kylebgt

Ever since I bought my gt it has had a eratic idle. It only happens everynow and then but when it does the tach bounces from 800-700 rpm's back and forth, over and over until I give it a little gas which sometimes solves the problem. It has 80k miles on it, do you guys think that I just need to replace the spark plugs or is it something more serious? Any help would be appreciated. thanks

fishyducky

try cleaning the IAC

bransdaman78

700-800 maybe nothing... bad gas

mylongvictor

Do you suspect an Aftermarket Computer tune that tuned the care for premium gas? Cuzz thats what happened to mine. The Computer was tuned for 93 octane but the bastard that had the car never took it off before he sold it. So I was filling regular the first 2 weeks and my car sounded like she was choking all the time. I took her to the dealership and had the computer reset to factory settings. That solved the problem.

red mustang gt 46

REPLACE the IAC, cleaning it is hit or miss...

JPGT_00

dont bother cleaning it, just go buy a new one, 50 bucks from autozone, or advanced, cleaning if it works is just a short term fix to a problem every mustang owner has

Deannostang

Replace IAC and clean MAF (mass air meter) sensor wires with electrical contact spray cleaner. Both items can contribute to rough, inconsistent engine performance. The next time you fill up your tank, add one of the better carbon removal gas treatments. Valvoline Synth Power is one of many that work well. Just be sure it is a fuel "system" cleaner and not just a fuel "injector" cleaner. One other thing to possibly change is your fuel filter. It should be changed no later than every 15,000 miles to ensure smooth running.

Lord Ryan

I was having a similar problem. After I did all of the other stuff that has been suggested, I changed my plugs. That fixed it for me. My plugs were five years old though.