P0301 troubleshooting and diagnosis

260xxx on the clock and I'm experiencing a minor to moderate shudder upon accelerating up an incline on pavement. It seems to shift into second or third and take off from there without incident.

Driveline U joints and carrier bearing replaced about 2.5 years and 60-70 thousand miles ago.

 

Have you checked them again?

 

When was the last time transmission fluid was changed

 

About three years ago. I checked the level about two months ago and it was a little high.

not yet, it's been stormy and the shudders just started within the last week - they're on the list for Monday when it's supposed to be dry.

 

Just got a bad shudder and flashing CEL at 50mph, and misfire on idle.

waited 5 hours (1a-5a) for a tow. AAA is terrible.

I'm thinking bad coil, heading to the shop to grab my computer, fingers crossed.

 

I've only got a P0301, i'm working on pulling the spark plug.

Any input?

 

I have now, everything seems solid in the drivetrain

 

Swap #1 plug with #3 plug.
Swap #1 coil with #2 coil.

See if the miss stays, or follows the plug or coil.

A P0301 won’t be cause by the transmission or u-joints.

 

Yeah, there was a shudder initially I couldn't place, the code popped up last night with a pronounced misfire. I'll follow your procedure when the suns up. Thank you.

 

I've found both valve cover gaskets to be leaking.

the #1 spark plug is "normal" and reeks of gasoline.

parts ordered.

 

Were the plug wells full of oil?

 

There's a noticeable amount in each but it's not dripping.