Went to work the other day. All was fine. It was a wet drive in. When I went to come home the truck started real ugly... Drove home about 30 miles. All the way back it was nasty.. Check Engine Light came on...

So I checked my codes and up comes a 305 and 174.
So far I checked all the plugs for issues.. There were none but replaced them anyways. Pulled, both coils, the right was running a little off spec so replaced it tonite. Going out to clean my MAF with a qtip and alcohol.

Not sure what to check next. Guess I could change the fule filter in the morning... Any Suggestions?

Thanks In Advance

 

P0174 is the driver's side O2 sensor telling you that the left side of the engine is running lean, P0305 is a misfire on #5 cylinder (front driver's side).

If you've checked the coil packs and replaced the plugs, you may have a bad plug wire (common sense tells me that a bad plug wire would cause a "running too rich" code, but you never know) or a plugged (or defective) injector on that particular cylinder.

 

it thinks its running lean because the O2 sesor is seeing all the unburnt oxygen going by it.

its on oxygen sensor not a hydrocarbon sensor. thats why it shows lean on a misfire.

i would look into coil, plug, wire for number 5 cyl.

 

I had the same problem about two months ago; replaced pcv with hose and got it fixed.

Marcos

 

Well here is an update....
Replaced all plugs...
No affect, P305/174 still there

Checked passanger side coil, a little off spec so replaced it.
No Change, P305/174 still there

Replaced all plug wires today. Have not checked yet as I am replacing PCV valve as well. Need to pick up part after hockey game.

If all this has no affect, I will pull No 5 injector and replace. I think it can be pulled without removing intake planum (Service Manual say remove for replacing all). Will update tonite after I replace PCV...

Think that if that is not it then check O2 sensors, but not get O2 code....

Any Thoughts?

 

Problem solved. Faulty Injector.

Diagnosed with Mechanics Stethascope, could here no action from injector. Replaced with NAPA injector.

Did not remove Planum.

- Denergized fuel system and ran truck till it died.
- Removed air filter and MAF housing
- Unbolted power steering resevoir
- Unbolted Driver side fuel rail
- removed no 5 injector
- used light oil on o rings of new injector and replaced.
- Only tough part is getting all the injectors reseated with all the hoses still in place.

Be patient it will go back in.

Total time to diagnose and replace was less than 4 hours. Truck runs like new.

Complete list of New parts includes
new Plugs, Plug Wires, and Passenger side coil
New PCV valve, new fuel filter
New Injector.

New Tools
Mechanic Stethoscope
And best of all New OBDII Code Reader....

Thanks for all the great threads and comments..