QuestionI have a 1991 Ford F-150. She's a trooper, but is causing me headaches lately... There are two questions, really... The longest lasting issue is the beginning idle. When I start the truck, the idle is very unsteady, I have learned that I can't drive her until a normal idle is achieved, or I'll be left stranded until she feels like starting up again, which usually takes a few hours. Sometimes I can get the proper idle by revving the engine a few times, sometimes that doesn't work. It can take anywhere from a minute, to 20 minutes until I am able to drive. I have tried to fix this several times, to no avail. I have had my truck in to 4 different mechanics, none can fix it. Someone has got to know what is wrong!!! The newer problem is that when I am driving and the rpm's start to even out, the whole truck vibrates, usually around 35 mph. My mechanic buddy told me it could be the spark plugs, wires, cap and rotor, but all that except the wires was just changed a couple weeks ago, so I changed my wires today, and still, no change... PLEASE HELP ME!! Oh, and this truck was my dad's, and it sat in the garage, not being driven, for about a year and a half until I bought it from his widow... Not sure if that helps or not...
AnswerCasaundra,
I don't know what has been done to your truck by the mechanics, but I would start by cleaning the throttle body and idle air control valve thouroghly using gunk foamy engine bright. Remove the air intake and spray it on a rag then clean inside the throttle body. Next remove the IAC motor and fill it with the cleaner and let it soak. Rinse and do it again.
Has anyone checked for codes such as TPS sensor or coolant temp sensor?
Let me know what you find.
