Hello Everyone!
Great site. I have a '99 4.6, with 70,000 miles, original plugs. Below 15°F, truck will not start unless I plug in the block heater. I have read about the IAC, if this is not a IAC problem, is this related to some sort of a sensor? Could it be some kind of a coolant sensor?? I was told I might need to change the plugs to improve the gap on cold weather starts. Thanks for all your input in advance for I am going to a ~Superbowl~ party GO BEARS!!!!!!!!!!!!!

 

Is it a crank and no start or a no crank no start? Go Colts

 

Start with the basics of starting: Fuel, spark, and air. Change your filters, plugs, and wires.

 

New battery, electrical system is fine. Cranks - strong but no start. When I plug in the block heater after a couple hours the truck starts real strong. What is causing this? Thanks again!

 

I have a 99" 4.6 and mine starts, but REALLY don't want to, let me know if cleaning your IAC or new plugs works for you? I have 88,000 and may need a tune up as well.

 

Crack your throttle slightly while starting. if this corrects the symptom, your IAC is sticking closed.

A very common occurrance on Fords this time of year.

Check the easy stuff first.

Steve

 

hello, i also have a '99 but w/ a 4.2L and 142,000mi on it. my problem is not that it won't start, although it is a bit sluggish in the morning w/ temps in the single digits but when it does start i hear a relatively loud tapping, almost knocking sound. this noise does go away once i've warmed the truck up for a good 15 minutes? what could this be? any suggestions?? thanks for the help

 

I had a similar problem earlier in the year, it happened a few times, and the truck would not start at all. I starting giving the throttle a thump on the second try and the truck started right up. I've been a bit more religious with the gas line antifreeze for the rest of this season . . and I havent had a problem. Even though we've had some even rougher days than the day I had the original issue.

 

My truck is doing the same thing. As long as the throttle body is manually cracked open via the pedal, it will run. As soon as you let off, the engine dies.

 

Just reporting back on the situation in which was discussed above.
Cleaned the IAC as needed, and the old turd is back up and running like a champ.

 

Thank you all for you're input.Ihave not been able to get on line to much lately.Yes,i am leaning towards the IAC ,because when i hold the pedal down a bit as stated before cranking, the truck fired up on the first try.I am planning to change out the IAC,I'll let you know what happens,thanks again.