I've had a bottle of Seafoam sitting around for a while and wanted to try it on my Malibu to see if it will help with some oil consumption and rough idle. It's not a lot but it's almost a quart down after 5000 miles, but it has never used any oil before. I'm planning on changing my oil very soon as well, so I figured I might put some in the oil as well before changing it. I've used Seafoam a couple times in other other cars. It helped in one case but not the other so it's worth a shot.
Anyway, I was planning on using the brake booster line like is usually directed, but on my car it seems like the brake booster vacuum line goes directly into one of the intake runners which isn't very helpful. There is another line that goes from the valve cover directly to a part right before the throttle body. I was wondering if this will work well to suck the Seafoam in to the intake.
This particular line is part of a non serviceable PCV valve (built in to the valve cover) and recently I have noticed that there is oil seeping around the end of the hose so I know there is probably some build up of oil in the intake. I just want to make sure this will work okay for what I'm planning to do. Here are a couple photos showing what I am referring to: https://imgur.com/a/aq7hs
Seafoam Question
- Thread starter RoGuE
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I love how clean your engine looks,I try to keep our 05 6cyl Malibu the same way,i see you have me beat!
I have the same engine, oil consumption has increased from 1qt/8,000m at 100,000 miles to 1qt/2,800m at 196,000 miles. Seems to be the nature of the beast. Low tension rings maybe?
The line from the valve cover to intake is the line to use for seafoam. At idle, the engine should want to draw air into the valve cover if the PCV system is operating properly. You can feel this with your finger if you block the opening to the valve cover but don't do this for too long as you will create a vacuum in the crankcase and draw ambient air in around the engine seals. I don't think pouring seafoam into the valve cover port will really clean the PCV system as the seafoam will just mix with the oil in the top of the head.
Adding seafoam to the intake, via this valve cover line, would be the best way to "treat" the engine but this will set a trouble code as air/seafoam is entering the engine without passing the MAF sensor.
An overly dirty air filter can cause a higher than usual vacuum in the intake tube which will draw excess crankcase vapours into the engine from the valve cover area. You might want to check that first.
Put it in a spray bottle and spray it against the throttle plate with the RPM at 1500-2000. Clean the Throttle Body at the same time.
Your overly long oil changes is why your engines use oil. My FIL just parked a Malibu with 435,000 kms on it. Doesn’t use any oil. Oil changed every 3000 miles/5000 kms since new.
My Santa Fe didn't use any oil when it died at 535,000km (300K miles) on 10,000km (6,000 mile) oil changes. I would have pushed the OCI further but the engine was really hard on oil so I couldn't.
Or, we could stay on topic. The use of Seafoam.
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Originally Posted By: WobblyElvis
Or, we could stay on topic. The use of Seafoam.
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I put seafoam in the crankcase and gas tank at the same time. Seafoam is also a upper lube too. It lubes the valve guides, valve seats, frees and reseats stuck piston rings. By the time I need fuel again the idle has smoothed out, the idle is a higher rpm. The engine seems to be happy, happy, happy. My generator had a gummed up carb. I added seafoam tothe gas tank and forgot about it. Months later we fired it up and the carb was cleaned.
Originally Posted By: Bigbill
I put seafoam in the crankcase and gas tank at the same time. Seafoam is also a upper lube too. It lubes the valve guides, valve seats, frees and reseats stuck piston rings. By the time I need fuel again the idle has smoothed out, the idle is a higher rpm. The engine seems to be happy, happy, happy. My generator had a gummed up carb. I added seafoam tothe gas tank and forgot about it. Months later we fired it up and the carb was cleaned.
Originally Posted By: kschachn
Originally Posted By: Bigbill
I put seafoam in the crankcase and gas tank at the same time. Seafoam is also a upper lube too. It lubes the valve guides, valve seats, frees and reseats stuck piston rings. By the time I need fuel again the idle has smoothed out, the idle is a higher rpm. The engine seems to be happy, happy, happy. My generator had a gummed up carb. I added seafoam tothe gas tank and forgot about it. Months later we fired it up and the carb was cleaned.
Originally Posted By: oilmutt
I love how clean your engine looks,I try to keep our 05 6cyl Malibu the same way,i see you have me beat!
Originally Posted By: WobblyElvis
I have the same engine, oil consumption has increased from 1qt/8,000m at 100,000 miles to 1qt/2,800m at 196,000 miles. Seems to be the nature of the beast. Low tension rings maybe?
The line from the valve cover to intake is the line to use for seafoam. At idle, the engine should want to draw air into the valve cover if the PCV system is operating properly. You can feel this with your finger if you block the opening to the valve cover but don't do this for too long as you will create a vacuum in the crankcase and draw ambient air in around the engine seals. I don't think pouring seafoam into the valve cover port will really clean the PCV system as the seafoam will just mix with the oil in the top of the head.
Adding seafoam to the intake, via this valve cover line, would be the best way to "treat" the engine but this will set a trouble code as air/seafoam is entering the engine without passing the MAF sensor.
An overly dirty air filter can cause a higher than usual vacuum in the intake tube which will draw excess crankcase vapours into the engine from the valve cover area. You might want to check that first.
I wouldn't expect the valve cover side to be drawing in air. Okay, I'll add it through this line into the intake. If it sets a code I have a scantool I can use to clear it.
The air filter shouldn't be dirty. I replaced it maybe a year ago and I don't really drive in dusty environments, but I'll give it a check.
Originally Posted By: StevieC
Put it in a spray bottle and spray it against the throttle plate with the RPM at 1500-2000. Clean the Throttle Body at the same time.
Originally Posted By: FastLane
Your overly long oil changes is why your engines use oil. My FIL just parked a Malibu with 435,000 kms on it. Doesn’t use any oil. Oil changed every 3000 miles/5000 kms since new.
Yeah that sounds fine...
So I went ahead and used the Seafoam today. I put about 5.5 oz in the oil, and then used about another 1/3 through the intake. I tried using it through the line I had discussed earlier, and for whatever reason it would not suck up anything through that line, even when the engine was revved up. I don't know if it is blocked or what but it wouldn't work. I ended up pulling the air intake off the TB itself and dribbling it in. It faces up at about a 45 degree angle so it was possible, if not a little messy.
After it was all in I had someone cut the ignition and it actually continued to sputter for about 2 seconds. Waited 10 minutes and it started right up. The rough idle is still present but the throttle response is slightly improved, though I suspect this is largely from the TB itself getting cleaned.
I'm just not sure why there wasn't any suction from the line. The valve cover side of the line felt like it was blowing out air. Also worth noting the engine seemed to run fine with it removed, as if there wasn't even a vacuum leak. Anyway, here's a bonus Seafoam smoke video, I apologize for the vertical orientation: https://www.youtube.com/watch?v=-POtXOq_o_U
The line from the valve cover to the black plastic intake tube is not controlled by a valve. It is simply a vent for the crank case gases. Where the intake manifold bolts to the head there is a small orifice that allows crank case gasses to be sucked into the manifold. At idle this vacuum is high and filtered air is drawn into the valve cover from the black plastic intake tube. At idle a vacuum should be felt at the valve cover port. If not, the passage to the intake manifold is obstructed, the engine is not sealed or there is considerable blow-by past the rings.
Under high load, blow-by gasses may exceed the normal flow of the passage to the intake manifold and excess gases are normally vented out the valve cover port and into the intake tube upstream of the throttle body. Should there be excessive wear on the engine, large amounts of blow-by gasses will leave an oily residue on the throttle body plate. Normally there is no vacuum in the black plastic intake tube as air can freely enter it via the air filter. The only way to get seafoam in there would be to spray it. [I should have mentioned this earlier].
Removing the line from the valve cover to the intake tube allows unfiltered air to enter the engine so it should not be left off for long. Air blowing out of the valve cover port at idle is a sign of trouble.
Thinking back on it, it's hard for me to say for certain whether air was blowing out or if there was a vacuum on the valve cover side. But you mention "At idle this vacuum is high" and this was certainly not the case. The engine RPMs didn't change one bit when I removed this line. I don't think it would be "considerable" blow-by... a little less than one quart of oil used in 5500 miles. I checked the little hose itself and it was clear. So what's left, an obstruction? How do I check/repair that?
At idle, air should be pulled into the valve cover. Pull this hose off and put your finger over the valve cover port. You should feel a vacuum within a few seconds. Don't leave you finger there to long or the vacuum will reach the point where it starts pulling air in around the seals on the crankshaft. If there is no vacuum at all, then there is some obstruction in the pcv system. This is not very likely or you would find a lot of oil on the throttle body plate.
If the engine suffers from blow-by past the piston/rings, the oil will turn darker faster than usual and you might find black/carbon/soot in the pleats of the oil filter. A quart of oil every 5,500 miles is not really excessive although a little disconcerting at that mileage.
For a 2007 model it is unlikely that the pcv passage from engine to intake manifold is obstructed but it is possible.
The orifice where crank case gases enter the intake manifold can be seen in this link.
http://www.redlineforums.com/forums/atta...ion-l61_pcv.jpg
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