[Biturbos4] Turbo reliability

costco keman at interwolf.net
Wed Aug 31 11:57:41 EDT 2005

Pinch the two hoses (one at a time with either strong fingers or a pair of
needlenose pliars) leading to your bypass valves under the center engine
cover (the one that says biturbo v6). Stock, one is fabric covered, one is
rubber, the valves face away from each other. The hoses are roughly 3/8"
in diameter and fairly short. The bypass valves themselves are shiny
plastic P looking things. You'll see them right away when you remove the
engine cover.

If the noise you describe goes away when you pinch one of those lines
shut, that particular bypass valve is toast and needs to be replaced.
Better to replace them by the pair. They fail often, even the improved

- Keman

On Tue, 30 Aug 2005, Philip Pace wrote:

> <breathes giant sigh of relief>
> That's the setup I got, but now it's making an obnoxious noise at idle. If you make
> a dial tone noise, that's about what it sounds like. Thoughts? It goes away on
> boost, and is most noticeable after the car was running, turned off for a bit, and
> then started again. If the oil temp gauge settle back to 150º, it doesn't make the
> noise on startup at that point.

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