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Loud secondary air pump

29501 Views 65 Replies 12 Participants Last post by  vaboxr
My 97-528 SAP is kind of loud compares to my 02-530.
It's a fast loud thumping sound.
I think the air passage may have been clogged, but then again this maybe normal for 528.
How's every 528 SAP sound in the morning? Thanks for the feed back.
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Good job on isolating the problem:thumbup:

Before you do that seafoam madness, try removing the valve, and let it soak in WD-40 overnight. If the valve is partially sticking mechanically, this soaking will free things up.
If the valve isn't opening up due to other issues, like a diaphragm malfunction, then most likely a replacement is what's needed. :dunno:
Glad to hear !

So what exactly is this Seafoam supposed to be cleaning when it's poured down that large hose?

Looks to me like if I poured Seafoam down this hose on my '98, it'd go down directly to the pump, would it not?

I think the part needing a Seafoam cleansen is the valve itself, isn't it?
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