97 F150, Hard Start when Cold

My F150, 5.4L 60k miles started to have problems starting when it's cold. It will start right up, then shortly die. Starting it again will cause the idle to raise and slowly drop, it will continue to run like that. It seems very rich out the tail pipe, if put in drive before a 2 minute warm up it will not accept gas, but rather pretty much die. After the 2 or some minutes it will run much better and accept throttle. After the truck has warmed up it will restart without problems until it cools again 4-5 hours later. It is performing this problem with great repeatability, each morning it is hard to start.

I took it into my favorite repair shop, it has never set a code or displayed the light. The shop was also not able to see any sort of error codes displayed. They verified fuel pressure, the o2 sensor, the TPS, the Mass Flow sensors reads fine but they are not 100% sure about it and don't want to start swapping parts. They checked and cleaned the EGR. The shop is not sure and is sending me to the Dealer. After the truck warms up fully it runs much better, seems a bit low on power in the low end.
It even pinged the other day at freeway speeds when throttle was applied. Short of the starting and a slight loss of power it runs quite and smoothly. Had a coil go out 6 mo ago, this was much different. I also suspect mileage is going to be very poor, but I have not driven that many miles, nor refilled the tank.

This problem pretty much showed up over night, one day ran very well and the next poorly. This did happen the day after it was refilled with gas and this was my first thought and why I drove it for a few days before taking it to the shop. However the fact it restarts just fine when warm has pretty much ruled out bad gas for me.

I have been pooring over the post on the web, the only one I found that really fits my problem well is the possibility of a sticky idle air control valve. This was on a 96 and I am not it even applies to 97.

1) Any ideas that the shop or I might double check before I head off to the dealer?
2)Can I check the idle air valve (Where is it) if I have one?
3)Gas?

Thanks
Ron

More than likely it is the Idle Speed Control motor. These are a common failure on ford. It should be located on the throttle body. It is a round valve that is about 3 inches long and has 2 8mm headed bolts that hold it to the throttle body, There is one electrical connector and a hose that is about 1 inch in diameter. You can remove it and clean with spray cleaner and try it to see if that helps. If it does, you can replace the part or wait till it acts up again. If it doesn't help, nore than likely the valve is bad.

There is a valve looking item that I think is what you describe. It is located to the back of the engine connected into the throttle body area. There is a mounting plate attached to the throttle body that has a 1" diameter hose that is connected before the throttle body. This valve mounts onto that plate at a 90 deg angle. This is all under the firewall on the truck, I also discovered how deep the valley in the center of the engine as I dropped the racket. I removed the valve or what ever item it was and cleaned it the best I could with spray carb cleaner. It has two holes or ports on the mounting face that are approx .5" diameter. Does it sound like I got the right item?

Unfortunatly cleaning didn't seem to make a difference. Would this cause the engine to run lean at higher RPM's? It is pinging badly at freeway speeds up any sort of grade, and noticably low on power. Just wanted to double check before I get a new valve.

Thanks for the help.

You have the right valve. Hoewver, the pinging you stated, sounds more like a ditry Mass Air Flow sensor. It is located in the air inlet tube behind the air filter housing. Use an electronic parts cleaner to clean it. It is held on by 4 torx heades screws. They might be tamper proof(raised dot in center). There are 2 real small wires with resistors in them on the sensor. Be really careful not to damage them. Electronics cleaner will dry rapidly and leave no residue. Good luck.