Uneven Mustang Idle
courtesy of Bob, The Auto Answer Man
My 1990 Ford Mustang GT 5.0 runs great without the Air Conditioner on. With the AC on it often dies when I come to a stop. The idle is usually at 700 rpm but drops to 550-600 when I turn on the AC. Also, I can notice power surges while driving at steady speeds, again, only while the AC is on.
I cleaned the idle air control valve and the problem is still there. Do I need to replace the control valve? I've recently replaced the PVC, plugs, cap, rotor, fuel and air filters, as well as the battery cables. Although these parts needed replacing they did not help the unstable idle with the AC on. Can you help me?
Your map sensor may also be malfunctioning. It seems, since you are also getting a problem while driving with the A/C, that the car does not recognize the increased load of the A/C. The MAP (manifold air pressure) sensor is what tells the motor how much load the engine is seeing.
Bob, The Auto Answer Man
Debt is preventing me from taking a vacation this year or the vacation I'd like to take this year! Tell us: Yes, debt is affecting my vacation plans! or No, we're going exactly where we want to go but we'd love to learn make our trip as inexpensive as possible!
Have a car care question? Visit our automotive center and see if we've already answered it or a similar question.
More Money-Saving Tips for Your Home
- Should I use a HELOC for home remodeling and repairs
- Find the best mortgage rates in your area
- 3 ways to use a mortgage calculator
- Mortgage calculator: Calculate your payment and more
- Home equity calculator: HELOC vs. line of credit
- How much can additional payments save me on my mortgage?
- Who offers the most home insurance discounts?