sometimes When AC on Bumbaba rpm/idle (400-500) ang normal idle 800 when ac on

**alyx1705** · October 7th, 2009 10:27 AM

up... Help po sa may mga alam.... T_T

**v6dreamer** · October 10th, 2009 06:54 AM

The idle solenoid seems to have failed. This keeps the RPM up while there is load on the engine at idle. Have the car scanned for codes to be sure or it could be an electical power drain, the A/C is drawing more power than the car can provide. It could be that your Generator is not working as it should, or the A/C is faulty. Check them all out.

**alyx1705** · October 10th, 2009 01:21 PM

Thanks for the reply, i already brought it to nissan quezon avenue about a month ago and they did an aac overhaul but still after a week my idle drops again, Is it possible that it is my alternator? nung pinacheck ko din sa AC expert sabi servo daw yung problem wala sa aircon. ngayon I'm thinking saan ko pwede ipacheck lahat ng sinsabi mo, nagdadalawang isip nako sa casa eh, I don't even know if na overhaul ba talaga nila ung aac valve. Napansin ko din na kapag mainit na ung engine saka magloloko, i mean, kapag nakapag drive nako for about one hour or pagmainit na engine tapos pagpinatay na makina then inistart uli parang walang power pero normal ung idle 700-800 tapos paginopen ung aircon biglang mag drop na ung idle 400-500. but if walang aircon ok naman idle nya. my alam ba kayong magandang shop at magaling? matagal ko ng problem to eh. TIA..

**v6dreamer** · October 12th, 2009 06:04 AM

Oh boy, your car is much more serious than I thought.
Head gaskets are there too make an air tight seal and keep the compression you build inside the piston chamber. If there is a leak in the gasket you will loose compression and overall power. So if you feel you are lossing power then you probably have a bad head gasket. Not always the case though. A compression test should be the easiest way to find out if your head gasket is bad or not. You have to get the piston to the bottom dead center and the proceed to have it go to TDC (top dead center) to get an accurate reading.

Try answer Y or N:
Was A/C working properly? Is it blowing cold air, no clunkly noise on the compresor other than engine died out when turn on the A/C?

Is this happened when you were at idle only?

Is this happened when you were at rate speed(driving)?

**alyx1705** · October 13th, 2009 12:54 PM

nissan already replace the head gasket, and i think it's not the head gasket but if you prefer to test it,how will i test it?...

Yes A/C is working properly, its blowing cold air, There was no clunky noise, engine wouldnt die it only reaches up to 500-300 but when its about to die i press the gas pedal together with the brake, so i use my two feet to have thenormal rpm.

no, When i Shift to drive it actualy goes down 500-400rpm.

When im driving and pressing on the gas pedal my rpm is good but while im about to stop specially in traffic and stoplights and pressing the brake, the rpm will eventually drop again to 500-400 like the engine stalls. It's like when ac on the normal idle is 400-500 but the real normal idle of my car would be 750-900 right??
what seems to be the problem? i think this happens only when my engine is already warm and i started it again, the rpm would drop to 400-500 , but when in cold start my idle is normal when ac on.