More Automotive Answers
Question Library
Ask a question about Automotive
Volunteer
Experts of the Month
Expert Login
Awards
About Us
Tell friends
Link to Us
Disclaimer
|
| |
|
|
| |
| | | |
About Sean Halliday
Expertise
general auto repair,japanese,bmw,mercedes,mini cooper 1960/2009,general british cars,ford.I DO NOT work on automatic transmissions.Manual transissions i install clutches only.Many people ask me to diagnose noises from their cars,unfortunately i cannot do this unless i hear it.As you appreciate,vehicles can and will make a variety of noises.I DONT UPGRADE or fit aftermarket performace kits,parts,chips,only replacement parts.
Experience
40 years experience on all general auto repair.
| | |
| |
You are here: Experts > Industry > Transportation and Logistics > Automotive > ford pickup
Expert: Sean Halliday - 11/10/2009
Question
QUESTION: Hello Sean, i have questions on 2 differnt trucks, both 1994, the first one is a gas that when it is cold the idle is about 2500 when it first starts ,after 15-20 seconds it idles down. i have changed the air valve and it didnt fix the problem. i can unplug the air valve and it will have a very slow idle.on the second truck it is a diesel and when it sets a few days it wont pick up the fuel with out using starter fluid, what would cause the fuel pressure to disappear when setting.would an electric fuel pump on the rail frame help this problem. i have been using start fluid even in warm weather. thanks Don
ANSWER: Diesels i do not work on and the other problem could be a vacuum leak making the idle rise too much.If you unplug the IAC and the idle settles it may be a clue that the valve needs replaced.
---------- FOLLOW-UP ----------
QUESTION: Hello Sean, I changed the tps today and it didnt help will check for vac. leak soon. when i unplug the new air valve the engine will not start with the throttle in idle pos. it would start with the old valve in idle pos. and run about 500 rpm. Do you know where the voltage source comes from that goes to the air valve. Thanks Don
Answer
The voltage source will be from the pcm.I would test the vacuum with a gauge before you buy anymore parts.The high idle could also be a leak at the intake manifold gasket and a test will confirm this.The tps i meant was on the diesel and not the gas truck.
Add to this Answer Ask a Question
|
|
