The P0172 That Won't Go Away...

I removed the air filter and stuck my phone into the air box...this is the noise it's making...sounds like it's missing, but I dont have any misfire codes, only the P0172.

https://streamable.com/jr9c1

 

If the motor isnt mechanically sound you will be wasting money and time trying to fix the un-fixable... when was the last time the valves were check/adjusted? Take the PCV valve out and shake it. It should rattle... this is a controlled air leak. Take the oil dipstick out and rub the oil on it between your fingers, does it feel any different than new fresh oil. Sniff the oil then taste a tiny tine drop of it, does it smell like gasoline?

I would put a vacuum gauge on the intake manifold and listen to the air box popping... does the vacuum gauge drop when it pops? If it does it sounds like an intake valve not sealing 100%. This could be from too little or no clearance on that valve or a broken or weak valve spring.

The other possibility is that the air ports that shroud the injectors are plugged. On the back of each cylinder head there are 2 vacuum ports that connect to a vacuum "Y". These are there for better fuel atomization. If/when you take the injectors out you will see the slot/port/groove in the injector bore towards the intake side of the head.

 

Check the “key” that is in the middle of the timing belt if its loose it can give you a gremlin

 

Bump

Ok so, i ended up taking it to another shop to get another set of eyes on it. Unfortunately the battery died and cleared the P0130, P0133, and P0172 codes, but I was able to get the P0172 to come back...they checked the timing and said Bank 2 lines up perfectly with respect to the crank but Bank 1 is off by what looks like half a tooth or so with respect to crank. He also said it looks like the heads may have been decked as well and that overmachining could have caused this...and also I have a Napa timing belt on there. I would think if it was the belt then both sides would be out of time?

Does this make sense? The head sits lower to the block and causes the cams to be off by 1/2 a tooth on that one side?

I'm quite confused...thanks for any help in advance!

 

Just changed alot of stuff and had this code pop. Had the entire intake off to replace knock sensor loom. The little vac hose on the fuel regulator seemed old, swapped; now my fuel trim is back to normal and everything seems fine. Just an idea.

 

This little vac hose, top end seemed loose. Maybe it's that simple.

 

Oops sorry, did not get to this post I guess.