3RZ FE Misfire Problems, could it be burnt valves?

Hello all, I'm new to this forum and would appreciate any help..

I have a 2002 Tacoma 4x4 2.7L Manual tranny. It has 287k on it. As far as I know its never had a valve adjustment. I bought it at 135k and its been a dream.

A few days ago my CEL flashes for 5 seconds then is solid (CEL is on usually for EVAP code) The it happens again, seeming to still drive fine. Idles a bit rough when it gets up to temp AND A dollar bill gets sucked into tailpipe every few seconds or so.

My Codes:
P0300
P0303
P1300
P1310

Other things I did recently:
Cleaned MAF
Replaced Muffler, pipe and O2 sensor
Removed second catalytic converter
Ran Cataclean to get inspection (first one must be plugged, its a CALI car i believe)
Contact cleaned connectors on Coil Packs
Replaced Coil Packs on cylinders 1 and 3
Replaced Spark Plugs

Things I noticed:

When pulling old coil packs, 1 and 3 had dry rotted boots from heat I presume and 2 and 4 looked absolutely fine. 1 and 3 plug tubes also looked rusty from heat or something.

I just dropped some seafoam injector cleaner in the tank as well as some seafoam engine cleaner in the oil. Gonna drive it 100 miles or so and see what it does. CEL flashes intermittently or when I accelerate hard, not its not that often that it flashes.


From what I've read, this could be a sticky valve issue or Burnt Valves... What should I do? Truck runs great seemingly aside from a slight misfire and I don't want to damage it anymore. Thanks for any help or insight you can provide!

-A

 

Welcome aboard new member
Driving with a flashing CEL is a
BIG NO NO.

 

Welcome to TW!

 

When changing spark plugs a compression test should be performed.
And a leak down test if the compression test dictates.
Burnt tubes and boots indicate high temp from lean A/F ratio.
Possibly just vac line leaks but chopping off cat#2 ain't helping exhaust backflow.
Time for thorough diagnostics by knowledgeable mechanic.

 

Welcome!

 

welcome from SE VA! Enjoy the journey!