Oil in the airbox - might be an easier fix than you think FAQ
#1
01-23-2012, 02:19 PM
Oil in the airbox - might be an easier fix than you think FAQ
Hello guys;
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
Last edited by The Coupe; 01-24-2012 at 02:49 PM.
#2
01-23-2012, 02:57 PM
#7
01-23-2012, 04:05 PM
Join Date: Oct 2007
Location: PHX some of the time
Posts: 116,690
Received 6,242 Likes
on
5,443 Posts
Trending Topics
#8
01-23-2012, 05:11 PM
Veteran Member
Join Date: Nov 2006
Location: Glasgow, Scotland UK
Posts: 47,304
Received 9,005 Likes
on
4,113 Posts
#10
01-23-2012, 05:42 PM
That's really strange...I uploaded the photos to an album right here on the forum specifically to avoid that problem. And some people can see them just fine.
Dearest Mods, could one of you please look into the problem that Skid and Malbec are having?
As the icon dudes say,
Dearest Mods, could one of you please look into the problem that Skid and Malbec are having?
As the icon dudes say,
#11
01-23-2012, 05:46 PM
Veteran Member
Join Date: Nov 2006
Location: Glasgow, Scotland UK
Posts: 47,304
Received 9,005 Likes
on
4,113 Posts
#12
01-23-2012, 05:51 PM
Veteran Member
Join Date: Nov 2006
Location: Glasgow, Scotland UK
Posts: 47,304
Received 9,005 Likes
on
4,113 Posts
Now??
Hello guys;
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
#13
01-23-2012, 06:16 PM
Join Date: Sep 2008
Location: Damon /Houston, Texas
Posts: 7,254
Received 2,183 Likes
on
1,355 Posts
#18
01-24-2012, 05:16 PM
Join Date: Sep 2008
Location: Damon /Houston, Texas
Posts: 7,254
Received 2,183 Likes
on
1,355 Posts
#19
01-26-2012, 02:17 AM
Senior Member
Hello guys;
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
I bought my coupe back in June 2011, and almost immediately started worrying about oil that was showing up in my air filter. After some reading, some thought and a couple of new parts, I've solved the issue...and the source of the problem was NOT typical. So I'm posting this up for the next guys who might worry over oil in their airbox.
My pre-purchase inspection report for the car listed "oil in the airfilter and airbox...likely indicates excessive blow-by." Egads. But I bought the car anyway...the price was too good to pass up (maybe this is why!).
As I put my first 2,000 miles or so on the car, I watched the airbox carefully. Sure enough, oil was typically found in the air intake tube, and on the filter. The oil was coming into the intake from the Full-Load Breather Tube, which connects the intake to the right-hand cam cover. The MAFs was getting dirty, and the oil had also fouled the throttle body to the point that I experienced a stall at speed, on the highway. Egads again.
Here's a snap of a new air filter, after only 400 miles of driving:
This much oil in the intake usually means one of two things:
1. THE EXPENSIVE PROBLEM: Excessive blow-by. So much compression leaks past the pistons that positive pressure in the crankcase literally blows oil mist out of any available hole. Could be nikasil, or just a worn out engine. No real fixes here but a rebuild or replacement engine.
2. THE CHEAP or FREE PROBLEM: Blocked part-load breather orifice. This opening on the LEFT hand cam cover connects via a tube to the throttle body and EGR. It's a small opening that can become blocked with carbon deposits, forcing higher than normal crankcase pressure that can result in oil blowing out the RH cam cover and into the intake. Clearing out the blocked part-load breather orifice can be done easily with a 3/32" drill bit. Unfortunately for me, mine was completely clear...which meant my problem was likely excessive blow-by. Right? Nope.
As it turns out, my RH cam cover was simply missing its oil separator. Beneath the hole for the Full-Load Breather tube- the tube that connects to the air intake- there is supposed to be two small wads of metal mesh, held in place by a metal plate. This simple design helps to prevent liquid oil and oil mist from being blown up into the breather tube at higher engine speeds.
Once I knew to look for it, I could immediately see that my oil separator was simply missing. When I disconnected my Full-Load Breather Tube from the RH cam cover, and looked down into the hole in the cam cover, there was no oil separator blocking my view of the camshaft. Here's a snap of what that looked like:
If you look into the breather hole in your RH cam cover and see a camshaft, as in the photo above, your oil separator is not in place. And you are likely suffering with oil in your airbox, along with a dirty throttle body and MAFS.
The oil separator is snapped into place when the cam cover is manufactured. At some point during my car's maintenance with a previous owner, it was removed. God knows why...I sure don't. Here's how the oil separator is constructed...
Now I was starting to feel better...maybe my problem wasn't excessive blow-by. Maybe I just needed a new cam cover, with the oil separator in place. Here's a photo of the old and new cam covers, side by side.
I installed the new RH cam cover, with the oil separator in place. Now, obviously, when I look down into the hole for the Full-Load Breather Tube, I can't see a camshaft anymore. Just the metal of the oil separator. This is what you want to see when you look into your own...
I am happy to report that I've now driven 3,000 miles with the new cam cover and oil separator in place. I have had NO OIL IN MY AIRBOX. The filter, intake tube, MAFS and throttle body are all clean. Have a look:
So, the take-away is this: if you've got oil in your airbox, yes - you might have excessive blow-by, or you might have a blocked part-load breather. But before you do anything else, do a quick check to make sure your oil separator is in place. Just pull off the Full-Load Breather Tube where it connects to your RH cam cover...but do it carefully, because the plastic is probably brittle.
Thanks for all the help you guys provide. My hope is that some guy worrying about oil in his intake- and using the search function in this forum- will benefit from this particular journey of mine.
The following users liked this post:
Fn2damax (03-05-2012)
