SPONSORED LINKS

RPM's fluctuate

Tiny
MNT8092
  • MEMBER
  • 2001 FORD MUSTANG
  • 117,000 MILES
My car runs perfect except for at a red light after forty five minutes of driving the rpm's fluctuates 500 to 900 rpm's. Almost everything has been replaced. It drives me crazy. I get thirty two miles on the highway. I have another car same model/year and same engine and it does not do that. Thanks if you can help.
SPONSORED LINKS
Monday, March 5th, 2018 AT 2:50 PM

3 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,797 POSTS
Good morning.

There is an Idle air control valve that keeps the idle steady. Have you looked at this yet?

Roy
Was this
answer
helpful?
Yes
No
Tuesday, March 6th, 2018 AT 5:11 AM
Tiny
MNT8092
  • MEMBER
  • 2 POSTS
Yes, I have replaced everything. I am wondering if it could be my brake booster. Nothing leaking.
SPONSORED LINKS
Was this
answer
helpful?
Yes
No
Tuesday, March 6th, 2018 AT 12:33 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 47,663 POSTS
It sounds more like you have a dirty throttle bore and IAC motor. Here is a guide to help you see how to fix it:

https://www.2carpros.com/articles/throttle-actuator-service

Please let us know what happens.

Cheers, Ken
Was this
answer
helpful?
Yes
No
Thursday, March 8th, 2018 AT 12:37 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

Sponsored links