I recently picked up a 94 Mustang 5.0, 5 speed. It ran fine until last night. At idle, the RPMs hang around 2,000. If I rev the RPMs to 3,000+ it'll still only back down to about 2,000. It has about 136k miles on the odometer, everything is stock and original.
I checked vacuum and I'm getting about 20-21 pounds of vacuum, so I don't believe I have any leaks. I unplugged the IAC and it made no difference. I plugged the IAC connector back in and unplugged the TPS and the RPMs climbed a little.
I've been searching this forum over and over again and found the idle reset procedure. I'm going to try and reset the idle tonight. Is it reasonable to believe that the idle would just randomly need to be reset on a stock Mustang that hasn't even been tampered with?
I'm thinking the IAC is probably stuck open but I don't want to just pull the trigger on a new IAC unless I know for sure it's bad. Ford dealer wants $180 for a new IAC, I can get one from rockauto.com for about $100.
Any thoughts/suggestions?
I checked vacuum and I'm getting about 20-21 pounds of vacuum, so I don't believe I have any leaks. I unplugged the IAC and it made no difference. I plugged the IAC connector back in and unplugged the TPS and the RPMs climbed a little.
I've been searching this forum over and over again and found the idle reset procedure. I'm going to try and reset the idle tonight. Is it reasonable to believe that the idle would just randomly need to be reset on a stock Mustang that hasn't even been tampered with?
I'm thinking the IAC is probably stuck open but I don't want to just pull the trigger on a new IAC unless I know for sure it's bad. Ford dealer wants $180 for a new IAC, I can get one from rockauto.com for about $100.
Any thoughts/suggestions?