I have a Nissan Xterra that has been chugging for a few months now. The problem is intermittent and only happens about once or twice a week when driving, but when it starts to chug feels like it is running out of gas, jerky, will not accelerate it is unsafe to drive on the freeway.
I have taken it to several places and no one can figure out the problem. It was pulling two codes the speed sensor on the transmission PO - and the knock sensor code was coming up along with that. I had the speed sensor replaced twice and checked the wiring. We replaced the fuel filter, checked the fuel pump with a fuel gage and fuel lines, replaced the distributor cap and rotor, put in a new MAF sensor and still nothing is working to remedy the chugging.
Several other mechanics around town tell me that they are wrong and I do need to replace it. Does anyone have any input on this? Please help with any advice. Perhaps you could report the specific code. Its just a box of wires hooked by wires to other wires. I doubt your symptoms are from that though. You should troubleshoot the speed sensor code. Note that I said troubleshoot the code. The faulty knock sensor will not cause the Check Engine light to come on nor will it cause the driveability symptoms you describe.
The cost for knock sensor replacement is that high because it involves removing the upper and lower intake manifolds for access.
But replacing it will almost certainly not correct your problem. Your problem should be easily found if the mechanic is equipped with proper diagnostic equipment and the problem occurs when he is driving your truck with the test equipment hooked up. If the problem only rears its head once or twice a week you may need to leave your truck with the shop for a week or so.
But I can say that the scenario for a shorted knock sensor a common failure on Nissan V-6 engines to cause a fault code P for a Vehicle Speed Sensor would involve a rodent eating wire insulation off of your engine harness causing some crossed wires. Or some other strange thing. Not impossible, but certainly far from probable.
But once again, a faulty knock sensor will not, can not, on your car cause the symptom you are describing. Since this problem is intermittent, it may take some time for road testing to properly diagnose. This mechanic I just took it to drove my car around for over 20 miles and a full tank of gas after a week and all he came up with is the knock sensor. If it were you…what would your next step be. Please any suggestions would be greatly appreciated.
Sometimes they get balky and act up followed by straightening out for an undetermined amount of time and then going stupid again. Unless the pump acts up while the fuel pressure test gauge is in place and being monitored it can be pretty much a wild guess about this problem although replacing a pump on a wild guess is a bit distasteful. I would add that if the fuel filter has not been replaced regularly that is something that can contribute to pump failure because a partially clogged filter which may not have any noticeable symptoms can cause the pump to work harder than it normally would.
In the case of a Mitsubishi my daugher owned, I drove the car around for a week before it acted up and quit running on a deserted road with the ambient temperature about a At that point I determined the pump was the problem and lucky for me about half an hour later the engine started and got me home with nothing more than a few minor hiccups on the way. I replaced the pump the following day and the car was never a problem after that.
If I need to keep your car for a week, I will. Doing that, it should be possible to duplicate the concern. And an experienced tech can probably tell by feeling the concern if the problem is related to fuel supply, ignition, fuel delivery, engine sensor, or even electrical. As far as testing, a fuel pressure gauge is no longer the only way to test a fuel pump. This gives lots of information to someone who knows how to interpret it.As time passes a loud engine knocking sound eventually starts being heard driving it.
I was driving to school one day and I reach a stop light the car starting intensely shaking and the sound gotten louder and the oil light came full on, ive stopped the car on the side of the road and noticed little bits of oil on the engine cover, I turned it back on after 15 mins and managed to bring it to schoolI finished class and drove it normally but with caution.
Hi Dominic. Thanks for submitting your question today. When the oil pressure is low or oil level is low, internal engine components that depend on proper lubrication will start to wear metal-to-metal.
This can and often does cause the knocking or grinding sound.
Is your ‘check engine’ light on? Here are 10 possible reasons why
This is a situation that should be inspected and repaired by a professional mechanic as soon as possible. So, I would recommend having one of our mobile mechanics come to your location to complete an oil light inspection. This will allow them to inspect the vehicle at your home and determine the best course of action. Q: low oil pressure light is on and loud engine knocking asked by Dominic. My car has miles. My car has an automatic transmission. Tim Charlet Automotive Mechanic. Thank Tim. Was this answer helpful?
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Components like control arms can be lighter and thinner. Ball joints are riveted or pressed into control arms. Since replacing a ball joint will Read more. A coolant leak can come from a number of places under the hood. Typically, if it just started smoking all of a sudden, it is because a hose failed or the water pump is leaking. I typically get How do I use the sunvisor? The sun visor is a safety feature that can help keep sunlight and glare out of your eyes.The noise isn't like "wow, thats gonna wake up the neighbors" but, it's noticable.
I just bought a used car today from a friend of mine. I drove it to the next town over, no problems. Then, I was sitting at a light, and it just died. I retarded it, and it's been knocking ever since? If I had a serious problem, wouldn't the engine light come on?
When I came home, I checked the oil, and the dipstick was completely dry. But, I put more in it, and it quited the knock, but it's still there. So, if it were something serious, wouldn't my engine light come on? The oil light has been on for months. Auto Zone plugged a computer into it and said nothing was wrong.
A check engine light usually means one of two things - you have a problem with your emission system or there is a problem with the engine computer, sometimes major engine failures such as blown engine rods, overheating or running with no oil will not trigger the check engine light. Well if you ran it out of oil chances are you spun a bearingwhich means serious problems internally,and no the engine lite may not come on. So if you have a blown crank bearing the engine would have no way of knowing.
Doubt it's a rod though, that would cause a serious clatter. I suggest draining the engine oil then inspecting it for any pieces of metal. This will let you know if anything if broken or cracked in the housing. Update: I just bought a used car today from a friend of mine. Update 2: The oil light has been on for months. Answer Save. Not necessarily. The check engine light primarily monitors emission system functions.
Daniel C Lv 4. How do you think about the answers? You can sign in to vote the answer. Brandon Lv 5. Still have questions? Get your answers by asking now.So, Flashing or blinking warning lights or check engine light indicators; should be addressed as soon as possible.
Furthermore, Warning lights on the dashboard are simply that; warnings. Consequently, If one of the lights stays on after you start your car, you could potentially have a problem; and should have your vehicle inspected for needed repairs. Consequently, The code can be read with an electronic scan tool or a diagnostic computer. In addition, This is usually standard equipment in auto repair shops. There are also a number of relatively inexpensive code readers; that are designed for do it yourself.
Therefore, If one of the lights stays on after you start your car; you could potentially have a problem and should have your vehicle inspected for needed repairs. This has been known to happen before, so make sure that any problems with your vehicle are checked before embarking on any long drives.
This should help cover any damage or injury costs. However, to prevent the need for that, cars should be regularly maintained. So, Before replacing any of these sensors, you must first find the real problem that pushed you […]. Automotive emission control systems help control fuel fumes; while cleaning engine producing exhaust gases.
Consequently, these systems have been efficient in reducing air pollution caused by automotive engines. Also, increased engine efficiency and lighter vehicle […]. So, Diagnosing the cause of engine stalling issues can seem like a complicated job. Furthermore, The […]. Most of the images displayed are of unknown origin. We do not intend to infringe any legitimate intellectual right, artistic rights or copyright. Dash Warning Lights. Electrical System. April 19, Electrical SystemEmission Control.
Emission Control. December 12, Emission Control. Poor Performance. December 23, Poor Performance.The orange, engine-shaped icon that flashes in the instrument cluster is its way of letting you know it needs attention. Sometimes, the fix is cheap and simple. Here are the 10 most common problems that can trigger a check engine light. An engine will keep running even if an O2 sensor needs to be replaced, but it will burn more fuel than usual. In the long run, a bad O2 sensor can damage components like the spark plugs and the catalytic converter.
It may also cause a car to fail an emissions test. Finally, keep in mind that most late-model cars have more than one O2 sensor.
Why your car's engine might be knocking (Hint: it's not the oil)
A loose fuel cap is one of the most common reasons why the check engine light turns on. It notably prevents gasoline fumes from leaving the fuel tank, and it helps keep the whole system under the correct pressure. It turns the carbon monoxide generated during the combustion process into carbon dioxide.
Every late-model car that runs on gasoline has a catalytic converter. And as always, keep your eyes and ears open for unusual sounds or discolored smoke coming from the exhaust. Classic cars have a single coil, but many modern vehicles use one coil per cylinder. If your ride has a V8 under the hood, you could have eight separate coils. The monstrous Bugatti Chiron has Speaking of spark plugs, worn or fouled plugs can cause a variety of issues including an engine misfire and hesitation under heavy acceleration.
A worn coil can exhibit the same symptoms, and can cause the car to shut off unexpectedly. As its name implies, a spark plug wire transfers electricity from the coil to the spark plug. The vast majority of cars use a single wire per cylinder, but there are models — notably, some older Mercedes-Benzes — with two spark plugs per cylinder, and consequently two wires.
Symptoms of bad spark plug wires include a rough idle, a noticeable drop in engine performance, and lower gas mileage.Enter your zip code below to get your FREE estimate and see how much your car is worth.
Get paid the real cash value of your car in hours! In life, the two constants are death and taxes.
In car ownership, the two constants are maintenance and repairs. The two are inescapable if you plan on keeping your car for any length of time. And despite your best attempts at routine services and fluid changes, problems can still happen. When you car starts making noises that aren't normal, it's an indication that something is going wrong and it's time for maintenance or repair.
Noises like these are clues into problems, both large and small, that can happen to anybody, regardless if your car is new or old. Sometimes a car makes a loud noise on acceleration or you might find your car making squealing noises when you start it. Some of these noises are minor repairs while others have the potential to ruin your budgeting for the year.
Or in worst case scenarios, your car could degrade into a state where insurance declares your car a total loss. No one wants that, but if that happens selling your totaled car is probably your best bet.
Engine Rod Knocking - Everything You Need to Know
So here are the top potential issues a car can go through. Car knocking sounds may be the infamous spark plug knock, which could lead to serious engine damage and expensive repairs. When your engine knocks it's likely you will soon face high repair costs. In this case, selling your car is preferable to spending so much on parts and labor. CarBrain makes fair market offers on cars in any condition, running or non-running. See how much you can get for your damaged car now. It can be an issue as small as bad-quality fuel that causes an engine knocking sound.
Engine knocking noises can also be caused by:. A rod knock sound is one of the most serious problems. If left unattended you could seize your engine. An engine knock fix could be anything from a few hundred to several thousand dollars. For example, engine knock related to poor octane content in your fuel may only require refueling your tank.
Your vehicle may not be worth the cost of the repairs. The speed limit decreases, so you press your brakes. Clunking when you brake can be caused by one of several things like a seized brake caliper, an extremely loose wheel bearing, or even worn out ball joints or steering components. When you have a clunk, that means there is play where there should not be.
If you have a loose wheel bearing or hub, your wheel is flopping side to side instead of moving true in the direction you have steered your car. The same goes with worn ball joints and steering components. Clunking when you press your brakes is an indicator of a safety item. It might be a simple brake pad replacement or a complete suspension and steering system overhaul.
If you hear grinding brake noise, scraping brake noise, or clunking you should get your brakes inspected right away. Or, it could be more serious like your bumper cover flapping in the wind. A flapping sound from under the hood is commonly the fan belt starting to fray. It could also be something interfering with the fan blades - something like a block heater cord.
It only takes a minute to sign up. What is a rod knock? What causes a rod knock, how bad is a knocking rod, and how can I tell if a rod is knocking? To get to basics, the rod or connecting rod is the portion of the engine which connects the piston to the crankshaft. Where the rod connects to the crankshaft there is a bearing which separates the rod itself from the crank journal. The bearing is made from a softer material than the rod or the crankshaft.
The connecting rod is 7, the crank shaft is 16, piston 4, and bearing can be found marked as 8. When an engine is built, there are certain gap tolerances specific distance measured in. In this case, the tolerance is there to allow a specific amount of oil through from a hole in the crankshaft journal and remain on the bearing surface.
Oil films on the bearing and keeps the two parts from touching during normal engine operation. If the clearance gets too big from either wear or deformation, the oil will no longer film correctly and you will get the rod knock.Fixing a Rod Knock - Engine Disassembly and Tear Down
The noise itself occurs due to metal on metal contact between the bearing and the crankshaft journal during the power stroke of the engine cycle. If the situation is really bad it can even be caused by the rod itself contacting the crankshaft journal where the bearing has become out of place.
The most common cause of rod knock is due to a spun bearing bearing itself actually spins in the end of the rod so it becomes out of position. This usually happens due to rod cap stretch during abusive driving situations.
It can also happen due to a lack of lubrication, either because of a lack of oil or because oil is flowing incorrectly. It can also be caused by a combination of any or all of the three. A rod knock is a very serious issue with the engine. As you can probably tell from my write-up, it means the engine is no longer functioning correctly. It is the death knell of the engine. Once the rod knock occurs, it will not cure itself.
The rod bearing must either be replaced along with fixing associated parts you don't usually replace just one rod bearing as the entire engine would need rebuilt at that pointor the engine will need to be replaced.
A rod knock is as described A low pitched knocking sound which can be heard low in the engine.