Hi Folks, I have a 99 2.2L 4 cyl Camry. I had a low idle speed problem earlier that whenever I started the car, the idle speed was very low (about 500 rpm) and I had to press the gas pedal once to make the rpm up to about 3000 to "stimulate" the car, then the idle speed became normal (about 1500 rpm at cold). To resolve that problem, I cleaned up the throttle body and idle air control valve, changed spark plugs and pcv valve. After that, the original low idle speed issue seems to be addressed since now whenever I start the car, the idle speed is normal (about 1500 rpm at cold) and it will stably stay around 900 rpm after the engine get warmed up. However, a new issue comes out - Low & Rough Idle When I Apply Brakes. It happens only when the engine has been warmed up and gear is put in R or D (P and N are OK). The idle will drop to about 500 rpm and become rough (up and down). In this case, if I release the brakes and press the gas pedal, I can feel the car lacks of power (seems to be very heavy and move very slow). So I have to give more gas and the rpm will go crazy to about 4000 rpm (but the car still move slowly). Does anyone have any idea what may cause this problem? Thanks!

 

Check the power assist brake booster for air leaks.

 

Thanks Joey! I don't know where it is. Is this one (see attached image)?

 

That's it. The can type item having a large hose attached.

Disconnect the hose and plug it. Then determine if the engine runs OK when the brake is pressed.

 

Thank you Joey! I will give a try.

 

Great, post back with the results.