nwoods
Expedition Leader
My son's 2002 WJ has 200,000 miles on, with a freshly rebuilt motor. We bought it a few months ago, and didn't rebuild the motor ourselves, so we aren't sure how complete a rebuild it was, I suspect not very, because in the past few months we've had to replace all the major sensors, including crank sensor, TPS, etc....
Currently, it's not running, or barley running. It has a significant misfire on Cylinder #7, indicating P0307. It sounds terrible at the tailpipe, though it idles okay, with only a minor hickup audible from the engine bay. However, there is a lot of white smoke coming out the tailpipe once it warms up, and its got no power at all. It is loosing coolant, but not huge amounts, there is a small coolant leak between the hose and the radiator that could be the source of lost fluid.
We pulled the spark plugs for #5 and #7, and #7 (the misfire cylinder) has a lot of oil on the spark plug head, and is fouled and gunky.
There aren't any bubbles or gasses coming up through the radiator, but there is a smell of oil near the rear of the engine (near Cylinder #7), and some white smoke drifts up from near the exhaust manifold in the same general area
So I'm confused, it doesn't seem like a blown head gasket (no bubbles, not enough coolant loss to cause a misfire), and it doesn't quite seem like a fallen rocker arm (no tapping noises), and it doesn't seem like cracked manifold (no exhaust noise near the engine).
Any thoughts? I am really not sure what do next? I'm going to remove the valve covers and see if there is any visible issue with the rocker arms, but I suspect they are okay (recently rebuilt motor...). I'm wide open to ideas or suggestions. I am not a mechanic, and have no experience to draw on other than a Montero with a bad cylinder that I was unable to fix and eventually sent to the crusher.
Currently, it's not running, or barley running. It has a significant misfire on Cylinder #7, indicating P0307. It sounds terrible at the tailpipe, though it idles okay, with only a minor hickup audible from the engine bay. However, there is a lot of white smoke coming out the tailpipe once it warms up, and its got no power at all. It is loosing coolant, but not huge amounts, there is a small coolant leak between the hose and the radiator that could be the source of lost fluid.
We pulled the spark plugs for #5 and #7, and #7 (the misfire cylinder) has a lot of oil on the spark plug head, and is fouled and gunky.
There aren't any bubbles or gasses coming up through the radiator, but there is a smell of oil near the rear of the engine (near Cylinder #7), and some white smoke drifts up from near the exhaust manifold in the same general area
So I'm confused, it doesn't seem like a blown head gasket (no bubbles, not enough coolant loss to cause a misfire), and it doesn't quite seem like a fallen rocker arm (no tapping noises), and it doesn't seem like cracked manifold (no exhaust noise near the engine).
Any thoughts? I am really not sure what do next? I'm going to remove the valve covers and see if there is any visible issue with the rocker arms, but I suspect they are okay (recently rebuilt motor...). I'm wide open to ideas or suggestions. I am not a mechanic, and have no experience to draw on other than a Montero with a bad cylinder that I was unable to fix and eventually sent to the crusher.
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