Trevorseaf Posted July 2 Share Posted July 2 Since purchasing the 2009 Mini Cooper non-turbo, I have been experiencing a misfire in cylinder 3. I have altered. Every every coil. Every every spark plug. Both variable valve timing (VVT) solenoids. Both cam sensors were affected. Two fuel injectors are needed for cylinders 2 and 3. Sealing gasket for a valve cover. Apologies, but I'm not sure what "Pcv." means. Could you please provide more context or clarify your message? Thermostat and housing. Comprehensive assistance Currently, there is no gasoline filter in place. Recently acquired AGM battery. The chain was replaced 30,000 miles ago. The compression test was conducted twice two weeks ago, and all results were within the acceptable ranges. I always have my Veepeak OBD2 device plugged in, and I just acquired a Creator C501. When I connect the c501, it fails to scan any codes, unlike the veepeak which is able to do so. Am I making an error in my procedure? Furthermore, it indicates the presence of a misfire in cylinder 3. Based on my observations, there are air flow problems specifically in cylinder 3/4. Quote Link to comment Share on other sites More sharing options...
SkippyTom Posted July 2 Share Posted July 2 Initial test to check the basic functionality of a system or software. The most probable cause of the issue is the leakage of valve seats, which is an often seen occurrence. Quote Link to comment Share on other sites More sharing options...
Trevorseaf Posted July 2 Author Share Posted July 2 Is the solution as simple as changing the valve seats, or are there more components such as valves that need to be replaced? Thank you. Quote Link to comment Share on other sites More sharing options...
DSM10000 Posted July 2 Share Posted July 2 Valve seats may get detached in naturally aspirated (NA) engines. This may be verified by doing a test, since it has a very distinctive attribute. Typically, the misfire becomes noticeable while the engine is running at its normal temperature and is not under load. When the camshaft sensor is removed, the ECU switches to safe mode, which disables the variable valve lift. This prevents the valves from making contact with the valve seats, ensuring a tight seal and preventing any leaks. However, if you continue to use it in that manner for an extended period of time, the seats will finally detach. Quote Link to comment Share on other sites More sharing options...
keithmerc220 Posted July 2 Share Posted July 2 Valve stem oil seals may experience leakage, leading to the accumulation of carbon deposits. The seats themselves should be satisfactory. However, it is necessary to remove the valves, clean them, and then reseat them. Quote Link to comment Share on other sites More sharing options...
Trevorseaf Posted July 2 Author Share Posted July 2 Greetings, keithmerc220 Quote Link to comment Share on other sites More sharing options...
SkippyTom Posted July 2 Share Posted July 2 Spared me the effort of typing it Quote Link to comment Share on other sites More sharing options...
SkippyTom Posted July 2 Share Posted July 2 I have primarily observed this phenomenon in engines that have been overheated or are running very lean. In most cases of overheated cars, the seats in the cylinder head have dropped out. At this point, the decision arises whether to take the risk of installing new seats only to discover that the head is cracked. I have encountered this situation a couple of times, and the second time I concluded that it is more prudent to replace the head when overheating causes the seats to drop out, as it eliminates the risk and provides a better way forward. Quote Link to comment Share on other sites More sharing options...
Auto Car Forum For Everybody
Auto Car Forum For Everybody
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.