GM used to have some really good fuel system cleaner, but then had to reformulate it due to it being too toxic to the environment. That being said you don't need to clean out the injectors every 30k, they are selling you $180 worth of service you don't need, but thats how they make their money.

 

agreed

 

Direct injection can allow varnish to deposit very very very quickly on intake valves. Like poorly tuned 1960's carburerator quick.

If you aren't seeing smoke come out, chances are it got sucked into your crankcase or it is sitting somwhere, never going into the cylinder.

You will have to pull it out of the car from a vac port right on the intake manifold.


Also do not bother putting injector cleaner in your tank. That cleaner isn't going to clean anything pump fuel at 200 bar isn't going to clean :]

But EVERYONE here should be doing a DIY port cleaner BEFORE every oil change. Meaning just before your oil change throw some cleaner in there, get it smoking nice and good like and then change the oil.

Please observe the 2.0 FSI VW motor, which is very similar to GM's design.

http://forums.vwvortex.com/zerothrea...ostid=63888895

Oh but I do want to point out the LNF won't cake up as badly so fast as the POS VW motor but DI does not allow any mitigation of caking due to no fuel passing the valve or port.

 

How exactly is the pressure effecting the ability of a cleaner to dissolve varnish?

 

You'll get that if you run it all through without getting a good shot of it in at the end. So you probably just didn't have much still in the engine when you went back and started it. Also, the big white cloud of smoke you get is really just the seafoam and it's not a massive amount of carbon deposits that people tend to believe. Unless you were experiencing serious carbon issues, what you did is likely plenty.

 

No I wouldn't, those cleaners are made to clean valves intake passages etc.. DI puts it in to the cylinder not going to do much other than clean the injector, a can of 44k is what id recommend and a cleaner that goes through a vacuum port would probably help. Cleaning the MAF isn’t a bad idea but as stated before you can do much cheaper. Just pull the MAF out spray the through it same direction as air flow and don’t touch the resistors.

 

^^ totally not on topic, but I love your user name! lol

 

Yah I would love to see some pics and/or how-to aswell as I will be changing my oil soon and this is something I want to do.