Effect of 2-stroke in DI?

[JHZR2]

Noticed this for the first time today, about 100mi into this first tank that I used tcw-3 vice redline SI-1.

I only added about 1.5oz in 10-12 gal (don't recall exactly off the top of my head).

Maybe not related but I never noticed it before and it is pretty oily...

 

[sunfire]

Which brand of TC-W3 did you use? And I assume you mean maintenance dose of SI-1.

 

[JHZR2]

Yes to the maintenance dose of Si-1, and I used amsoil Saber 100:1 ATO.

I've used the saber ATO in my other BMW and Saab with no indicationof anything like this...

 

[mikered30]

Which engine?

 

[JHZR2]

2011 BMW 135i, N55 twin-scroll turbo, DI.

 

[sunfire]

Clean one of the tail pipes see if it persists with Saber. Leave the other as is for reference. After you run the tank down go back to SI-1. Clean the tail pipe again and check.

 

[fdcg27]

Why would the DI system make any difference?
The oil is burned with the fuel, just as it would be with port injection.
Also, what purpose would the addition of oil serve in a DI engine?
I guess you'd get some lubrication of the fuel pump and injectors?
You obviously wouldn't gain anything with the valves.

 

[hate2work]

Hey, another reason to use 2 cycle top oil, it rust-proofs your tailpipe

The most important question is... Was this there before you put the oil in the gas? I'd hate to think that a new car was pushing this much (what appears to be) carbon out the exhaust system.

 

[demarpaint]

I noticed my tail pipe was cleaner with MMO vs TCW3, but nothing like what's in the picture. OTOH oil use is down a little in my Aerostar using TCW3 instead of MMO in the gas. I will continue to experiment switching it from MMO to TCW3 so I can be 100% sure.

 

[bullwinkle]

I understand the benefit of 2-stroke in a diesel-but why in a modern fuel-injected gasoline engine-aren't you taking chances with the catalytic converter & O2 sensors?

 

[sunfire]

Originally Posted By: bullwinkle
I understand the benefit of 2-stroke in a diesel-but why in a modern fuel-injected gasoline engine-aren't you taking chances with the catalytic converter & O2 sensors?


All engines burn motor oil, some more some less. So engines that burn motor oil have bad cats and O2 sensors?

 

[JHZR2]

Tcw3 is ashless and has been discussed at length on here.

 

[sunfire]

If you go through the UOA section there are people that go through a quart of motor oil every OCI. I don't see them replacing their cats and O2 sensors frequently.

TC-W3 is ashless so it should be even less harmful than motor oil.

 

[demarpaint]

Originally Posted By: bullwinkle
I understand the benefit of 2-stroke in a diesel-but why in a modern fuel-injected gasoline engine-aren't you taking chances with the catalytic converter & O2 sensors?


I'm using about 1 qt of oil ~ every 3K miles, I also add either MMO or TCW3 to the gas. The vehicle now has 190,000+ miles with the original CC and 02 sensor. I don't see any problems.

 

[Audi Junkie]

I don't see many cars on the road w/o soot on the pipes.

 

[Loobed]

Originally Posted By: JHZR2

I only added about 1.5oz in 10-12 gal (don't recall exactly off the top of my head).

... I used amsoil Saber 100:1 ATO.

I've used the saber ATO in my other BMW and Saab with no indicationof anything like this...




1.5oz of 100:1 TC-W3 oil is like 3.0oz of regular TC-W3 oil.

Is the soot on the tail pipe oily or is it just water? Water is normal after the first few minutes the engine runs after being cold.

 

[CourierDriver]

go to www.ls1.com add one oz of 2 cycle oil with tcw3 to 5 gallons of gas,,very weak, no more, no less.

 

[JHZR2]

Originally Posted By: Loobed



1.5oz of 100:1 TC-W3 oil is like 3.0oz of regular TC-W3 oil.

Is the soot on the tail pipe oily or is it just water? Water is normal after the first few minutes the engine runs after being cold.







That's a good point... I kind of assumed that the 100:1 was more of a sales gimmick than anything else, like "our oil is better at protecting so you can use less", vice more concentrated...

This is oily. I know what you mean about the moisture, and this was oily on my finger, thats why I touched it, to see...

I had not seen it before, and the tailpipes are othrwise not sooty, per my run the finger over them test.

 

[sunfire]

Saber is more potent than hp injector and other TC-W3. Even 3 oz of regular TC-W3 shouldn't cause oil out of the tail pipe.

 

[BobFout]

Originally Posted By: Audi Junkie
I don't see many cars on the road w/o soot on the pipes.


It's funny to see sparkers that soot. DI gas engines even clatter at idle.