In the winter I sometimes got an EGR code then it would go away. Replaced the EGR valve with cheap China one now getting Cylinder 4 misfire. I got a slightly used supposedly known good one from eBay (looks decent) same 304 code. If I block off the EGR tube 304 code goes away but get EGR code. I changed the ECT and IAT sensors thinking the ECM does not know the engine is warm and may be keeping the EGR open. What could be causing this? Head gasket? I know the EGR takes from cylinder 4 in this engine, should the EGR fully close when the engine is warm or does it stay slightly open all the time?
Hi there. The Exhaust Gas Recirculation (EGR) valve may be not designed for the emissions requirements for U.S. standards. If the EGR is pulling from cylinder number 4 and after replacing the EGR and the computer detects a misfire, then the EGR is malfunctioning and not responding. When you close off the tube to the EGR and the EGR light comes on and the misfire light goes out, then the EGR is not responding to your emissions system. I recommend replacing the EGR with the OEM specified part for the engine and all of the issues should go away. If you need further assistance with your misfire and EGR, then seek out a professional, such as one from Your Mechanic, to help you.
How to Identify and Fix Common car Problems ?
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While error code P0304 indicates a misfiring cylinder, the root cause can be many. Your car`s ECM may trigger this trouble code due to a faulty fuel injector, a leaking intake gasket, or low fuel pressure, among other things.
Chances are extremely high that the cylinder if misfiring due to a faulty spark system. This is, by far, the most common cause for this issue. You should start by checking the spark plugs and replacing any that need it. If you are overdue to replace your spark plugs, you may want to replace them just to be safe.
Diagnostic trouble code (DTC) P0304 stands for “Cylinder 4 Misfire Detected.” The code indicates that the powertrain control module (PCM) has counted enough misfire events on cylinder 4 to store the misfire code for that cylinder. Cylinder refers to the fourth cylinder as the cylinders are numbered.
You may report a P0304 code if your car indicates a misfire or an ignition or fuel system issue. As a result, it may result in an internal engine failure. This is a significant problem that requires immediate attention.
Do not keep driving with this error code. Repair Urgency: Fix this code immediately (same-day if possible) to avoid serious engine damage and dangerous driving conditions. Diagnosis: A multiple misfire can be caused by anything from faulty spark plugs to low engine compression.
An engine misfire can be caused by bad spark plugs or imbalanced air/fuel mixture. Driving with a misfire isn`t safe and can damage your engine.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
The most common causes of misfires are worn, improperly installed, and mishandled spark plugs, malfunctioning ignition coils, carbon tracking, faulty spark plug wires and vacuum leaks.
Engine misfires happen when one of the cylinders does not produce sufficient spark or compression and lack of fuel. It could involve more than one cylinder. It can be caused by a faulty spark plug, fuel injector, ignition coil and or worn cylinder.
An engine misfire results from incomplete combustion (or zero combustion) inside one or more cylinders. But to you, the problem will usually feel like hesitation or shaking when the car is running. In modern vehicles, the Check Engine Light will also pop on when there`s a misfire.
A P0300 code would indicate a random misfire (probably due to a vacuum leak, open EGR valve, etc.). If the last digit is a number other than zero, it corresponds to the cylinder number that is misfiring. A misfire code P0301, for example, would indicate a misfire problem in cylinder #1.
The code will not clear itself however after it is repaired the check engine or service engine soon light should go out.
Low engine oil can cause a misfire, and it is very likely that the cause of the misfire was indeed the low oil pressure in your vehicle. There are three common ways low oil can cause a misfire: Your oil filter is damaged, reducing oil flow, causing improper valve timing, and resulting in a misfire.
If left untreated, a cylinder misfire can lead to significant engine damage. Worse, if you experience a bad misfire while driving, it could result in an accident. This is why it`s important to treat engine misfires as soon as you detect them.
However, most misfires dissipate, and your engine regains its normal speed after a second or two. But even a single misfire is usually a sign that something else is wrong and that more misfires will likely occur in the future.
If your vehicle is in limp-in mode, you may have a top speed of 40 mph or less. Chances are that if you have a P0204 OBD-II trouble code, your vehicle will be running poorly enough that it won`t be very drivable. In any event, ignoring a P0204 code for long can lead to further engine damage.
Dead fuel injectors cannot be repaired and should be replaced with the exact same unit.
The most common fault codes associated with a clogged fuel injector are P0171 and P0174, which indicates the engine controller is seeing a lean condition. It is also possible to see fault codes for a rich condition if the injector is leaking or not atomizing correctly.
An engine misfire happens when the cylinders in the engine don`t burn right or the combustion within the chamber is incomplete (or nonexistent!). Typically, engine misfires can be caused by a variety of factors, including malfunctioning coils, worn or faulty spark plugs, a leak or a faulty ignition switch.
The code will not clear itself however after it is repaired the check engine or service engine soon light should go out.
An engine misfire can be caused by bad spark plugs or imbalanced air/fuel mixture. Driving with a misfire isn`t safe and can damage your engine.
The code will not clear itself however after it is repaired the check engine or service engine soon light should go out.