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brown coolant, help? 07 WRX

2793 Views 4 Replies 3 Participants Last post by  BLKSTI05
I have an 07 wrx with 98k miles, mods:
16g turbo
external wastegate
sti inter cooler
750cc injectors
300 fuel pump
and an sti trans
i think that is all.

I noticed my coolant is chocolate brown. Before I diagnose it as my worst nightmare, a blown head gasket, what else could cause this to happen?

I only ask because there is no coolant in my oil, both oil and coolant levels remain constant, the motor does not overheat and no smoke. The only symptoms are the brown coolant and my turbo for some reason sounds a lot louder, like the wooshing and whistling comes about at way lower RPMS than the usual.
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Re: brown coolant, help?

Typically when I see the coolant that looks brown its because has oil or trans fluid mixed in. Other times if it has dex cool the gm coolant it will also turn brown if its not changed at the proper time. I'd suggest doing a coolant flush and see if the brown coolant returns.
Re: brown coolant, help?

Agreed. Your first move should be a flush. And examine the old coolant, oil and water will separate.
Re: brown coolant, help?

Okay so I took a closer look its still very watery but after that I realized its rust. My coolant system has rust which isn't good and I'm hoping it could just be the radiator.
Re: brown coolant, help?

Your right, rust is bad. Flush the system and recheck. Also make sure you get the heater core clean when you do the flush.
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