97 Mark VIII, last weekend I swapped out the oil filter gasket, and pressure washed the BOTTOM of the engine, k member, transmission, etc as it was very oily and had coolant also. No problems after doing that, or for 300 miles since doing that. I didn't do the top of the engine, but did do the front lower than the middle, to get the bracket that holds whatever is in in the center of the crank pulley, and the block behind the PS reservoir and pump.
I filled up with 89 octane (started with half a tank of 91, but 91 at the station was 3.89 but 89 was 3.27) and drove half a tank down on that (160 miles on the interstate and a few around town trips). I have to make another longer interstate drive, so I filled up with 91 octane (I always run 91 unless testing something, or this last tank). Within 5 miles of leaving the gas station I feel the car start to stumble and buck when trying to maintain speed, a little hesitation giving it a little throttle, and serious bucking when WOT. Shakes at an idle.
I checked for codes and got a p0306 so I swapped the coil from 6 to 5. I still have the issue, but when I check codes this time (after clearing them) I now get a 304, 305, 306. CEL is NOT on, and it is not bad enough to be blinking, but I assume they are pending and once enough are detected it will trigger the CEL? I haven't gotten the "random misfire" code I have gotten it on moving cylinders every time I check codes and clear them.
Will bad fuel or fuel filter show up like this? anything else that would cause misfires on two different banks and different each time I drive it?
120k on the engine, unknown on the fuel filter, 10k on Motorcraft 32PM plugs, no oil in the plug wells or the coils, boots look solid/new with die-electric grease at the plug end and the seal to the bore. Car has been running decently, I have been trying to track down an intermittent P0174 and it seems to possible have a sucking loud leak that I cannot find.
I think the P0174 is causing it to never go fully ready (always have a P1000) and I of course this is when I have to get it past emissions, but need to get it running better to be able to focus back on the p0174.
I filled up with 89 octane (started with half a tank of 91, but 91 at the station was 3.89 but 89 was 3.27) and drove half a tank down on that (160 miles on the interstate and a few around town trips). I have to make another longer interstate drive, so I filled up with 91 octane (I always run 91 unless testing something, or this last tank). Within 5 miles of leaving the gas station I feel the car start to stumble and buck when trying to maintain speed, a little hesitation giving it a little throttle, and serious bucking when WOT. Shakes at an idle.
I checked for codes and got a p0306 so I swapped the coil from 6 to 5. I still have the issue, but when I check codes this time (after clearing them) I now get a 304, 305, 306. CEL is NOT on, and it is not bad enough to be blinking, but I assume they are pending and once enough are detected it will trigger the CEL? I haven't gotten the "random misfire" code I have gotten it on moving cylinders every time I check codes and clear them.
Will bad fuel or fuel filter show up like this? anything else that would cause misfires on two different banks and different each time I drive it?
120k on the engine, unknown on the fuel filter, 10k on Motorcraft 32PM plugs, no oil in the plug wells or the coils, boots look solid/new with die-electric grease at the plug end and the seal to the bore. Car has been running decently, I have been trying to track down an intermittent P0174 and it seems to possible have a sucking loud leak that I cannot find.
I think the P0174 is causing it to never go fully ready (always have a P1000) and I of course this is when I have to get it past emissions, but need to get it running better to be able to focus back on the p0174.
) until the misfire stopped. In my case it was the very last cop. 