50k miles valve cleaning exploration time

[The Fed]

no I'm saying you don't know the process

So tell me, if you know. All I can say is, that's the way they used to do it. As I recall, it was the driver who climbed up the ladder and added them before he closed the tanker's lid. Perhaps it's changed.

 

[cldlhd]

LOL you might be right about the valves, but your wrong if you think you don't need top tier fuel.

https://s3.amazonaws.com/associationcommunicationfiles/PDF/Fuel-Quality-Full-Report-FINAL-1.pdf

I never said there was no benefit to top tier fuel but having read most of that report they tested on a port injected engine not direct injected so the difference in regards to the intake valves might not apply. I assume the main benefit for a DI engine would be the injector and the combustion chamber. I usually use top tier but occasionally if I'm at wawa grabbing a coffee I'll get it there.

 

[drrck]

Decent read on additive packages.

http://blogs.platts.com/2010/08/23/unbranded_vs_br/

 

[GLoBaLReBeL]

If that's true, someone needs to create a cheap additive package that can be added to unbranded gas to get the same effect.

 

[PLF8593]

I never said there was no benefit to top tier fuel but having read most of that report they tested on a port injected engine not direct injected so the difference in regards to the intake valves might not apply. I assume the main benefit for a DI engine would be the injector and the combustion chamber. I usually use top tier but occasionally if I'm at wawa grabbing a coffee I'll get it there.

I work at Wawa and would/do not trust their fuel, and say the same to other car enthusiasts. They're the only gas station i've ever seen in Jersey that doesnt even have 93, they have 92. In my opinion, that says something, and i dont trust it.

 

[cldlhd]

The wawas near me in pa have 93 but just filled up today with the ol' top tier Shell. My mechanic buddy and I were discussing this issue at the bar a little while ago and he say the class he took said top tier would help even with the intake valves on a DI engine as the fuel starts to inject just before the intake valve closes. Not sure if its true or for which engines but hey

 

[PLF8593]

Its defs not true for most DI engines.

 

[The Fed]

I thought fuel wasn't injected until the piston was near the top of its stroke. By then the valves would be closed. We talking high RPM where there's probably some valve overlap?

 

[BravoMike]

 

[GTIJames707]

I thought fuel wasn't injected until the piston was near the top of its stroke. By then the valves would be closed. We talking high RPM where there's probably some valve overlap?

in a direct injected vehicle fuel can be injected during the intake stroke (piston moving downward, intake valve open) this is called a homogenous charge and is used during acceleration/heavy load situations.
Fuel can also be injected during different stages of the compression stroke, (upward, closed) called a stratified charge and this fuel timing is used during cruising on the freeway, light loads, ect. The stratified charge is ultra lean, and very efficient.

But it's not the valve's being closed/open, or whatever that creates the possibility of carbon buildup on the backs of the valve WHILE THE VEHICLE IS RUNNING. Once you shut your car off there's going to be a little bit of combustion gasses floating around and some of the valves will be closed, opened, half way, whatever, and those combustion gasses accumulate wherever they land. Port fuel injection just washed that shit away during next driving cycle (or, washed some of it) where as DI never gets that opportunity.

the humble mechanic has a very good couple of videos on youtube explaining this, and in my automotive school it was a hot topic for discussion. I went to Butte College Automotive in Chico CA and now that I'm working side by side with kids who paid 10x as much for an "education" at UTI, I couldn't be happier with the training I received at butte college. I would strongly recommend the program for anyone in the area even remotely interested in better understanding any or all areas of cars. You don't need to go all in, like with UTI, you can take just engine performance, or just alternative fuels, or just brakes and chassis. very cheap, super quality.

But the humble mechanic and paul from DAP both have youtube videos with great theory's about why carbon build up is such a huge issue. I listed above my favorite of all the theories.

 

[BravoMike]

GTIJames, thanks for all of the info. Variable timing on the injectors! I had no idea.

HumbleMechanic is a great channel to watch; great recommendation!

 

[cldlhd]

in a direct injected vehicle fuel can be injected during the intake stroke (piston moving downward, intake valve open) this is called a homogenous charge and is used during acceleration/heavy load situations.
Fuel can also be injected during different stages of the compression stroke, (upward, closed) called a stratified charge and this fuel timing is used during cruising on the freeway, light loads, ect. The stratified charge is ultra lean, and very efficient.

But it's not the valve's being closed/open, or whatever that creates the possibility of carbon buildup on the backs of the valve WHILE THE VEHICLE IS RUNNING. Once you shut your car off there's going to be a little bit of combustion gasses floating around and some of the valves will be closed, opened, half way, whatever, and those combustion gasses accumulate wherever they land. Port fuel injection just washed that shit away during next driving cycle (or, washed some of it) where as DI never gets that opportunity.

the humble mechanic has a very good couple of videos on youtube explaining this, and in my automotive school it was a hot topic for discussion. I went to Butte College Automotive in Chico CA and now that I'm working side by side with kids who paid 10x as much for an "education" at UTI, I couldn't be happier with the training I received at butte college. I would strongly recommend the program for anyone in the area even remotely interested in better understanding any or all areas of cars. You don't need to go all in, like with UTI, you can take just engine performance, or just alternative fuels, or just brakes and chassis. very cheap, super quality.

But the humble mechanic and paul from DAP both have youtube videos with great theory's about why carbon build up is such a huge issue. I listed above my favorite of all the theories.

So maybe my mechanic friend wasn't totally off base.

 

[BigDan]

The wawas near me in pa have 93 but just filled up today with the ol' top tier Shell. My mechanic buddy and I were discussing this issue at the bar a little while ago and he say the class he took said top tier would help even with the intake valves on a DI engine as the fuel starts to inject just before the intake valve closes. Not sure if its true or for which engines but hey

WHERE?

 

[cldlhd]

WHERE?

Lower Bucks in the Fairless Hills /Levittown area . Stopping for a coffee in a bit I'll double check.

 

[cldlhd]

Anyone out here with a catch can on a gen 3 that got anything significant out of it?