PULLING MY HAIR OVER A P0301 code!!

[j91z28d1]

3% seems close enough for pump e5. so that's good.

 

[opfor2]

Another curiosity is that the OBD port is hot sometimes. Even with the truck off, I can sometimes connect to the OBD reader and the truck although, as it's off, there aren't any readings obviously. Unless I am truly losing my mind over this.
The 8th digit is a 0

If you have issues with your OBD port being dead check fuse 53 in the engine compartment.

 

[57210chevy]

This whole thing has me regretting buying this PPV. I've never had a simple misfire not be fixed with a plug alone, in some cases the wire, and in rare cases the coil.

It's chewing through gas like it was free. I can't seem to locate the cause of the misfire. It smells HEAVILY of raw fuel and shakes like it's going through withdrawals.

Here are new details I have. The codes are now:
P0301 misfire #1 cylinder
P0446 EVAP System Vent Control
P0461 Fuel Level Sensor "A" Circuit Range/Performance
P0463 Fuel Sensor "A" Circuit High

The odd thing is that looking at recorded 'live' data from the OBD scanner, I'm not seeing a misfire on #1, but I am seeing misfires on 2, 3, 5, and 7. Sometimes 3. All plugs and wires have been changed on 1, 3, 5, 7, and 2. (NGK G-Power plugs and generic 10.5mm silicone wires)

I cleared the codes, restarted the truck and THE SECOND the CEL comes on, I hear a noise coming from the rear of the truck (thinking it might be the Canister Purge Valve making that whine.) I'm not sure at this point. It is a kind of hum. I can re-create it by clearing the codes and starting the truck up again and waiting less than 30 seconds.

I have also begun to think that it might be a clogged PCV system that is causing the misfire, along with perhaps the Canister Purge Solenoid under the hood.
What do y'all think?? Could it be a partially clogged fuel filter?

I don't want to just throw a flurry of parts at this, but I'm getting desperate enough to start just throwing parts at this thing. And the 'coincidental' fuel gauge failure isn't helping as my wife is having to still drive this thing 30 miles a day to/from work and I troubleshoot once It's cooled down.

When I checked the oil level a couple of weeks ago before this all began, it was just oil, no milkshake.

I also put about 1.5 cups worth of acetone in the tank to 'superclean' the injectors.

i did this acetone trick before smoked my fuel regulator on a 04 silverado there is a vacuum line attached to it that was dumping fuel into the intake theres your problem pull the vac line see the fuel replace the regulator and unless the fuel is dumped see it fail again ask how i know

 

[Fless]

i did this acetone trick before smoked my fuel regulator on a 04 silverado there is a vacuum line attached to it that was dumping fuel into the intake theres your problem pull the vac line see the fuel replace the regulator and unless the fuel is dumped see it fail again ask how i know

The OP's vehicle is a much later model, without the vacuum fuel pressure regulator. It would be good to keep these recommendations applicable to the vehicle in question.

 

[ReaperHWK]

All this and you haven’t changed the injectors yet? Or did I miss that?

 

[PBandJs_PPV]

i did this acetone trick before smoked my fuel regulator on a 04 silverado there is a vacuum line attached to it that was dumping fuel into the intake theres your problem pull the vac line see the fuel replace the regulator and unless the fuel is dumped see it fail again ask how i know

The acetone destroyed the fuel regulator?

 

[PBandJs_PPV]

All this and you haven’t changed the injectors yet? Or did I miss that?

I haven't changed them because the odds of multiple simultaneous injector failures is so low.

 

[PBandJs_PPV]

Out of curiosity, is it bad to rev the engine while in P or N on these trucks?

 

[PBandJs_PPV]

Okay, just got worse. I took her for a quick test drive and she started smoking just as I pulled back up my street. Popped the hood and found this.

Is this a line that leads to the heater core?

 

[Tonyv__]

Sigh... I was dreading having to take the cover off, but in reality, I will KNOW either way at that point.
I'll at least remove the question mark in my head.

I chased my misfire for months. (It was my work vehicle so I couldn’t really spare the time to put her down for days or send it to the shop). I finally decided to pull the valve covers and could physically feel the difference on the rocker of the cylinder in question. At this point I knew it was mechanical.

It’s a pain in the Ass but it might answer some questions sooner than later.