[Riker]

Can anyone point out, with pictures, where the vacuum line that drops into the intake manifold and specifically where to get the can's straw in? Is there an easy tap?

I want to use CRC intake valve cleaner before my next oil change. I have done it the past two times by pulling off the intake duct before the throttle body and sneaking the straw in there barely, but it is a hassle holding that on hard enough and I don't have a hook straw to sneak in there.

When I took the whole duct off, the engine bogged a ton (without me spraying). I figured that was because the MAF sensor in the duct was saying there is no more air flow and it was getting screwed up. Maybe I should have given it more time? Either way, I figure the vacuum line method is much cleaner, and is even on the shop instructions for CRC intake cleaner.

Much appreciated!!!

[6spdhyperblue]

I’d pour into the one that connects to pcv. Disconnect the bottom connector so it’ll pour in right behind the tb

[Riker]

If I disconnect the PCV hose on the intake manifold, wouldn't the lose hose be blowing out what ever oil/particulates it is intended to cycle back into the intake manifold?

[6spdhyperblue]

For 5min while doing maintenance? Don’t leave like that. You have to reconnect it when you’re done

[Riker]

Ha no shit, I wasn't saying to leave it undone. I am saying for the 5-10 min it is disconnected, it will be spraying out particulates that it usually dumps back into the intake manifold.

Even if I used the PVC one, I would still need some pics or diagrams to make to use the correct one in that case as well.

However, I would rather do what the instructions for the product says which is to use a vacuum line.

[6spdhyperblue]

Then use the one next to the driver shock tower and under the ac line. That hose connects to the manifold

[Whocares05050]

Younare wasting your time... wont do much with direct injection.

[Riker]

@6spdhyperblue

I am going to take a picture of what I think you are referring to in my engine bay once I have time. I would definitely appreciate the confirmation/help!


@Whocares05050

The cleaner is specifically meant for direct injection. The fact there is no port injection of the fuel to run over the intake valves to clean them off means you need to clean them.

Some people do catch cans which I am not doing to avoid arguing with dealers/GM on warranty claims. Even if arbitration would force GM to prove the can caused a failure, it still means I would have to go through that whole mess.

I don't want to wait till the carbon build up is so bad that I get issues later and need a walnut blasting or other tear-down service.

So I am going with a regular cleaning with CRC GDI intake cleaner which has been used on tons of others DI-only engines and does combat the build up quite well.

[Whocares05050]

Use a bore scope before and after. It wont do anything. You are wasting your time and money. I have witnessed countless ones done and its snake oil. Catch can or walnut blasting are the only real ways to clean them.

I have a catch can myself, and it litterally takes 2 minutes to remove. Its held on by 2 bolts. It takes more time filling yhe gas tank....

Originally Posted by Riker

@6spdhyperblue

I am going to take a picture of what I think you are referring to in my engine bay once I have time. I would definitely appreciate the confirmation/help!


@Whocares05050

The cleaner is specifically meant for direct injection. The fact there is no port injection of the fuel to run over the intake valves to clean them off means you need to clean them.

Some people do catch cans which I am not doing to avoid arguing with dealers/GM on warranty claims. Even if arbitration would force GM to prove the can caused a failure, it still means I would have to go through that whole mess.

I don't want to wait till the carbon build up is so bad that I get issues later and need a walnut blasting or other tear-down service.

So I am going with a regular cleaning with CRC GDI intake cleaner which has been used on tons of others DI-only engines and does combat the build up quite well.

[protovack]

I was under the impression that you had to actually get those deposits out of your engine by using an abrasive and suctioning the debris out through the intake manifold, with the valves closed. I was told never use those cleaner products because they just cause the deposits to break off and get sucked into your combustion chamber leading to scoring of metal surfaces.

[Riker]

From what I have read and seen, you should use the cleaner before every oil changes so you are removing very minor deposits. I heard the bad thing to do is use the cleaner for the first time after 60k+ miles as you are likely to have very large and very cooked/hard deposits.

As far as catch cans, they only prolong the inevitable. I rather be actively cleaning periodically than just filtering. No catch can is stopping 100% of deposits. I have seen borescopes before/afters that clearly show reduction in deposits.

https://youtu.be/48JSlXlvMC0?t=552

That is timestamped at 9:12. Befores and afters of each intake valve. That is clearly having a large effect.