Engine accelerates when brake is applied

Partial cars are still in the infant stage and there will be problems at the point where the CPU has to decide wether to power up and charge the battery or run on a dwindling battery supply. The cars are designed to charge the battery off the brake application so on long down hill runs with the brakes applied the energy is converted to charge the battery and it will be at this point if the battery is nearly flat that the CPU is hesitant to start the engine or rely on the charge from the brakes. I would think that there will be a huge learning curve before you get the hang of it. However having said all that , I would think a trip to a service centre to check it out might be in order.

Further information will be required unless you would nlike a simple solution like.
Step one start said vehichle
Step 2 apply foot ti brake pedal and put gear selector in drive
Step 3 remove foot from brake pedal to accelerator pedal
Step 4 apply presure to accelerator pedal untill desired speed has been acheived
Note these steps will not work for manual transmission see section 37

For braking see section 22

Click the link below to troubleshoot this problem: ---
Car loses power while acceleration? http://schematicsdiagram.blogspot.com/2011/12/car-loses-power-while-acceleration.html

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Loss of acceleration?

http://technoanswers.blogspot.in/2012/02/loss-of-acceleration.html

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Acceleration lag problem?

http://repairhelpcenter.blogspot.com/2012/01/acceleration-lag-problem.html

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How exactly the Vehicles Accelerator Cable works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-cable.html

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How exactly Vehicles Accelerator Pump Diaphragm Works?

http://repairhelpcenter.blogspot.com/2011/11/how-exactly-vehicles-accelerator-pump.html

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accelerator pedal sensor?

http://technoanswers.blogspot.in/2012/02/2009-chevy-impala-accelerator-pedal.html

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stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

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Engine accelerates when brake is applied?

http://technoanswers.blogspot.in/2012/02/engine-accelerates-when-brake-is.html

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This will help.

Thanks.

This sounds like a bad brake booster, that sounds like the hissing is when brake is applied. check the booster . thats why the engine sutters when brakes are applied, the booster starts to leak vacuum, thats where iwould start. good day

apply brake and accelerate engine while vehicle is standing still, you need to apply brake hard, DO NOT do this for a period of more than 1 minute or you will be putting alot of stress on your transmission. you will be trying to set off the "check engine" warning lamp or the "service engine soon" warning lamp, and get a misfire failure code, after code sets on your vehicle computer, get it scanned it will tell you which engine cylinder is misfiring ie "P0301= cylinder #1 misfire" then check out spark plug, spark plug wire and ignition coil. one of them is probably causing this.

Have your mechanic check the brake booster. I have had this problem one time before. the booster wasn't working correctly, small hole in the diaphram. it acted as if there was a large vacuum leak letting the engine rev up, but only when the brakes were applied.
Randy

Are the engine rpms climbing when its jerking forward? seems like it could be a Transmission torque converter problem.

Probably a disc brake pad scraping on a warped rotor as it goes around. When you apply the brakes the warped rotor causes the car to pulse or shake as the rotor goes around and applies the brake unevenly. You need a front brake job.

You have a serious vacuum leak affecting the engine and a brake proble, -The connection between them is the brake vacuum assist and the brake master cylinder. The brake master cylinder is the target componant. Change it out and other related problems should be resolved. Good Luck &be safe-Ned

Hello and my name is john and i will be helping you to day.

Q.

Occasionally your 2001 pathfinder will accelerate when the brakes are applied. And there is a very loud squealing of the tires with the lunching of the car.

A.

Your pathfinder has a TPS sensor which is your throttle position sensor if this sensor is stuck or bad it will send a MSG to your computer saying that it's not getting enough fuel so it will compensate and cause your engine to rev unusually hi and causing your tire's to chirp also your apm's should jump while doing that you should se a big difference in your gas mileage as well.