I'm concerned. yellow gunk under oil filler cap...

I changed my oil and under the oil filler cap there was yellow gunk. There was a trai of yellow fluid trailing dorn from the filler cap into the engine. There was a small deposit of yellow gunk up in the top/inside of the filler cap. What is this stuff?

I've been using synthetic 5w20 for the past few oil changes after buying my 06 trd used. previous owner used conventional.

I changed my spark plugs approximately 1500 miles back. Other than that I don't know what else to add.

I'm concerned that when changing my spark plugs (for the first time) that I frigged something up because my fuel economy has been crap lately too. (might just be because I'm running 265/75/16 studded mudders)

 

Some moisture in the oil.

 

Sounds like blinker fluid residue.

 

Like yellow yellow or yellowish? lemonade, or fresh oil
thick or watery?

 

Sometimes a lot of short trips where the engine oil doesn't get up to full temp will also cause that.

 

Drive more so the water evaporates, its just condensation in the fill neck. Should be fine.

 

Yep...nothing to worry about

 

Its lube from the cap. My truck is only 3 months old and I noticed it the first oil change that I did. It wont hurt anything.

 

mine does that too.

 

I was freaked out the first time I saw what looked like mayonnaise on the oil filler cap and PCV valve on my old car. Short city trips will do that. Go drive a good long highway drive to get the oil up to full operating temp for a while. It will drive the water out of the oil.

 

Yep, freaked me out the first time I saw it too. Looks like mud or something.

 

really bad VD, you should go to the Dr.

 

Make sure your not using coolant. My last vehicle had that ( not a toyota ) Turned out to be a cracked head.

 

it's an infection,its called engine pus

 

I just changed my oil last night and noticed the same thing. It's condensation from heating/cooling cycles. I've never had a vehicle that I've noticed this on before. I do virtually all highway driving, my commute to work is 25 miles each way on freeway, so I know the oil is getting up to temp. I keep a close eye on coolant and have not used any in 15k miles.

Oh well, I'm sure it's not really a problem.

 

Hey fellows. I've been a member for a while now but this is my first post. I logged-on this morning to read about this very subject. I have just rolled over 115K on my 05 V6 4x4. I have been the ONLY person that has ever done ANY PM on my truck. At 3K I drianed the factory oil and began using RP 5-30. This truck has only seen RP 5-30. I have always done my oil changes at 7,500-10,000 miles. For those of you that know & use RP products you will understand how I rest assured knowing my truck is well taken care of. This past w/end I changed my oil and it was at 11K cince my last change. Now, this is by far the longest that i have gone on an oil change. When I changed it this time I noticed, for the first time ever, that I had a "yellowish gunk" under my oil cap as well as in the filler tube. I removed the tube, took a sample,washed it as well as the cap and re-installed them. After draining the oil I took my flexable fiberoptic light and looked around inside the timming chain as well as the walls of the case. NOTHING! This was not good enough for me so I then proceeded to get back under the truck and removed the oil pan to inspect. NOTHING! I completed the oil change and documented the issue in my ongoing excell document. I know, I know. I am that guy!
In my profession I have the luxury of being able to use some of the finest molecular testing available. After returning to work yesterday and examining the sample I can report, w/ 100% certainty this condition was caused by moisture in the oil. The break-down (for you geeks out there) is as follows: 97.3% synthetics, 2.1% H2O, .6% (w-code ,dirrivative of the refining process) or "contaminants.Now as we all know hydrogen can ONLY be introduced to any invironment in two ways. First, it was intrduced on purpose (adding water) and we know that did not take place. Second, atmospheric (the cooling and heating of any liquid).
Knowing that I have not seen this to date I am in the process of reserching this issue. Taking into consideration that I often go as long as 9K-10K on an oil change (but ONLY when the miles in that time-frame are highway miles) I have never gone as long as I did on this past change, 11K. I have to conclude that in the time/miles from 9K to 11K the H2O content rose. This is the question at hand. I will find out why as I am that guy!
I'm sorry, did you just want to know the time or did you want to know how to build the watch?

BTW, this is a great location to find answers to many questions you may have to do with Toyaot Tacomas. Keep it up.

Curt
2001 Taco V6 4x4 (272K miles)
2005 Taco V6 4x4 (116K miles)
2008 4Runner V6 4x4 (23K miles) wife's
2010 Land Cruise 4x4 (4K miles) too many extras to mention...

 

No need. The only reason the mayonnaise-like deposits exist is because of cold-weather condensation inside the cold parts of the engine. The oil fill tube is a big, cool insulator.

The water is trapped in the mayo and does no damage. When the weather warms up, the water will be driven out and removed via PCV.

 

Sounds like pollen..................

 

Unless a chunk of it it falls off and blocks an oil galley and burns up something in the engine .