2007 tundra 5.7 misfire on calendar 6

Thanks for making the new guy feel welcome. I have a 2011 tundra crewmax that I like better than any truck I have ever owned. ( always fords ) I have purchased a 2007 that is not nearly as nice as 2011 to use for a work truck. I purchased the truck with a miss in the engine. I am getting the code for a misfire on cylinder 6 and random misfires. I have replaced the plugs, cylinder 6 coil pack, fuel injector, ECM module and cut all the tape off of the wiring harness to verify that I have good conductors. After all of this, i am back where i started. The cylinder 6 injector does not pulse ( I am checking with a stethoscope). I have checked the resistance on the injectors on bank 2 and they are 12.4 ohms. I am not a mechanic and i do not know what to do next. My work truck idea seems to have turned into a contest. I would appreciate any guidance. Thanks in advance!

 

You haven’t mentioned doing a compression test, so if you haven’t done one I’d do that next.

I know you’re saying the #6 injector isn’t firing, but keep in mind the ECM will stop firing the injector when a miss-fire is detected and a fault is active. This is to protect the cats from melt-down from raw, unburnt fuel.

 

Oh, what engine in your ‘07? 4.0L V6?

 

This^^^^^

 

Thanks for the reply! The 2007 tundra has a 5.7 liter engine with 126K miles. I failed to mention the compression check which was app. 110. I felt that was in the range am I ok?

 

I should have also included that the compression check was done when engine was not up to temperature. I am going to take some more time with that and check the other cylinders for comparison. I am afraid this is too low and I do not know how much the will change when the engine is at temperature.

 

110 seems low, of the top of my head, I’m not really sure how low for this engine. Great idea to compare with the other cylinders. You don’t want to see more than 10% difference.

Good to hear it’s not the 4.0L V6, the early models have become known for head gasket failures that cause a cold-start miss-fire due to coolant leakage into the cylinder.

 

Compression is low at 110. Minimum is 145psi, max is 189psi...... Here is a link to some reference....
https://www.engine-specs.net/toyota/3ur-fe.html