check engine codes P0303/P0306 cylinder 3/6 misfire
How do I repair this?
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drove about 60 miles and then started to get a miss and loss of power (particularly up hill) and the check engine light was either flashing or steady.
borrowed a OBD tester and got codes P0303/0306 cylinder 3/6 misfire. I see a "square" module on the front of the engine near the oil cap with an ignition wire labeled "3" and a second connector that looks like it leads to a fuel injector. The connectors are a mystery as I cannot figure out how to open them.
Because of the engine "V" shape, I cannot see if there is a reciprical "square" module and is the problem in one, both or not these modules?
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Hello marcjames,
First, I would like to thank you for reaching out to us! Diagnosing misfires can be very tricky, because the ignition system is made up of several different components that all must work together perfectly, every time. Best case scenario you just need new plugs and coils, worst case scenario the engine has lost compression to the point that the air/fuel mixture in the cylinder is not firing properly. The best way to handle this is to have the issue looked at by a certified technician, who will then be able to tell you exactly what is going on and avoid your money being wasted on ineffectual repairs. Measure twice, cut once! We would be more than happy to take a look at it for you and figure it out. The Siennas are great vehicles and I am confident we can get you fixed up in no time!
Did some additional checking on line and learned that the 3 coils fire 2 cylinders per coil and what the numbering sequence is for the cylinders. Swapped the 3/6 coil with the next one over. Engine still ran rough but the code followed the misfire to the same coil. Ordered a new coil on line and installed it. Engine running smooth now, just need to test drive it. Thanks for the reply.
Did some additional checking on line and learned that the 3 coils fire 2 cylinders per coil and what the numbering sequence is for the cylinders. Swapped the 3/6 coil with the next one over. Engine still ran rough but the code followed the misfire to the same coil. Ordered a new coil on line and installed it. Engine running smooth now, just need to test drive it. Thanks for the reply.