How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Mike V. Your Own Question
Mike V.
Mike V., Auto Service Technician
Category: Ford
Satisfied Customers: 25191
Experience:  25 years experience on all makes and models, Licensed NYS Inspector.
Type Your Ford Question Here...
Mike V. is online now
A new question is answered every 9 seconds

Engine revs when you first start it up then idles back down,

Customer Question

engine revs when you first start it up then idles back down
JA: Will the headlights turn on? Is the battery fully charged?
Customer: yes
JA: What is the model/year of your Ford?
Customer: 2005 escape 3.0 engine
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: yes replaced vacuum hoses and fuel filter
JA: Anything else you think the mechanic should know?
Customer: just changed all spark plugs and coil paks about 3 months ago
Submitted: 10 months ago.
Category: Ford
Expert:  Mike V. replied 10 months ago.

HI there,

How high does the engine rev?
How long does it stay up there?

Customer: replied 10 months ago.
10-20 sec
Expert:  Mike V. replied 10 months ago.

How high do the rpms go when it does it?

Customer: replied 10 months ago.
Expert:  Mike V. replied 10 months ago.


First, it's fairly normal for the engine to jump up in speed on first start although this seems a little bit high to me.

Usually when this happens it's a result of either the mass air flow sensor or the IAC. I would try cleaning the IAC (idle air control) motor. This is mounted to the top of the throttle body and held on with just a couple screws. Sometimes it gets sticky and can't adjust properly.. I actually owned one of these for a while myself. Take it off and clean it up inside with some carb cleaner, then reinstall it. Do not turn the key on while you have it off the throttle. If it fixes the problem you can continue to drive it with the old cleaned one. I was able to get another 80k out of mine without a problem.

If it doesn't solve the issue. Then try unplugging the mass air flow sensor before you start it and see if it stays under 3k, if it does, then replace the maf sensor.

Please let me know what more I can do to assist you today. Also, please remember to rate my answer, Just Answer does not compensate me for my time and resources. Follow up questions are included in the price of your question. If you are using the free trial, or have a subscription a rating is still required.
Thank you so much!

Expert:  Mike V. replied 10 months ago.

Hello again, I haven't heard back from you so I thought I would find out if you needed further assistance with this?