1999 F-150 Won't start

start
trucks
#1

I have a 1999 Ford F-150 that will turn over but will not start. It has done this a few times over the past couple weeks, but all I had to do was pump the gas pedal a few times and it would start right up. Now it won’t start even after I give it gas. What could be the problem?

#2

Pumping the gas pedal on a fuel-injected engine will not do anything at all. You can try starting it while holding the pedal half-way down. If it starts this way, your problem is probably the idle air bypass valve (called the IAC on most cars). This is not an uncommon problem for Fords from the mid 90’s to the mid 2000’s.
The other use of the gas pedal while starting a Fuel-injected car would be to hold it all the way down. This sets the computer into clear-flood mode and turns all fuel off. If it was flooded, you would do this for a little while and then release the pedal and re-try the starter.
(In the old days, pumping the pedal on a carburetor would pump extra gas into the intake manifold.)

#3

Is the IAC easily replaceable? I have 1 final left for school then I was planning on heading home. I don’t exactly have the means of working on my truck here at school as it is parked on the side of the road and I have no tools. Would it be advisable to try and start it up with starting fluid just so I can make the 2 hour drive back home and take it to my mechanic there?

#4

First, if it won’t start with the gas pedal pressed down 1/2 or 1/4 of the way, then the IAC is not your no-start problem. If it is, then on the V8’s I have dealt with, it was a very easy part to change. Two bolts, one gasket, one two-wire connector, and one hose (not clamped).
As to making it home, if it is the IAC, you can probably hit it a few times with a hammer and unstick it for a few days. (That’s worked for me.)

#5

Hitting it worked like a charm! Thank you very much for your input. One more thing though, now that it is unstuck, is it still in need of being replaced?

#6

My experience says yes. You can clean the carbon out of it, and it will go longer before sticking again. The replacement part is a new design that doesn’t let the valve close all the way, so it is much less likely to ever stick. It was about a $60 part a few years ago, I don’t know what they run now. I’m glad to have helped.