98 Avalon codes 302-304-306 and 300

3.0 V6 fed. 137 K mileage
Also lean and rich bank 1 codes 171-172
Cleared codes and now has low count of ramdom miss on all cylinders on missfire reading.
Engine running rough and miss at idle and low speeds and slow take off.
Runs good at higher rpm.
Any help or ideas.
Thanks

Lets start with the basics, when was the last tune-up and what did it include... plugs, wires, coils?

Lets start with the basics, when was the last tune-up and what did it include... plugs, wires, coils?

Thanks
That sounds like a winner to me.
I just noticed it is 237K instead of 137K.
Will also check compression.

Thanks
That sounds like a winner to me.
I just noticed it is 237K instead of 137K.
Will also check compression.

PULLED PLUGS AND RAN COMPRESSION TEST.

Found problem.
Rear cylinders at 210 lbs and front cylinders at 110 lbs.
Front camshaft must be out of time or belt slipped.

That extra 100k will make a difference! Good idea to check the compression. Let us know what you find as the cause for the different readings!