emissions purge valve and the like. The high fuel trims on one bank sound like you may have a problem on one side with a vacuum leak. A positive trim means air is being added and the computer is trying to add fuel to compensate.
I recommend having an experienced technician, such as one from YourMechanic, come to your location to determine why the engine is making a noise and suggest the proper repair.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
I changed the fuel pump and truck ran great for 3 days. Now after 3 days, the truck dies. It will start running for a few minutes, then dies like before.
ANSWER : Hi there, thanks for writing in. I’d be happy to help. It sounds like you should disconnect the connector to the fuel pump and inspect it for any signs of getting hot. The female connections may be too loose on the fuel pump and lose contact after running and getting hot. If there are indeed any signs of problems, then I’d suggest replacing connector and adding dielectric lube to pins before installation. This should solve the problem, but if you continue to experience issues, feel free to reach out to us for help again.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
ABS light comes on when I start driving – 1994 Acura Vigor
ANSWER : There is the possibility of a deeper electrical problem like a broken wire or corrosion inside a wire that may be very difficult to pick up on. Have an automotive technician experienced in diagnosing electical bugs dig out the problem.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
Car won’t start – 2004 Ford Focus
ANSWER : Hi and thanks for contacting YourMechanic. Check the battery cables for more corrosion and clean them up again. You may need to put backing soda and water mixture on the terminals to clean the corrosion completely off. Make sure that the cables are tight and also tight on the starter solenoid. By rocking the vehicle back and forth and using the clutch to start the vehicle, this is an indication that the cable on the starter is either corroded or loose. If you need further assistance troubleshooting your starting system, then seek out a technician, such as one from YourMechanic, to diagnose and resolve the issue.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
Why does my car struggle to start every 4th to 5th time?
ANSWER : It sounds like your starting issues may be linked to a problem with air metering or fuel delivery. A clogged or malfunctioning idle air control valve may show some of the same symptoms you are describing. The idle air control valve can be stuck in a cold start position which may work well if the car has been sitting a few hours, but as the engine warms up there must be a regulation in airflow. Consider hiring an experienced technician like one from YourMechanic who can come out for a closer look at your hard start situation and offer a more personal diagnosis.
Read Full Q/A … : ABS comes on under 3 mph and when starting out
