Engine Fogging; Vacuum vs. TB

[V1]

I don't know of any other methods besides either pouring/spraying the product into a vacuum line or through the throttle body (or any combination thereof). What are some considerations that must be taken?

Which is more effective in terms of product distribution? How can I make sure the product reaches every cylinder as equally as possible? My logic says that if you apply through the TB, you have a better chance at that. Especially if you aim the nozzle in varying directions. I know that on my Mazda6 3.0L the rear cylinder bank gets more of the PCV and EGR overflow. So perhaps fogging through the PCV or brake booster would be less effective on my car.

Besides filtration issues, is there any harm in fogging through a naked TB? In other words, remove all pre-TB plumbing, start the engine, and spray directly at the TB plate. Is this a good way to also clean the TB? Any chance of harm to an electronic TB?

Finally, if a car is MAF-equipped, is it safer to disconnect the MAF before fogging? I'm concerned that the computer might run things too lean.

 

[Quest]

IMHO the best way to fog an EFI engine is to:

(a)take off all the spark plugs and spray the conbustion chamber with fogging spray

(2)disable/ground all your ignition to keep the spark plugs from sparking. Also disable the fuel pump (of possible, relief the fuel rail pressure also)

(3)with throttle closed, pull a vacuum plug off of the intake manifold and stick the fogging spray tube into it.

(4)ask someone to help you crank over your engine. While cranking, spray some fogging oil into your intake manifold so as to coat the intake valve stems, seats, and contact surface (lips).


--Do not spray any fogging oil onto plastic bodied electronic sensors, MAF sensors, etc. Also: do not get any fogging oil onto rubber vacuum hoses, PCV hoses, etc.

 

[V1]

Fair enough. Suppose one went ahead with your procedure. Now consider this:

You have a V6 which requires complete removal of the IM to access the rear spark plugs. Would it be acceptable to spray fogging oil directly down the intake ports?

Your method would require a lot of extra work on this kind of an engine. Is it worth it if you want new spark plugs at the end of it all? Basically, remove and replace the IM two times!

 

[gtx510]

I doubt your Mazda will run with the MAFS disconnected. It might but it'll be in limpmode.

Ground an ignition system?

You can accomplish the same thing by cranking the engine and spraying into the throttle body.....

Oil? That's what you're trying to get rid of. Don't use oil...

And try some CRC MAFS Cleaner.