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YOUR RESEARCHFuel dilution ?
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Check also
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Performed · outcome unconfirmed · Original poster
Searched forums and very few hits unless I am using bad search terms.
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Suggestion
^^ Your $ would be better spent on checking the injectors...
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03 C4S with 58k
I just received first oil analysis. I am using Motul X-Cess 5W-40. All looks really good except for warning on fuel dilution. No hard codes or pending codes.
Searched forums and very few hits unless I am using bad search terms.
Any experience ?
David
How many miles on the oil? Depending on the amount of fuel in the oil (per miles) you may have 1 or more failing fuel injectors. According to FSI/LE Engineering, this is a major cause for bore scoring! You should have them checked and if it turns out they're bad have them re-furbished or replaced (could just be seals/o-rings...). Good luck
First oil analysis since I owned the vehicle. Only 1000 miles on this oil. Have been doing quite a few short runs recently. Will pay to have sample double checked also.
I agree. But given I am in this Industry and I am aware of the typical repeatability of this test I would rather have 2 data points before I get too alarmed. Cost will be around $8. I will however check the injectors if I have any concerns. The reason I am somewhat questioning the injectors as the engine only has 19000 miles on it. This was a crate engine installed by Porsche.
I do appreciate your quick responses. Thanks !
David
Short runs means the crankcase doesn't stay warm enough for the fuel to be evaporated out. Do check the injectors, but also take some longer drives so the engine is fully warmed for a while.
Make sure you take a long drive with the oil hot b4 the next change and sample. Thats what should be done b4 every oil service, to get best money's worth out of the oil sevice. Oil needs to be hot and dry when draining and changing filter to drain best and get the cleanest oil on refill.
If you take many short trips, where the engine does not get a chance to get up to temperature for 1/2 hour or more, fuel and water vapor that would “Burn Off” will build up in the oil. That is one of the reasons the manual considers short trips to be “Severe Duty” and calls for shorter intervals between oil changes.
Wait until you remove the oil fill cap after a series of short runs especially in the colder weather. There can be 1/2 cup of yellow schmutz under the cap. This is a combination of oil and water vapor that has transmogrified into a stinky yellow jello that condenses on the “cold” oil fill tube and cap.
With that said it is always prudent to double check tests when one turns up an anomaly. Especially with one of these expensive, finicky engines. You wouldn’t want to ignore a leaky injector.
I read somewhere (don't recall exactly) that you need at least a 40-60 minute drive at speed to burn off all the water and fuel.
I would do that right before the next oil change, then analyze again. If still high, then start looking for mechanical causes.
If it were me, I'd drive it for an hour, three days in a row prior to the oil change to make sure.
Plus, you get to enjoy your car more!
Ok
My test lab re measured for free. Average of two numbers was 1.8% +\- 0.1 %
I am strongly leaning toward earlier posters comments. Sample was pulled after car had been shuttled around a mile here, 2 miles there. Oil was cold.
It does smell very rich on cold starts so I am sure the cold start enrichment is in full effect.
I will wait for the next sample before I pull the injectors out.
Thanks for good input.
David
