The truck intermittently, has a very rough idle, and runs rough,usually after warming up.
The truck was running fine until a fill up a few weeks ago. Shortly after I filled the tank, it started running rough and idling rough. I ran some sea foam, and then fuel injector cleaner through it. Then changed the fuel filter, and now have changed the spark plugs. I had changed the plugs previously and wires at 100k. The truck seems to run fine when cold, but once at operating temperature, the idle becomes very rough, and sluggish on acceleration. I have also cleaned the M.A.F., the EGR valve, and checked the pcv valve. Motor appears to change and run better if I disconnect the MAP, but not
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Hello. This can be caused by a number of different things. If this occurred right after you had gotten fuel then I would start by testing the fuel pressure. I would do this when the vehicle starts running poorly. It is possible that the bad fuel contaminated the fuel pump and it is not putting out the right pressure. If the fuel pressure is fine then I would check the other sensors readings with a scan tool. One other common thing that I have seen on this engine is a leaking intake manifold gasket. It starts leaking on the bottom side and that leak causes the MAF and MAP to not read correctly which causes it to run like this. If you would like to have this rough running condition looked at, consider having a YourMechanic certified techniciancan come to your home or office to diagnose why it is running rough.
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A rough idling engine can be caused by spark plugs or spark plug wires. Spark plugs use the electrical current received from ignition coils to ignite the air/fuel mixture within the combustion chamber. A plug that is damaged or installed incorrectly can result in fuel being burned at an inconsistent rate.
Dirty/Faulty Fuel Injectors – Fuel injection systems play an essential role in starting your vehicle. The system injects fuel and air into the cylinders. If clogged or gummed up, the injectors don`t provide the right mix of fuel and air, resulting in a rough idle or slow acceleration.
How To Fix Rough Idle When Warm? Most likely, the causes of rough engine idle crops from the basic functional components like direct fuel injectors, PCV valve, EGR valve, Oxygen sensors, vacuum leaks, air filter, and spark plugs or wire.
A car that idles rough but drives smooth may be due to broken motor mounts. The purpose of motor mounts is in the name! These cylindrical components are what keep your engine in place. Broken or weak mounts are unable to support the engine properly, creating a vibration at idle.
A PCV valve that`s stuck open will allow too much air to enter the intake manifold, leading to a leaner idling fuel-air mixture. Stuck closed leads to a build up of pressure in the crank case which creates a variety of oil leaks! And this in turn can lead to a range of issues, including a rough idle.
Engine hunting and surging at idle is usually caused by a fuel delivery, air leak, or governor system problem. Cleaning/overhauling the carburettor, adjustment of the governor, and/or changing the air filer may be required.
A rough idle without any codes could be caused by various factors, such as vacuum leaks, a dirty throttle body, a malfunctioning idle air control valve, clogged fuel injectors, clogged air filters, poor quality fuel, or even a blown a fuse.
Erratic engine idle can be caused by various factors, but the most common and likely cause is a dirty or malfunctioning Mass Air Flow (MAF) sensor. This is a device found in fuel-injected cars and measures air flow so that the appropriate amount of fuel can be injected.
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The truck intermittently, has a very rough idle, and runs rough,usually after warming up.
ANSWER : Hello. This can be caused by a number of different things. If this occurred right after you had gotten fuel then I would start by testing the fuel pressure. I would do this when the vehicle starts running poorly. It is possible that the bad fuel contaminated the fuel pump and it is not putting out the right pressure. If the fuel pressure is fine then I would check the other sensors readings with a scan tool. One other common thing that I have seen on this engine is a leaking intake manifold gasket. It starts leaking on the bottom side and that leak causes the MAF and MAP to not read correctly which causes it to run like this. If you would like to have this rough running condition looked at, consider having a YourMechanic certified techniciancan come to your home or office to diagnose why it is running rough.
01 mustang v6 running rough at idle and drive. Please help. Replaced a bunch, still can’t figure out issue.
ANSWER : This may be a sign of a faulty MAP sensor as the vehicle responds adversely to a load put on the motor (i.e. putting it in gear, turning on AC or engaging the brakes). The Manifold Absolute Pressure (MAP) sensor senses engine load and generates a signal that is proportional to the amount of vacuum in the intake manifold. The engine computer then uses this information to adjust ignition timing and fuel enrichment. When the engine is working hard, intake vacuum drops as the throttle opens wide. The engine takes in more air, which requires more fuel to keep the air/fuel ratio in balance. When the computer reads a heavy load signal from the MAP sensor, it adjusts the fuel mixture to slightly more rich than normal so the engine can produce more power. The computer will then retard (back off) ignition timing slightly to prevent detonation that can damage the engine and decrease performance. This may also be caused by other closely related components such as a dirty or failing mass air-flow sensor, a faulty throttle position sensor or potentially a vacuum leak. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.
When the truck is rolling with clutch in the truck will idle rough and sometimes dies.
ANSWER : This is a common symptom of the idle air control valve failing. This unit monitors the air intake as it is mixed with fuel prior to entering the motor. When this fails, this will cause a rough idle at low RPM’s. I would recommend having an expert from YourMechanic come to your home to diagnose the rough idle firsthand for an accurate repair.
Vehicle started running rough while driving. Now running/idling rough running rich.
ANSWER : Hello. From the symptoms you describe, it would appear that your vehicle is having issues with the oxygen sensors. P0172 is the code for bank 1 being too rich. This can be caused by a wide variety of issues. The other two codes are for the sensors on bank 2, having excessively high voltage.
This may be due to the rich condition, faulty oxygen sensors, or faulty wiring. The black smoke and soot is a result of excessive fuel that is not being properly burned, and exiting the tailpipe as smoke. A few common causes for these symptoms are a bad fuel pump, fuel pressure regulator, or engine management sensor. As engine management systems can sometimes be difficult to diagnose, I would recommend having the rough idling issue inspected by a professional technician.
Rough idling when cold, would not idle when it warms up
ANSWER : Hello. It sounds like you have already changed a lot of parts on this. Most of the time, the issue is actually caused by a leaking intake manifold gasket. This is the most common issue on this vehicle. It leaks and causes a serious vacuum leak which affects the engine as you mentioned, but allows it to run fine at higher speeds or better once it is warm. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your car’s rough idling issue.
Engine won’t fire without ether and runs bad until it warms up.
ANSWER : Hi there. There could be a lot of carbon build up inside the combustion chamber making the fuel not burn properly due to the valves and rings not sealing. First check the spark plugs and see if there is excessive build up on the terminal. If there is, clean off the plugs with a wire brush and put them back in. Start up the vehicle and put in sea foam into the intake through a vacuum hose. You will need to keep the engine running at about 2,500 rpm’s to allow the sea foam to work. The more black smoke that comes from the exhaust pipe will let you know of how much carbon is built up in the engine. Then, install new spark plugs and put a can of sea foam in the fuel tank and top off the fuel tank. This will stabilize the fuel and clean the fuel injectors. If you need further assistance with your engine running rough and having to start the engine with ether, then seek out a professional, such as one from Your Mechanic, to help you.
The car idles rough and is shooting out codes p0017, p0016.
ANSWER : Hello. This is a common problem with the variable valve timing solenoid on this engine. I have changed quite a few of these due to failure. I always start by checking the codes and testing the solenoids and the connectors as some of the time the connectors fail and have poor connections. There have been a few times that I have seen these codes due to low oil or the wrong oil and from the camshaft actuators failing, but most of the time it is due to the solenoids. If you are planning on having this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose and repair the rough idling issue for you.
Just rebuilt the motor and had an issue with a misfiring, rough running engine when warmed up. It idles great at start up.
ANSWER : My best guess would be that this involves a crankshaft position sensor. They can do strange things when they are cracked or broken. Temperature has been known to affect the signal strength and clarity to the PCM. It is mounted on the top of the transmission bell housing on the passenger side. It is retained by two bolts and can be a little challenging to get to. If you did not remove it before you pulled the engine, there’s a good chance you bumped it with the engine’s flex plate. Finally, check for codes. If there are not any, I would still replace the sensor. They are known to fail around 150K. If you would like help having this done, a certified technician from YourMechanic can come to your home or office to diagnose your vehicle’s loss of power and assist you with any repairs.
