RPM

Tiny
KAIKIING
  • MEMBER
  • 1994 TOYOTA COROLLA
  • 176,535 MILES
May I know is that normal for my car when start up the RPM is going up slowly from 0 to 1000rpm no matter early in the morning or daytime?I've found that other car when start up the rpm will go up quite fast like a speeding then drop back to around 1000rpm. If that is not normal then what might be the problem of it?Please advice.
Thursday, October 6th, 2011 AT 11:45 AM

7 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,055 POSTS
When the engine starts, it should go quickly to idle. You could have issues with the idle air control valve, a vacuum leak. If the check engine light is on, have the computer scanned to identify trouble codes. Most parts stores will do it for free.
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 11:51 AM
Tiny
KAIKIING
  • MEMBER
  • 44 POSTS
My car cannot scan with scan tools. Only can use check engine light and get error code 32 relate to MAPP sensor.I've change the MAP sensor but seen no much changes with it. Already clean the IAC valve and also the throttle body. But still with same result. Should I change the whole throttle body?
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 11:57 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,055 POSTS
No, I don't feel that will help. Have you checked for vacuum leaks?
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 12:14 PM
Tiny
KAIKIING
  • MEMBER
  • 44 POSTS
Most of the vacuum tube I've change with new one cause dont have idea how to really check for the leaking. The engine not really idle too when the air-con is on most of the time but sometimes it's idle.
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 12:22 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,055 POSTS
Go to our homepage under the DIY section for directions on how to check for vacuum leaks. Check around the intake as well as hoses.
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 1:21 PM
Tiny
KAIKIING
  • MEMBER
  • 44 POSTS
Can you please give me the link?Thanks
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 1:45 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 110,055 POSTS
Here is the one they have. I will check because there is a much more involved process. I know it was written because I wrote it.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
Was this
answer
helpful?
Yes
No
Thursday, October 6th, 2011 AT 6:00 PM

Please login or register to post a reply.

Related Engine Revs Up Content

Idle Air Control Motor Replacement
GUIDE
Idle Air Control Motor Replacement
The idle air con­trol mo­tor or idle speed con­trol mo­tor is de­signed to ad­just the air flow into the in­take man­i­fold at en­gine idle. En­gine idle speed is mon­i­tored by the PCM...
VIEW MORE