Car is idling at high rpm’s and when the days are hot the car cranks but doesn’t turn on and also exhaust is smoking when i rev it
So my car idles high in park & in hot days the car won't wanna turn on it cranks and it might turn on after trying to turn it on but then dies unless i give it gas, only in hot days also my car has been burning oil but no smoke has came from the exhaust till i added some oil and all of the sudden the car start smoking up from the exhaust when i drive or rev it. what could be the issue? it drives fine oil is a bit dark when i checked it tho and the car seems to drive normal.
My car has 126864 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
Hello – your symptoms suggest worn piston rings or valve stem seals (smoking), and a possible air leak in the intake, or idle air control valve sticking open (high idle). Both are signs of a higher-mileage engine with significant wear. I recommend an engine inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.
How to Identify and Fix Common car Problems ?
Our sources include academic articles, blog posts, and personal essays from experienced mechanics :
The most common problem is a faulty fuse. In modern vehicles, engine idle speed is most often controlled by the idle air control (IAC) motor. This can be impacted by bad fuses in many different electronic systems in your car. Next, your high idling could be caused by a computer malfunction.
This may be a sign of a failing idle air control valve. The idle air control valve is located on or near your intake manifold that monitors the air intake as it is mixed with fuel prior to being injected into the engine.
The engine`s oxygen sensor will detect the extra oxygen entering the engine via the vacuum leak which will alert the engine`s computer that the exhaust is running lean, which will prompt the computer to pump in additional fuel, resulting in an abnormally high idle.
A Broken Radiator Fan
If your car begins to overheat when idling, but the temperature gauge moves back down once you get going, it`s most likely due to a broken radiator fan. When the coolant goes to the radiator, it`s spread over a large surface area to cool it down.
Pull over and shut off the car. Allow the engine to cool for at least 15 minutes. Keep an eye on the temperature gauge, as it should move back to a normal range as the engine cools. While you`re waiting (and watching the gauge), put together a plan to get your overheated engine checked out.
An idle air control valve, also called an idle air sensor control motor, is an electrically operated valve that controls the amount of air that bypasses the throttle plate in cars with a fuel injection system [source: Autozone]. This causes the idling speed of the engine to change as needed.
If everything is working as it`s supposed to, the engine idle speed should always remain the primary constant. However, over a period of time some mechanical components that monitor or control the flow of fuel into the fuel injector will become damaged and may contribute to increasing or decreasing engine idle speed.
To check whether the idle air control valve is functioning properly, start the engine and let it run for about 10 to 15 minutes. If the valve is functioning correctly, the engine will sound good and the idle will be steady versus too high, too low, or inconsistent.
The idle speed should feel consistent without skipping or slipping. In most of today`s cars, an idle speed of 600 to 1000 RPMs is average. If your car is idling rough, though, it won`t feel smooth. The RPMs will jump up and down, for example, or they`ll fall below 600 RPM (or whatever is typical for your vehicle).
Idle speed is controlled by using an electronically controlled throttle bypass valve, as seen in Fig. 6.6, which allows air to flow around the throttle plate and produces the same effect as if the throttle had been slightly opened such that sufficient M . a flows to maintain engine operation.
The most common causes of this on your vehicle are either a bad idle control valve, a dirty or failing throttle body, or a vacuum leak. It is very common for the engine to have a vacuum leak at the intake manifold gasket.
Improperly functioning spark plugs cause an uneven burn of fuel in the engine, resulting in fluctuating RPMs and a louder noise. You might also experience increased vibrations of your vehicle while sitting idle or while traveling at low speeds.
Rough engine idle and misfires
Since the oxygen sensor output helps control engine timing, combustion intervals, and the air to fuel ratio, a bad sensor can disrupt these engine functions, causing a rough or irregular engine idle and other engine-related issues.
If your engine revs up as you press down on the gas but your vehicle doesn`t accelerate as much as you`d expect, you may be dealing with transmission slipping. If you`ve ever tried to accelerate on ice, where your engine revs but your vehicle goes nowhere, you know the feeling.
If your engine revs up as you press down on the gas but your vehicle doesn`t accelerate as much as you`d expect, you may be dealing with transmission slipping. If you`ve ever tried to accelerate on ice, where your engine revs but your vehicle goes nowhere, you know the feeling.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Car is idling at high rpm’s and when the days are hot the car cranks but doesn’t turn on and also exhaust is smoking when i rev it
ANSWER : Hello – your symptoms suggest worn piston rings or valve stem seals (smoking), and a possible air leak in the intake, or idle air control valve sticking open (high idle). Both are signs of a higher-mileage engine with significant wear. I recommend an engine inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.
Hey when the car idles it revs up and down by like 300 revs or so and also when the car is off it doesn’t recognize its in park.
ANSWER : The issue is the transmission position sensor is not working properly and registering that the transmission is in drive, neutral, or reverse. Check to see if the transmission is going into park when the shifter is in park. If the transmission is going into park, then the sensor is not working and needs replaced. If the transmission is not going into park, then the shifter cable may be broken or out of adjustment. If you need further assistance with transmission not going into park issue, then seek out a professional, such as one from Your Mechanic, to help you.
Cruise control turns on at idle, but when the car reaches 10 mph the cruise turns off and won’t turn back until idle again.
ANSWER : Hi there. Check all of the grounds to the vehicle and see if there is any wires that are damaged from the taillight short. A loose ground will cause multiple problems with the electrical system and some or multiple components will not work. If you need further assistance with your electrical issues, then seek out a professional, such as one from Your Mechanic, to help you.
Why does my car start one day and the next day it wont start? The car will crank but wont turn over
ANSWER : Hello, thank you for writing in. With intermittent symptoms, diagnosis can take longer but is typically the same as diagnosing any other starting problem. The main issue is that you can only perform the testing needed when the issue is occurring. If the vehicle starts and works normally, all of the components are likely going to pass their tests. There are several components that will work intermittently. They include the fuel pump, charging system, a number of sensors, and any electrical connection that is loose. When the vehicle is not starting, test for fuel pressure, spark, and the electrical connection on any of the sensors that effects starting (air intake, camshaft/crankshaft position sensors). For more diagnostic help, contact our service department to schedule an appointment.
My car wouldn’t revv above 3 rpm and when in motion, it doesn’t exceed 2 rpm, as such, it doesn’t select gear properly. The car
ANSWER : Hi there. To be honest, this problem could be caused by multiple fuel system or ignition system components. Some common reasons that an engine won’t accelerate properly include dirty EGR valve, mass air flow sensors, or clogged fuel injectors / throttle body issues as well. Some ignition components such as damaged or worn out spark plugs or distributor cap can also cause this problem. In order to correctly diagnose this problem, it would be best to have a professional mobile mechanic come to your location and complete a engine idle is rough inspection.
High Idle, stalls when a/c or defrost is turned on and dies completely after some rough idling. If turned back off car is fine.
ANSWER : Hi there. The fact you able to get the idle speed to drop by tapping the gas pedal, lead me to believe the high idle is due to a sticking accelerator cable. Another possibility could be, a faulty throttle body not allowing the throttle to return to the closed position. Proper diagnoses should be performed to avoid unnecessary repairs. I recommend having your vehicles high idle be diagnosed and repaired by a certified technician, such as one from YourMechanic.
As I’m driving, all my lights inside/out of the car turn off and the car still stays on. But when I turn the car off it won’t turn over
ANSWER : Hello there. The charging system on the car may not be charging the battery as you drive and the systems that keep the engine running are priority so the engine will stay running until the voltage drops below about 9 volts but the lighting and some other accessories may cut off above this voltage first. You should have the charging system tested to see if the alternator needs to be replaced.
Car won’t start after seeing engine hot turn a/c off warning light.
ANSWER : Hi there. Check the battery cables and make sure that they are tight and clean. Then check the battery voltage and see if it has a voltage of 12.6 or 12.4. If the battery is less than that, then the battery needs charged. If the battery has 12.4 volts or higher, then place a load tester on the battery and see if the battery can hold a charge when a load is applied. If the battery drops under 9.6 volts, then the battery is no good and needs replaced. If the battery drops to 11.5 volts, then there is a dry cell and possible a burned cell and the battery needs replaced. If you need further assistance with testing your car battery, then seek out a professional, such as one from Your Mechanic, to help you.
