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So do you have to do an oil change after the seafoam? Ive heard both ways and dont want to do it unless Im completely sure
You only do an immediate oil change (i.e. within 100 miles) if you add Seafoam to the crankcase. This is a way to clean the engine internals when you are planning an oil change.
When you run Seafoam through the Secondary air valve you don't need to change the oil, you will see the Seafoam and carbon deposits burn off in the white smoke.
 

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You only do an immediate oil change (i.e. within 100 miles) if you add Seafoam to the crankcase. This is a way to clean the engine internals when you are planning an oil change.
When you run Seafoam through the Secondary air valve you don't need to change the oil, you will see the Seafoam and carbon deposits burn off in the white smoke.
Make Sense..
 

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Please check your hose! When pouring in the seafoam I saw a leak. It was about the size of a pin head. I replaced the hose. When I went to pull it off it was completly drie rotted from the inside. I have not even seen a hose this bad in the restoration jobs I have done and some of those hoses were still OEM from the 60's.
 

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Seafoam not flowing down

The air pump's working since I can feel the airflow after I disconnected the hose. But the seafoam stayed in the hose after even 3 5-sec cold start. I left the seafoam in the hose, drove around, parked around overnight for it to soak in, but the seafoam's still mostly there the next day!

Does this mean I have bad valve or vac line? How do I make sure the seafoam gets in to rid the likely blockage before I can diagnose other issues
 

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The air pump's working since I can feel the airflow after I disconnected the hose. But the seafoam stayed in the hose after even 3 5-sec cold start. I left the seafoam in the hose, drove around, parked around overnight for it to soak in, but the seafoam's still mostly there the next day!

Does this mean I have bad valve or vac line? How do I make sure the seafoam gets in to rid the likely blockage before I can diagnose other issues
You probably have either:
A bad vacuum hose
a plugged valve
or both.

I just replaced the entire vacuum line from the vacuum valve on the rear of the intake manifold to the Secondary Air Valve on the front of the cylinder head.

The best thing to do is to remove the cabin air filter housing, the coil cover, and the fuel injector cover. That way you can see the entire vacuum hose/line assembly. My vacuum hose was broken, as was my vacuum hard line. You can get the part numbers from the Real OEM site, and the parts run about 25 bucks.
 

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let me get the straight.
1- unplug the hose
2- pour sea foam in hose
3- while hose is unplugged run the car for 5 sec OR do i plug the hose back on?
4- repeat this 3 times at least.
5- plug everything back together.
6- expect white smoke.

let me know thanks guys!
 

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Did this today and poured the seafoam...turned car on for a couple of seconds then went back to check...seafoam still in there...did it a couple more times to see if it will go down...nothing coming out the secondary air pump...is there suppose to be air coming out? Or is it possible that I let the car warm up too much for it to work?

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Did this today and poured the seafoam...turned car on for a couple of seconds then went back to check...seafoam still in there...did it a couple more times to see if it will go down...nothing coming out the secondary air pump...is there suppose to be air coming out? Or is it possible that I let the car warm up too much for it to work?

Sent from my SPH-D700 using Bimmer App
I did it with my car cold. Sat overnight and seafoamed first thing in the AM b4 the sun
 

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My SES light is on as well and having some rought idling once in a while with the cold start. Went to a mechanic shop and got the codes read and they suggested cleaning my fuel system. They recommended something other than seafoam due to it being harsher, possibly more corrosive. I wasnt too sure what to think of his advice so was wondering what you guys think. I did however buy some gumout and put it in my fuel tank. Before I try this I just want a good solid answer to whether seafoam could harm my car.
 

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As far as I know...seafoam won't harm anything in your car

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I just did this the other day and it seemed to work. My car wasn't having any big problems, I just had some SeaFoam and thought I'd give it a try. The car has 82k on the clock. There was one complication, the hose was rotted near the bottom and I had to replace it before I could do the procedure. But everything worked as expected with the new hose, with one exception.

When I fired up the car to burn off the SeaFoam, all the white smoke was coming out the driver side exhaust pipe, but not the other. Does this mean the ports in the exhaust chamber are plugged on one bank? I drove the car for over 30 miles after the treatment and it ran like a champ. But the following day the car threw a P0174 code. Still runs great though.

So, could the SeaFoam treatment affect the O2 sensor? Could all the SeaFoam have gone into one bank only? Which bank exhausts through the drivers side tailpipe?

I'm hoping some of the SeaFoam may have worked it's way into the carbon buildup on the other bank and another treatment will clear it out. Also, I haven't checked all my hoses for vacuum leaks, a possible cause of the P0174, but if it was a vacuum problem wouldn't I throw a P0171 also?

Thanks

DAC
 

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My car has been throwing P1421 the past week or so. I cleared it last week and put about 500 miles on the car and it didn't come back on until today. I just bought my can of seafoam and will be doing this treatment later on tonight when the car is cold. I already replaced my hose because it had a large hole in it, so we'll see if this does anything.
 
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