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Discussion Starter #1 (Edited)
Hello! So when I took the thottle body off to change the gasket, I noticed that the intake was covered in oil, is this normal? Or something I should be concerned about?
 

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…..if your motor has blow by...yes.

you can use throttle body cleaner and spray inside of manifold clean.....start car and run to operating temp....then change oil to get all that crud out of the motor oil

if you do have blow by, oil will again build up in intake
 

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And adding that there's wide ranging vision of "covered in oil" depending on someone's definitions. Drier, "powderier", more varnish-like as in the case of mine when at 110k is more likely not any more than normal build-up. If more of a wet slime (and especially at your miles) is more indicative of excessive blow-by. So have you had a any operating issues to go with your concern?
 

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And adding that there's wide ranging vision of "covered in oil" depending on someone's definitions. Drier, "powderier", more varnish-like as in the case of mine when at 110k is more likely not any more than normal build-up. If more of a wet slime (and especially at your miles) is more indicative of excessive blow-by. So have you had a any operating issues to go with your concern?
Its more varnish-like.
I havent driven it much, but I havent had any operating issues.
Also how do I check for blow-by?
 

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…..if your motor has blow by...yes.

you can use throttle body cleaner and spray inside of manifold clean.....start car and run to operating temp....then change oil to get all that crud out of the motor oil

if you do have blow by, oil will again build up in intake
Any chance it could be from the pcv valve?
I took the hose off of the thottle body and oil started dripping out of the hose.
 

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Any chance it could be from the pcv valve?
I took the hose off of the thottle body and oil started dripping out of the hose.
Chances are, it's not blow-by. It's crankcase vapor being sucked in via the PCV. Its normal to have some wet looking stuff in there. If you're running a cam with some overlap, even more-so. I put in a catch-can and it appears to have helped somewhat.
 

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Discussion Starter #7
Chances are, it's not blow-by. It's crankcase vapor being sucked in via the PCV. Its normal to have some wet looking stuff in there. If you're running a cam with some overlap, even more-so. I put in a catch-can and it appears to have helped somewhat.
The engine sucking in oil won't hurt anything right?
 

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Op

from your words, "covered in oil" and "dripping oil" from PCV hose to me indicates more than "normal" due to engine use. If this is more like a "black soot or varnish" kind of coating, normal. The dripping oil out pcv hose not, check the pcv is not clogged and works right

Do check/clean PCV. If that hose is dripping oil out of it, clean the inside of hose and use intake cleaner inside of intake as I noted earlier

IDK how many miles you have but if high you can do a compression check and a leak down if you want but I would not be overly concerned about this.
 

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Discussion Starter #9
Op

from your words, "covered in oil" and "dripping oil" from PCV hose to me indicates more than "normal" due to engine use. If this is more like a "black soot or varnish" kind of coating, normal. The dripping oil out pcv hose not, check the pcv is not clogged and works right

Do check/clean PCV. If that hose is dripping oil out of it, clean the inside of hose and use intake cleaner inside of intake as I noted earlier

IDK how many miles you have but if high you can do a compression check and a leak down if you want but I would not be overly concerned about this.
Thanks for all the info!

It has just over 263k. I have done a compression check, and it averaged about 150psi. I bought this car about 6 months ago so I dont know if the engine has been rebuilt/replaced.

Is the pvc valve somthing that should be replaced?
 

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My PCV is normally wet on the underside (and yes, you should change it out every year or so. Its cheap insurance.) There's also usually a wetness inside the manifold, even with my catch can. My compression tests and leakdown numbers are top notch. For MY car, the stuff in the intake is normal. Any car is going to have some crap in there. As I stated before, I'd bet diamonds to dollars it isn't oil but is instead a mixture of condensation and oil vapor, which is to be expected. The temperature differential between the intake manifold and the intake air will create some moisture all by itself. If the stuff is more watery than oil, then its vapor and condensation. If its oil, then you need to sort that out.

Now, if you can hold the intake up and it drips out, then you've got problems. If it's just a general dampness in there, I'd not lose any sleep over it.
 

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Thanks for all the info!

It has just over 263k. I have done a compression check, and it averaged about 150psi. I bought this car about 6 months ago so I dont know if the engine has been rebuilt/replaced.

Is the pvc valve somthing that should be replaced?
PCVs are very cheap, so yes, replace it and all the rubber parts should be checked for vacuum leaks, proper sitting etc. If the car is rarely driven, there may be excessive moisture in oil as well. Take a long trip, change oil.
 
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