[motorhead]

Originally Posted by enzia35

I've heard it called the Italian tune-up.

[Bigdog9586]

Originally Posted by Bad Anvil Garage

I wouldn't run Sea Foam through my engine.... evidence of its effects are sketchy at best. Not worth the risk to sensors, etc. for me. Just change your oil regularly and use 93 octane.

Isn’t that why GM recommends the top tier gas?

[motorhead]

Seafoam is pretty mucha joke. It makes your car smoke so you are made to believe that something is happening. I have a family member that works at a dealership as a mechanic. He said it never fails wit GDI motors. They have him do some type of chemical cleaning that never works only to have the customer come back to have the top of the motor torn down for a manual cleaning. GDI motors suck. I dont care what anyone says.

[Need4Camaro]

Originally Posted by motorhead

Seafoam is pretty mucha joke. It makes your car smoke so you are made to believe that something is happening. I have a family member that works at a dealership as a mechanic. He said it never fails wit GDI motors. They have him do some type of chemical cleaning that never works only to have the customer come back to have the top of the motor torn down for a manual cleaning. GDI motors suck. I dont care what anyone says.

I have to disagree... I've seafoamed several non D.I. fuel injected cars and Seafoamed both motors that were babied and oil changed frequently and seafoamed cars that were driven to the edge... the cars that were driven to the edge left plumes of smoke so thick it literally fogged up the entire street to 0 Visibility, where as the cars that were babied and overly maintained were lucky to see a few fumes come out... and in both cases I definately felt a improvement in responsiveness...its almost like doing a tuneup. it's doing more than just producing smoke.

Now how dangerous it is to sensors? It's more so the crap that it pulls out the motor thats dangerous to them, so if your motor has alot of carbon build up on it, you risk fowling out some sensors..I've yet to do this fortunately..but it is possible.

[ShaBoom]

Is there any evidence of a carbon build up issue on the intake valves of the LT1?
All I can find is people talking about the possibility of this referencing other makes of cars.
If it isn't broken- don't fix it. Just enjoy the car, there's nothing wrong with it.
Put some stripes on the fenders or something. You'll feel better.

[glenB]

You can use Seafoam but, GM has a top end cleaner that is top notch. What is it..... Techron.

The trick to making sure it works is employing properly.

You don't want to use the brake hose, too big. Source a 5/16 sized nipple. You can use PCV nipple and size it down or restrict it. It's going to take 2 people, 1 at the can, 1 to operate the throttle. Introduce a small about to coat the intake tract. Then as you get down to about half the can start flooding it until it stalls. If done right it should have sucked down about half. Let it set and soak for about 30 mins. and then fire it up and blow it out. If there's any in the can just put it in the gas tank.

[Mr. Wyndham]

Originally Posted by glenB

You can use Seafoam but, GM has a top end cleaner that is top notch. What is it..... Techron.

The trick to making sure it works is employing properly.

You don't want to use the brake hose, too big. Source a 5/16 sized nipple. You can use PCV nipple and size it down or restrict it. It's going to take 2 people, 1 at the can, 1 to operate the throttle. Introduce a small about to coat the intake tract. Then as you get down to about half the can start flooding it until it stalls. If done right it should have sucked down about half. Let it set and soak for about 30 mins. and then fire it up and blow it out. If there's any in the can just put it in the gas tank.

Are you sure it's called Techron? Like the stuff you can buy in the auto parts store by Chevron?

[glenB]

Originally Posted by Mr. Wyndham

Are you sure it's called Techron? Like the stuff you can buy in the auto parts store by Chevron?

Was told by my parts guy that the GM Top End Cleaner was rebranded Trechron when he didn't have any. Hes been my go to guy for 30 some years. BG 44K also works good.

[CruzySS]

Originally Posted by Lerch98

Is carbon build up on the valves a product of not using a catch can and inhaling all those thick hydrocarbons into the the engine?

A catch can will help the intake and valve build up

[motorhead]

Originally Posted by glenB

Was told by my parts guy that the GM Top End Cleaner was rebranded Trechron when he didn't have any. Hes been my go to guy for 30 some years. BG 44K also works good.

Chevron Techron is for in the fuel tank. You're supposed to use it if top tier fuel isnt available. It isnt used to perform top half intake decarbonizing.
X66p is the top half cleaner that GM uses and its very different than Techron. you dont put x66p in your tank and you dont put Techron in your intake. Two different chemicals for two different functions.

[motorhead]

Originally Posted by CruzySS

A catch can will help the intake and valve build up

Many studies are proofing that catch cans arent doing much to solve this issue, and there are only a few brands out of the many that do anything at all. People keep saying about fuel not hitting the back of the valves in GDI motors. That's correct, but the coking and carbon build up comes from more than the PCV system. Valve overlap allowing some combustion gases to hit the back of the valves for one and valve seal leaks to name just two. A catch can will do nothing for either.

[KingLT1]

Originally Posted by ShaBoom

Is there any evidence of a carbon build up issue on the intake valves of the LT1?
All I can find is people talking about the possibility of this referencing other makes of cars.
If it isn't broken- don't fix it. Just enjoy the car, there's nothing wrong with it.
Put some stripes on the fenders or something. You'll feel better.

Yes there is plenty of evidence. There are other sections in this forum that have more technical discussions on this subject.

GDI engines are notorious for oil coking on the back side of the valves due to blow by from the PCV system. The intake manifold, intake ports on the heads, along with valves get coated with oil. Since direct injection sprays fuel directly into the combustion chamber, fuel does not make contact with the intake ports or valves. I use a chemical spray from CRC through the throttle body with the engine running. You have to disconnect the maf so the ECM reverts to speed density and will run without the intake hose connected. A CEL will popup but can be easily cleared.

Seems to have made a difference on my 2012 GMC Terrain GDI 2.4. 80k miles and going strong. First time I cleaned it around 50k miles it smoked like crazy out the exhaust. The last couple times not so much.

[FrostySS]

Originally Posted by Bad Anvil Garage

I wouldn't run Sea Foam through my engine.... evidence of its effects are sketchy at best. Not worth the risk to sensors, etc. for me. Just change your oil regularly and use 93 octane.

Completely irrelevant when talking about DI engines and how they operate. Obviously changing oil regularly and using 93 octane should be done anyway but it won't magically make the carbon build up stop.

[Mr. Wyndham]

Originally Posted by FrostySS

Completely irrelevant when talking about DI engines and how they operate. Obviously changing oil regularly and using 93 octane should be done anyway but it won't magically make the carbon build up stop.

True - it won't...yet, I don't think it's fair to say its irrelevant, either. There are processes that can be done (albeit invasive) 80 - 100,000 miles down the road to return the valves & seats to new. So for many people, just leaving it alone is what you do.