Oil colour very dark immediately after oil change

purple_heart77 · Postby **purple_heart77** » December 1st, 2014, 3:10 pm

Vehicle: Skoda Yeti 1.8 TSI (GASOLINE), 95 RON only used
Oil used Pentosin 5W40, colour Amber and Clear
Mileage 25K km

On the last two service at Sterling, as soon as I check the oil it is very dark in colour. The last service (last week Thursday), I pulled the dipstick before I even start the vehicle and the oil is very dark. Brought it to their attention and being told carbon build up. Now mind you they would have driven the vehicle right around the block and back as a "test run". But I really don't know what is going on. The only good thing is the very low mileage Yeti does not burn oil between the 10K km change.

My 6 yr old B6 Passat with same 1.8 TSI (GASOLINE) engine will not see a colour discoloration until about 2 week of stop and go driving. Same oil is used, aftermarket filter installed.

Any reasonable explanation/suggestions on what may be happening?

Additionally Sterling uses a tool that extracts the engine oil from the dipstick holder.

spirited721 · Postby **spirited721** » December 1st, 2014, 3:36 pm

Maybe they not changing the oil...... or its a really bad build up of carbon like they said.

purple_heart77 · Postby **purple_heart77** » December 1st, 2014, 3:46 pm

spirited721 wrote:Maybe they not changing the oil...... or its a really bad build up of carbon like they said.

First impression is to think it is not being changed, but I believe it is being done. Carbon build up, I am not a mechanic, so not sure if both are related, and also if they are, it has such an adverse effect in instantaneously changing my oil. Tough pill to swallow as I compare it to a 100k km VW engine.

racedriverpro · Postby **racedriverpro** » December 5th, 2014, 6:56 pm

purple_heart77 wrote:Vehicle: Skoda Yeti 1.8 TSI (GASOLINE), 95 RON only used
Oil used Pentosin 5W40, colour Amber and Clear
Mileage 25K km

On the last two service at Sterling, as soon as I check the oil it is very dark in colour. The last service (last week Thursday), I pulled the dipstick before I even start the vehicle and the oil is very dark. Brought it to their attention and being told carbon build up. Now mind you they would have driven the vehicle right around the block and back as a "test run". But I really don't know what is going on. The only good thing is the very low mileage Yeti does not burn oil between the 10K km change.

My 6 yr old B6 Passat with same 1.8 TSI (GASOLINE) engine will not see a colour discoloration until about 2 week of stop and go driving. Same oil is used, aftermarket filter installed.

Any reasonable explanation/suggestions on what may be happening?

Additionally Sterling uses a tool that extracts the engine oil from the dipstick holder.

First time I hear about that method to change oil. Daiz a lazy man method tho.
1. They are supposed to drain oil from drain hole to ensure that old oil and muck is removed properly.

2. It is recommended that new oil is used to rinse engine before refilling.

japzor · Postby **japzor** » December 5th, 2014, 7:06 pm

OP change de oil yuh self from now on.

greenlantern12 · Postby **greenlantern12** » December 5th, 2014, 8:45 pm

De man must be change the oil but not the filter and he just outsmart u

purple_heart77 · Postby **purple_heart77** » December 5th, 2014, 11:17 pm

There is a tool that is used for the extraction of oil, generally found at a dealership.

The amount of used oil that has to contaminate new oil to influence a visible colour change has to be a lot, it is the only thought I am leaning to, even if oil filter is not changed, a small amount is in there which cannot make that oil very dark at oil change.

Yes, once warranty is up, I don't have the extraction tool, so normal drain will be done. Hoping to see a difference.

NickJr. · Postby **NickJr.** » December 7th, 2014, 8:45 am

The oil HAS to be removed from the drain plug because the carbon and sediment will stay in the sump and just mix in with the new oil. Who does the oil change on the older car and how?

purple_heart77 · Postby **purple_heart77** » December 7th, 2014, 8:56 am

NickJr. wrote:The oil HAS to be removed from the drain plug because the carbon and sediment will stay in the sump and just mix in with the new oil. Who does the oil change on the older car and how?

In the older car the oil change is done as you described above.

I plan to do next drain the normal way through the drain plug, which I hope to see a difference.

Thanks for your input, I'll report back here in a few months with my finding.

purple_heart77 · Postby **purple_heart77** » May 17th, 2015, 7:35 pm

Decided to go back with one more service at Sterling.
So I got to witness the oil change, it was done as they said, rubber hose into the dipstick holder and sucked out the oil.
I checked the dipstick after the oil was at proper level. It did appear clear, but still not as clear as I would expect, but much better than the previous service.

As I said before, no oil burning, change done every 10K km, 5w40, VW 502 spec. I'll still monitor and see how long before it gets black.

Postby **Team Loco** » May 17th, 2015, 9:17 pm

Ive heard talk about carbon build up on those engines. Maybe try the conventional way next time. See what comes out

purple_heart77 · Postby **purple_heart77** » May 17th, 2015, 10:58 pm

That is the plan.

wagonrunner · Postby **wagonrunner** » May 17th, 2015, 11:19 pm

Team Loco wrote:Ive heard talk about carbon build up on those engines. Maybe try the conventional way next time. See what comes out

I'd let them do the tube thing, and then open the sump before they pour in, to see if / how much old oil there method leaves behind.

Ted_v2 · Postby **Ted_v2** » May 18th, 2015, 6:53 am

Usually about a quart remains.

purple_heart77 · Postby **purple_heart77** » May 18th, 2015, 8:30 am

Ted_v2 wrote:Usually about a quart remains.

Thanks for sharing that.

If 1 quart remains and mixes with new oil, I believe it would account for the "darker than normal" appearance straight after an oil change.

I will do the normal drain from the bottom next oil change.

Big Z · Postby **Big Z** » May 18th, 2015, 8:31 am

I dont like the suction method at all. Leaves behind too many solids in the sump pan for my liking.

Ted_v2 · Postby **Ted_v2** » May 18th, 2015, 1:32 pm

Your both quite right.

Tridenture · Postby **Tridenture** » June 27th, 2015, 12:55 pm

spirited721 wrote:Maybe they not changing the oil...... or its a really bad build up of carbon like they said.

My frist thought too. Something definitely seems fishy about this.

purple_heart77 · Postby **purple_heart77** » June 27th, 2015, 1:26 pm

Tridenture wrote:
spirited721 wrote:Maybe they not changing the oil...... or its a really bad build up of carbon like they said.

My frist thought too. Something definitely seems fishy about this.

That was my first thought, but I personally witnessed the oil change process and it was done as they always told me. But as sited up above, possible a quart of "old oil" is not extracted which sits in the sump pan. This old oil that mixes with the new oil gives the oil an immediate darker than normal colour after the oil change.
Next oil change will be removing the oil drain plug, drain the oil as best as possible and then refill.