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When driving, sometimes when I want stop the vehicle, I go to press the brakes, but that time engine rpm goes high, keeping brakes pressed hard, after 5 second engine becomes normal. It goes high when rpm is more than 2000. I changed tps, air idle control valve, control valve of EVP, fuel pressure sensor, no leaks, detect no diagnostic codes on obd. Please what is the reason? Thank you.

  • Does the engine speed increase when you press the brakes or when you release the accelerator? – Keith Oct 26 '15 at 2:34
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This situation could be Transmission Flare. The engine control briefly ups the RPM to match the transmission downshifting, to prevent an abrupt downshift feel. If the control or sensing systems are out of whack, it can overdo the RPM adjustment.

Some of the items you replaced require adjustment or calibration. For example, the Idle Air Controller (a prime suspect here) requires some settings, just bolting it in might make the problem worse.

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There is possibly a vacuum leak which can affect the performance of your vehicle by creating a lean condition. Additionally the extra oxygen will increase the combustion temperature and potentially damage your valves in the cylinder head.

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