Car still runs bad. Replaced fuel and oil filter. Also replaced knock sensor and got an oil change. Car stalls and has slow speed.
I was getting the P0172 and P0171 codes when I got a diagnostic. I got the sparkplugs changed and it ran a little better. I got the fuel filter changed and the oil filter changed and it ran a little better. Then I got the knock sensor changed and it ran a little better. It still stalls and runs slow. It is also slow to accelerate. What else can be the problem? Could you provide a list of possible fixes to this problem?
My car has 204000 miles.
My car has an automatic transmission.
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If you have replaced the knock sensor, then defenitly reset your ECU. Once that is complete, you should have full power almost immediately. no nothing bad will happen from resetting your ecu. but it will take your engine about 50 miles (from my experience) to relearn everything.
The knock sensor could be missing entirely and it would not prevent your car from starting. You can drive with a bad knock sensor, but it could have adverse long term effects on your engine if there is a lot of pre-ignition, and the car will not pass most state inspections until it is fixed.
CAUSES FOR FAULTY KNOCK SENSORS: CAUSE OF FAILURE
Wiring short circuit. Mechanical damage. Incorrect mounting. Corrosion.
Either there is still another issue causing the engine light to come on or you need to reset the ecu or possibly the the Knock sensor you put in is defective. I`d go with reseting the ecu first and to do that depends on the make of vehical .
Bad Engine Performance
A malfunctioning engine knock sensor can cause the PCM to wrongly adjust the ignition timing, resulting in inadequate engine performance. The engine may not feel right while driving at high speed or when the vehicle is carrying a weighted load.
Yes, you can drive with a bad oxygen sensor if you can still start your engine and feel little difficulty driving. But don`t leave it alone for over a couple of days, as it might cause safety problems and lead to the malfunction of other parts of your vehicle.
The knock sensor detects vibrations that come from a knock or an irregularity in combustion and send a signal to the engine control computer, which then adjusts timing to correct the knock.
How Do You Know If Your NOx Sensors Are Faulty? The NOx sensors tells the ECU how much DEF should be injected into the exhaust before it enters the SCR. If the sensors are faulty, you`ll likely see increased DEF consumption and fuel spending, alongside erratic or unstable idling.
If a knock sensor-related code is set, the ECM may use a more conservative fuel map or even limit engine loads and RPM. This is to protect the engine and safeguard against possible damage to the combustion chamber.
Disconnecting it will not give you any direct data. If there is a real knock problem, you could end up damaging the engine. Second, if there is an issue with the knock sensor itself, you`d most likely get a trouble code of P0325, which is about a circuit malfunction.
In most cases, there is little to clean and reuse as when a sensor goes out of calibration from wear or mechanical damage, or fails due to heat damage, the only repair is to replace them.
The easiest way to perform an ECU reset is by removing the fuse from the fuse box. It is a very simple process, and all you have to do is pull out the car key, remove the fuse from the fuse box, and then put it back after about 15 to 20 seconds. Doing this clears any long-term memory stored in the car`s ECU.
If the lambda sensor is defective, no data will be sent to the ECU, which will then use faulty information. This will most likely increase the fuel consumption, and subsequently, the polluting emissions. Eventually, this may lead to the clogging of the catalytic converter, which you will then have to replace.
The oxygen or lambda sensor is one of the most important and one of the most misunderstood components of a modern fuel injection system.
Knocking occurs when fuel burns unevenly in your engine`s cylinders. When cylinders have the correct balance of air and fuel, fuel will burn in small, regulated pockets instead of all at once. (Think sparklers, not fireworks.)
Piezoelectric ceramic sensor for the detection of vibration caused by engine knocking. Knock sensors are used for ignition timing control that contributes to improved engine performance and fuel economy.
Typical 2 wire knock sensor circuit with Bias Voltage – 2.5V with sensor connected. (other wire ground). This sensor has a flat frequency response over the 5 to 18 kHz range.
To test a knock sensor, tap a wrench on the manifold or cylinder head close to the sensor (be careful not to hit the sensor). The timing should change a few degrees when the engine is idling. If the timing doesn`t change, the sensor may have failed.
Most knock sensors operate based on the first method. Vibration detection sensors can be divided into three types according to their sensing mechanisms: inductive resonant sensors, piezoelectric resonant sensors, and piezoelectric non-resonant sensors.
This is particularly important if the NOx catalytic converter has been replaced. Of course, you can reset the NOx sensor by yourself. Use a special obd2 scanner, follow the steps according to the prompts, and you can realize NOx sensor reset.
The NOx sensors warn the driver if the emission is as it should be. If the NOx sensor is defective, the system switches to an emergency operation. This also results in increased fuel consumption, engine misfire and uneven acceleration.
The P0325 code is a generic diagnostic trouble code (DTC) defined as “Knock Sensor Circuit Malfunction (Sensor 1, Bank 1).” DTC P0325 occurs when your engine control module (ECM) or powertrain control module (PCM) receives improper readings from the knock sensor circuit.
A knock sensor can last for 150,000 miles or more, but it could fail sooner for any number of reasons. If you notice any symptoms that you need knock sensor replacement, you should get it fixed as soon as possible, whether you have a shop fix it or do it yourself.
The oxygen sensor problem is the number one reason cars are slow to accelerate. The oxygen sensor is responsible for monitoring the air-to-fuel ratio in the engine, and over time it can become dirty or damaged, which will decrease power. Oxygen sensor malfunction will result in a mixture being too lean.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
I have a p0171 code on my ford ranger 2.5 and have replaced fuel filter maf sensor, iac sensor, fixed vacuum leaks, replaced fuel
ANSWER : Hello there. You might to read this article about the P0171 OBD-II trouble code; as it will give you ideas on causes and possible solutions.
lost all oil pressure, replaced the oil pump, low oil sensor, oil pressure sensor, oil pan gasket,
ANSWER : The fuel pump will not stay on if you loose oil pressure. This is why it is shutting off. The loss of oil pressure may be from bad crankshaft bearings or camshaft bearings. The engine oil pan should be removed and the oil pump needs to be checked to ensure that you put in the pick up tube seal to the pump and connected the pump to the block. Then remove at least one main bearing cap and inspect the bearings for excessive wear and crankshaft damage. If you need some help with this, consider YourMechanic, as a certified technician can help diagnose the issue with your oil pressure firsthand and help you fix it accordingly.
My car is leaking oil i got an oil change for it last month but it is still leaking oil what will cause my car to leak oil ?
ANSWER : Most older cars have oil leaks. Sealing technology has just not kept up with mechanical improvements to engines so much so that leaks often kill engines rather than mechanical problems. So, it is not unexpected at all to have an, indeed many, oil leaks on a 23 year old car. Oil leaks vary hugely in terms of severity and priority of repair. Oil leaking onto a hot engine manifold is the worst case (the oil can start a fire; at best, you are left breathing oil fumes in the cabin, as the oil burns off of the manifold) while de minimus seepage of oil at the oil drain plug or oil pan gasket, while annoying and messy, if limited enough is not an emergency. Some leaks are easy to repair, while others literally require the engine to be removed just to get physical access to all the leak points. In your circumstance, if you smell burning oil, oil is probably leaking onto a hot engine part such as the exhaust manifold. A certified Mechanic, dispatched by YourMechanic right to your location, can perform an oil leak diagnostic and then let you know of your repair options and costs.
As far as the check engine light, that is not related to the oil leak(s). If you request a check engine light diagnostic, a certified mechanic from YourMechanic would use a code scanner to retrieve the specific diagnostic trouble code(s) from your car’s PCM that have caused the check engine light to illuminate. Using those codes, the appropriate individual vehicle components or sub-systems (often a sensor, circuit, and the like) are then carefully tested, based on specifications set forth in your car’s Factory Service Manual, to pinpoint the cause of the fault or the reason why the check engine light has illuminated. Once the faulty part or component is identified, it is explained to your satisfaction and the mechanic will let you know of the cost to repair. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
2006 BMW oil filter gasket keeps breaking and oil leaks from oil filter. Oil leaks only after starting car in morning. PCV valve?
ANSWER : Hi There,
It sounds like you may need to replace the oil cap o-ring. If you haven’t done this before there are two O-rings to replace; a small green one on the base of the filter cap stem and the large black one that seals the filter cap (which seems to be the one you are having issues with). The large O-ring sits in a small square-shaped groove that is at the base of the oil filter cap. It is very easy to not properly seat the large O-ring because the threads for the oil cap are quite large and will accept the O-ring if you are not careful. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.
It sounds like you may need to replace the oil cap o-ring. If you haven’t done this before there are two O-rings to replace; a small green one on the base of the filter cap stem and the large black one that seals the filter cap (which seems to be the one you are having issues with). The large O-ring sits in a small square-shaped groove that is at the base of the oil filter cap. It is very easy to not properly seat the large O-ring because the threads for the oil cap are quite large and will accept the O-ring if you are not careful. I would suggest having a professional from YourMechanic come to your location to take a look at your vehicle.
Oil still leaking after I changed oil filter
ANSWER : Unless there is an imperfection (e.g., serious pitting or irregularities) on the engine mounting base for the filter gasket, the leak is probably not at the filter. There are other adjacent potential leak spots such as the oil pan gasket, oil pressure sending unit and so forth. If the leak is significant at all, merely thoroughly cleaning the suspect area and running the engine while looking for the leak should be sufficient. If you still can’t find the leak origin, a UV visible dye can be added to the engine oil which will then make the leak point visible using a detection light. If you want these steps performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an oil leak diagnostic and the responding certified mechanic will get this taken care of for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
just got a oil change Car engine temp got really hot, oil spilled under the hood, loud screeching and smoke when the car is on
ANSWER : Hi there. I honestly hate hearing horror stories like this and am very sorry this has happened to you. There are several things that could have caused this issue, ranging from the oil service place forgetting to put the oil cap back on, tighten the oil pan bolt or the oil filter was improperly installed; causing the oil to spray, increase engine temperature and many other possible damage to internal engine components. The first thing I would do is contact the oil service location and inform them of the problems you have experienced. They should be given every opportunity to resolve and repair this issue; or at least, have an "accident claim" filled out by you; as it’s possible that major damage may have occurred. If they are unwilling to help, I would set up an oil leak inspection from one of our professional mechanics so they can determine where the oil is leaking from and any other damage that has occurred. In the best case scenario, the issue can be resolved easily.
the car is acting like its getting to much fuel. changed the fuel pump, fuel filter, and the fuel pump relay.
ANSWER : There could be a few things contributing to your problem. You are correct that clogged or sticking fuel injectors and possibly the fuel pressure regulator could be faulty. A plugged catalytic converter can also cause the vehicle to bog down. A failing throttle position sensor can cause the symptoms you describe as well. I suggest having a certified technician, like one from YourMechanic.com, do a few tests to determine the exact cause of your starting concern.
Not getting enough fuel car will not run right. It stalls when you give it gas and stalls when it’s running. It’s a 1984 Ford Escort.
ANSWER : Hi there, thanks for writing in. Several early 80’s Ford’s swapped from carburetor to fuel injected engines; including your ’84 Ford Escort. However, there were two different fuel systems available that year. If your Escort has the fuel injected engine, one item I’d check is the EGR valve or clean the throttle body.
Both systems impact fuel delivery into the engine and if they are dirty or clogged with excessive carbon build up, can starve the engine to create this type of issue. If it’s the carburetor version, the carburetor might need to be rebuilt, or may be an issue with float bowls inside the carb.
If you need assistance diagnosing the exact issue, feel free to contact one of our professional mechanics to complete an engine is stalling inspection firsthand at your own location.
