Cleaning Intake Manifold and Fuel Rail/Injectors questions
 

I currently have the fuel rail/injectors and intake manifold out of the car and am wanting to do a good cleaning on them.

What is the best way to accomplish this that is safe for all components?

Would also like to clean up as much around th motor as I can while I am there.

Thanks.

Cheers

Brake cleaner (I pick the red nonflammable kind) works really well, but isn't good to run in the engine, so clean it all out thoroughly. I collect it into a steel coffee can and reuse it to clean small parts. When it gets gross, turn it in for disposal (my county accepts household hazmat for free). It is carcinogenic so work with plenty of ventilation. The newer green version is highly flammable which worries me more...

Definitely keep it off your paint!

Ok is there any small parts built into the intake manifold I need to be careful of? The EGR and the other valve have been removed as I am replacing them.

Read a post where someone filled a sink up with degreaser and letting it soak for a few hours. But as its plastic I am worried of using anything harsh

The plastic parts for the intake should be designed to survive gas and oil and are pretty chemically resistant. Something like a tub of simple green degreaser in warm water should be fine. Just make sure it's good and dry before assembling it. Do be careful as simple green will etch/discolor any shiny aluminum pieces.

No built in sensors that I can recall. The throttle body and CCV valve unbolt and that would improve access to clean the inside

I have a neat tool for this. It's a pressurized fuel injection cleaner with an atomizer attachment that mounts in the intake boot, downstream of the MAF. You fill it with induction system cleaner, block the pedal to run the engine at about 1600rpm, so the throttle plate opens and let it run until the canister empties. Probably not as good as removing the manifold and cleaning it thoroughly, but it saves labor.

I bought it to decoke my kids direct-injection A4.

Interesting, never heard of it, I already have the parts off the car for another project so probably going to do it by hand.

I am planning on cleaning the injector o rings with a silicon spray and then using to it grease them up before re installing the rail

Not my video, but this is the tool I have.

https://www.youtube.com/watch?v=biM5-GW4CLQ

I heard to use Vaseline to grease the o ring never silicone spray/grease!!

Also if you want to clean the injectors get a 10ml syringe with plunger removed get a red spray straw and wrap one end with electrical tape, thread straw from the inside, insert injectors into back of syringe, attach red straw to can of compressed carb cleaner, find an old unwanted 12v power supply an attach to injectors terminals using alligator clips, plug power supply into a power strip with an on off switch, pressurize the system by pressing down on the can, turn power supply on and off while adding more cleaner, flip injectors over and repeat on both sides of all injectors. Note you will need new o rings and may have to cut. The old o rings to get a good seal on injectors.