Yeah, it's the Solstice again.

I just replaced a v-band clamp between my turbo and the cat. The engine runs a lot smoother now - go figure - but it's running quite a bit warmer.

Before I recently replaced the VVT actuators, I would see 205-211 (Fahrenheit, which should be obvious as I did not spontaneously combust) when doing 80MPH for any length of time. After replacing the actuators, this dropped so it never really got over 200, more like 185-190 around town.

Today, I replaced a wonky V-band clamp connecting the turbo to the cat. Car runs a LOT smoother, though it feels a bit sluggish. That's not terrible, just slightly annoying and probably due to the fact that I'm no longer running a semi-open exhaust (big leak).

On the way to dinner, I noticed temps once again hitting 205-207.

So, my question is: WTF?

  • Is 207 not in the operating range of your vehicle? most engine operate from 190-220
    – method
    Sep 23, 2016 at 23:48
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    @method with a leak, less unburned fuel makes it to the O2 sensor, so it reads leaner than it really is. Computer compensates by adding fuel... Thus, rich. (Some of the unburned fuel goes out the leak, which in this case is before both O2 sensors)
    – 3Dave
    Sep 24, 2016 at 2:35
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    @Pᴀᴜʟsᴛᴇʀ2 that makes sense in some cases, but my AFR cruising at 80ish is roughly the same as it was before (14.5 +- 0.6ish). That's when the temps really start to jump. I probably effed something else up. I'm getting a sticker that says" I Am Tolstoy's Other Car"
    – 3Dave
    Sep 24, 2016 at 2:38
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    @method also, your exhaust is always pressurized when the engine is turning. No real opportunity to suck in air through an exhaust leak. Intake is a different story.
    – 3Dave
    Sep 24, 2016 at 2:40
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    @DavidLively - Your assumption of the exhaust being pressurized and not having a chance to suck in anything is inaccurate. It's basically an effect where as exhaust passes over the open area of the crack, it will draw air in with it. This extra air gives a false lean and the computer compensates by dumping more fuel. There's a name for this effect and I don't remember what it is (I don't think it's the same as a venturi effect, but along the same lines). Sep 24, 2016 at 12:03


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