RPM drop and temperature drop

Jan 5, 2019
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Any sifu can advice:
Took out battery for a week after horn suddenly go berserk..
After put back the battery, the car engine rpm seems like dropping to below 500 rpm when car going for a complete stop, like stop in front of traffic light.
When gear in P or N, the rpm is normal.

And the other thing I notice is the temperature is a bit low... Anyone experience before?
 

Izso

Boooooossst
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Izso

Boooooossst
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Mar 28, 2004
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Any sifu can advice:
Took out battery for a week after horn suddenly go berserk..
After put back the battery, the car engine rpm seems like dropping to below 500 rpm when car going for a complete stop, like stop in front of traffic light.
When gear in P or N, the rpm is normal.

And the other thing I notice is the temperature is a bit low... Anyone experience before?
Question : Is your car completely stock?
 

sanekit

1,500 RPM

sanekit

1,500 RPM
Dec 9, 2015
1,611
156
163
Petaling Jaya
nothing to worry about coz u remove the battery for a week. like what @vr2turbo said, just drive around for a few days and adjust the idle if it's still low. if the stepper motor problem, your rpm will drop during cold start. my guess is the TCU and ecu was reset hence u see the rpm drop when in D. u can check the tcu rpm idling in D with a handheld obd device. some workshop can even adjust it for u.
 

^pomen_GTR^

7,000 RPM
Senior Member

^pomen_GTR^

7,000 RPM
Senior Member
May 13, 2010
7,510
1,688
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The Mines
Any sifu can advice:
Took out battery for a week after horn suddenly go berserk..
After put back the battery, the car engine rpm seems like dropping to below 500 rpm when car going for a complete stop, like stop in front of traffic light.
When gear in P or N, the rpm is normal.

And the other thing I notice is the temperature is a bit low... Anyone experience before?

need to do ecu relearn..

normal after removing battery
 

sweelt

2,000 RPM

sweelt

2,000 RPM
Nov 6, 2016
2,255
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163
Penang
the ECU and TCU does relearn after take off battery. but sometimes it doesnt, there's a idle screw at throttle body in case you need to increse idle..
good TS car back to normal. idle screw kinda help if adjust bit by bit but don get used to it.
ECU always read rpm and compensate by ISC. Careful or it take you round 360 degree.
 
Last edited:

vr2turbo

Beyond 20,000 RPM!
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vr2turbo

Beyond 20,000 RPM!
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May 11, 2010
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good TS car back to normal. idle screw kinda help if adjust bit by bit but don get used to it.
ECU always read rpm and compensate by ISC. Careful or it take you round 360 degree.
Like my old car, cold idling higher, warm up normal, hot lower......:banghead: