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Engine power hesitation 850 1994

Well, this vehicle is like playing Whack-A-Mole; every time I fix something another problem surfaces.

The car runs pretty well. Cleaning the entire intake system made a big difference. See 'Stinky Exhaust' for the backstory.

Now, acceleration is 'weird'. The engine revs up smoothly but seems to have power lags. And it's cyclic. Holding the throttle steady, the engine has little power, then good power, then little power and then good power up past about 3200 RPM where it seems to even out to good power.

I would guess vacuum problem, but can't locate a leak. Any ideas??








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    Engine power hesitation 850 1994

    Could it be the AC compressor kicking on and off? That really had an effect on my 850T. Try it with the AC off.

    Klaus
    --
    Common sense trumps a PhD








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      Engine power hesitation 850 1994

      As much as I wish it was the AC, it's not. Just drove around with it turned off.

      Without moving the gas pedal, the engine will in turns act throaty & powerful and then act subdued. It's a little more than subtle. I can live with it, but worry that something's about to go...








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        Engine power hesitation 850 1994

        Check around the vacuum tree for leaks or cracked elbows. It sounds like the ECU is getting mixed signals from the front O2 sensor, which happens when unmetered air comes into the manifold.

        Klaus
        --
        Common sense trumps a PhD







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