1988 Ford F150 V8 5.0
Bought the truck a week ago. The previous owner said that it had an idling problem. I towed it home and first put in a new battery. After the installion of the new battery the truck fired right up. I drive it for 10 miles and I put it back into my garage. I then came back two days later to start the truck up to smog it and it would not stay idle. The idle would surge and smoke would pour out the exhuast. i would then try to restart the truck without any luck. This time the truck would not even start for more than 5 seconds. I can hear the truck fire, but it would not maintain an idle. I changed the cap and rotor, and fuel filter. The cap looked corroded and thought it might work. - Nope. I then checked to see if there was spark @ the end of the spark plug wire. Yes there is spark during the ignition switch in the start position. A nice blue spark. I think I need to test the fuel system now. Can anyone give me a step by step process? Or give me any inside on the problem i am describing. If you need anymore info, I can suppy it. The Chiltons Manual does not help too much.

 

maybe a fuel pump?

 

>maybe a fuel pump?

I just tested the intank and external fuel pumps. I did this by removing the inlet hose to the external pump and switched the ignition to the "on" position. The internal pump pumped 2 seconds worth of fuel on the floor. I then turned the ignition off replaced the hose and made sure the external pump turned on and it did. I'm ruling out bad fuel pumps. The fuel pumps still may not function after the 2 second initial pump because it is not receiving voltage to make it work. hummmmm???

 

 

Pull the codes. At this point in the game I like TPS or 02 sensor, but I reserve the right to change my bet LOL. Also clean the IAC

SEE THIS:

http://www.off-road.com/ford/bigbroncos/tech/eec/index.html