If the stock wastegate was stuck open, would the car go rich?
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If the stock wastegate was stuck open, would the car go rich?
If the stock wastegate was stuck open, would the car go rich?
I'm just wondering how the Impreza ECU handles fuel mixture...
Hypothetically, if the wastegate on the turbo is stuck open, and effectively all the exhaust gases are bypassing the turbine, would the stock ECU still be able properly maintain the fuel mixture even if the engine is revving over the 4K RPM range?
I'm just wondering how the Impreza ECU handles fuel mixture...
Hypothetically, if the wastegate on the turbo is stuck open, and effectively all the exhaust gases are bypassing the turbine, would the stock ECU still be able properly maintain the fuel mixture even if the engine is revving over the 4K RPM range?
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I'm not 100% sure on this.....anyone feel free to correct me if I'm wrong....but the ECU would not be able to compensate enough for that situation. The more likely scenario would be that the ECU will go into "Limp mode" so you can get the car to a safe place to pull over. Technically, if you were revving at 4k with a stuck wastegate, your car would obviously not be building boost, and the ECU would probably freak out because @ 4k your maps are set to dump "X" amount of fuel for "X" amount of boost +\- Y%. Hope that makes sense. and if not.....I'm sorry, I'm not thinking to clearly right now.
-Ted
-Ted
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If the wastegate was stuck open then you'd run wastegate boost, and no more. This is about 7PSI on a stock WRX. Everything would run fine, just low boost. No fueling issues; this essentially has nothing to do with fueling.
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mmboost is right... You would see very low boost, but the a/f ratio would still remain reasonable. The ECU uses the MAF sensor to measure the amount of air being inducted and calculates fueling based largely on that signal. So if you're running less boost, the MAF sensor is measuring less air entering the engine, and thus the ECU reduces the amount of fuel injected resulting in an appropriate a/f ratio.
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Jan 14, 2008 09:37 PM
