Does the sulfated ash (SA) level really matter for intake-valve deposits (IVD)?

[OilUzer]

Assuming true, high compression ratio engines should help with more heat.

 

[avi1777]

had a cts before and the short trips just killed it,cold start misfires u name it,had to move to premium and it went away.

 

[OilUzer]

Sounds like short trips are bad news all-around. From fuel dilution, wear ... and now increased ivd if this theory is true.

 

[avi1777]

ye its a complete disaster guarantee.

 

[OilUzer]

Maybe they can also play with the cooling system to keep the temperatures higher. Need some engine designer to answer. pros & cons, etc. You know more heat to reduce ivd but destroy something else.

 

[avi1777]

the only way to avoid ivds is going full electric-)

 

[avi1777]

but i have to say my tail pipes are completely dry after 4500miles with the ss,it wasn't the case with the previous magnatec and ecolite i used previously.maybe the low noack does matter.

 

[skrypj]

I ran a catch can on my Ecoboost. I could fill a 1 gallon windshield washer fluid jug in less than 10k miles. Most of it seemed to be oil but about 50% of it was water, fuel and some other nasty stuff that looked like yellow whipped cream.

I also sprayed the seafoam GDI cleaner every other oil change starting from 9000 miles.

My valves were very clean when I bore scoped them at 91k miles. Much cleaner than other Ecoboost valves i have seen pictures of.

my theory on the GDI cleaner is that, if you start it early enough and often enough, you are not giving the valves enough time to coke up to where chunks falling off is an issue. Sure, if you go spray it after 150k miles of crappy oil and 10k mile OCI’s then there could be an issue.

 

[ChrisD46]

I will argue that the sulfated ash (SA) level -- that is the metal content of an oil -- does not matter for intake valve deposits (IVD) in gasoline direct-injection engines.

The IVD is mostly composed of coked base oil with ash (metal) additives that doesn't evaporate. It also contains some exhaust particulates (from EGR) etc.

However, since the primary building block of the IVD is coked base oil, how much would the SA level really make a difference? The base oil makes roughly 80% of the oil, whereas the ash is only about 1%. Therefore, I will argue that since the IVD is mostly coked base oil, the ash level has a small effect.

In order to combat the IVD, the following all help:

(1) Higher-quality base oils, such as PAO and POE, or the poor-man's higher-quality base oils such Group III+ and GTL.
(2) More antioxidant to reduce the oil coking.
(3) More or better detergent and dispersant to keep things clean.
(4) More POE or AN to increase the solvency of the oil, which could loosen up some of the coked oil.

There doesn't seem to be any research on this other than a faulty Lubrizol field study that compared a superior (Euro IV) low-SAPS oil to an inferior (Euro III) full-SAPS oil, which obviously favored the Euro IV oil, regardless of the SAPS. Any thoughts?

*The approach I take to reduce IVD in my GDI engine :

1) Synthetic oil with low VII's (Valvoline Advance , QSUD , etc.)
2) Use Tier 1 gas
3) Use Fram Ultra oil filter
4) OCI with above mentioned oils of less than 5,000 miles / 4 months .
5) Use CRC Intake Valve Cleaner every 12,000 miles
6) Keep air filter and spark plugs clean and in good condition .
7) Keep PCV clean and operating properly.
8) Keep RPM's up and don't lug engine around town below 2,000 RPM's while driving except maybe on a long interstate drive .
9) Spirited drive on the interstate at least once a month for 15 ~ 20 minutes at 4,000 RPM's

*Not sure of how many of the above actually work to help lower IVD in a GDI engine - but it's what I do ...

 

[MrStamper]

*The approach I take to reduce IVD in my GDI engine :

1) Synthetic oil with low VII's (Valvoline Advance , QSUD , etc.)
2) Use Tier 1 gas
3) Use Fram Ultra oil filter
4) OCI with above mentioned oils of less than 5,000 miles / 4 months .
5) Use CRC Intake Valve Cleaner every 12,000 miles
6) Keep air filter and spark plugs clean and in good condition .
7) Keep PCV clean and operating properly.
8) Keep RPM's up and don't lug engine around town below 2,000 RPM's while driving except maybe on a long interstate drive .
9) Spirited drive on the interstate at least once a month for 15 ~ 20 minutes at 4,000 RPM's

*Not sure of how many of the above actually work to help lower IVD in a GDI engine - but it's what I do ...

I don’t think tier 1 gas makes a difference. I’ve used cheap 87 octane gas to clean tar off my hands. It’s not like chevron with Techron would’ve made a huge difference. I don’t buy into the scam.

 

[OilUzer]

the only way to avoid ivds is going full electric-)

hurry up and buy a MPFI before they stop production. That's why I bought my V8 Tundra earlier than I was planning to because I was afraid Toyota will stop making that engine.

Worst case scenario I may consider a port injected DI but never a full DI.

If I ever have to decide between a full DI or EV ... tough decision, I may get a horse.

 

[ChrisD46]

POE vs. POA ?

 

[SteveG4]

hurry up and buy a MPFI before they stop production. That's why I bought my V8 Tundra earlier than I was planning to because I was afraid Toyota will stop making that engine.

Worst case scenario I may consider a port injected DI but never a full DI.

If I ever have to decide between a full DI or EV ... tough decision, I may get a horse.

Seems that way!

 

[skip029]

Top tier gas, low ash oil, CATCH CAN and Italian tune-up all failed to prevent carbon buildup. Watch Humble Mechanic video:

 

[CarfriendXX]

there already new findings about fullsaps vs midsaps and the deposits on the valves?

 

[SubieRubyRoo]

I’m going to take a different tack here. There are some indicators that it is “whole” oil coming thru the PCV system, but also some that it is oil vapors. If it’s vapors, this is the lighter fractions (thin base oils loaded with VIIs) and higher engine/oil temps promote even more evaporation. I think it’s also been stated that when the VII polymers are sheared or “used up”, they get “sticky”.

So, take your thin, easily evaporated base oil and combine it with sticky VII fragments and run them into the intake at lower RPMs where there is max PCV flow and minimum airflow & velocity thru the ports with no fuel to wash the valve… this sounds like IVD city to me.

To me, the fix is using a higher winter rating (avoiding VII wherever possible) and using a heavier base oil (minimize Noack). Then, in the PCV system you need good baffling & some sort of mesh material to condense & keep oil out of the PCV system as much as possible. If this works, the ashless detergents shouldn’t matter at all because they’re not getting all the way to the intake valve!

 

[CarfriendXX]

Why do all German manufacturers use fullsaps oils as long as possible and change to midsaps only when they have a particulate filter?

 

[High Performance Lubricants]

Because with respect to after treatment, if the oil stays in the pan like it should it no longer matters

 

[SubieRubyRoo]

Because with respect to after treatment, if the oil stays in the pan like it should it no longer matters

What’s HPL’s position on how IVDs happen and what can be done to minimize them, or what should Joe Average look for in oils for cars prone to deposits?

 

[CarfriendXX]

Because with respect to after treatment, if the oil stays in the pan like it should it no longer matters

So I understand correctly that midsaps was really introduced mur because of the exhaust aftertreatment? Cars without particle filters would still be better served with a fullsaps?