[WINSTON44]

MY 2001 TUNDRA 4.7 has never missed a beat until last week. code P0301 cylinder 1 misfire detected, then secondary
DTCs P0300 random misfire detected. P0306 cylinder 6 misfire detected, pointing to ignition coil. I replaced all the coils
and the engine is the same as before doing anything. What is the fix?

 

[cheapskate]

I cant help directly but read this. Specifically the last 2 posts.

Difficult starting, rough idle below 1k, tried everything

The manual says this about the p0300 code: CIRCUIT DESCRIPTION When a misfire occurs in the engine, hydrocarbons (HC) enter the exhaust in high concentrations. If this HC concentration is high enough, there could be an increase in exhaust emission levels. High concentrations of HC can also...

www.tundrasolutions.com

Type your code, P0301 into the search box at the top of the page. Thats where this one came from. See if any other threads have some suggestions to help you find a solution.

 

[gecj77]

Quick answer, remove and have all eight of you fuel injectors get flow tested and professionally cleaned. I went through the same issues and now my 4.7 runs and pulls like its brand new. The injector specialist found that all my injector flow tests were low and i had one dead one as well. I had 200k on the motor and I still cant believe what and improvement it made. Here is the shop where i mailed my injectors too. Mr Injector
Good luck.

 

[Professional Hand Model]

A nice upgrade is the 12 Hole Injectors by Denso. They can be purchased from Oside Tiger which is where mine are from. They were about $300 for 8 rebuilt Injectors a few years ago. They do slightly improve the engine dynamics like throttle response. Main improvement on my 2002 is that the transmission shifts better. Holds gears longer and eliminates that lazy down shift on a deceleration. Unexpected benefits from Injectors I know. MPG’s saw no improvement for me.

OP what did you end up doing?