Engine starts then cuts off - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

cents109 · 11-24-2009, 10:42

Have a 1999 F-150 pickup 5.4L Trition engine.

The engine will start but cut right off. If we keep our foot on the accelerator at about 1,000 rpms, we can keep it running. But as soon as we lift off of it, it cuts off. Put a brand new battery in it since the old one was 10 years off (stock). Let the computer reset itself over night. The truck started right up, drove it most of the day. Let it set for about 4 hours, then tried to go somewhere, and the problem started all over again. checked all fuses and they were fine. checked belts and they were fine.

This problem started about 3 weeks ago doing exactly the same thing. I told my husband when getting it inspected, the gargare man cleaned the post of the battery. When he (husband) looked at them, he did the coke trick. Pour coke on the post, and the truck started right on up. ran it for a couple of days then the problem occurred again. Tried the trick once again, wouldnt stay started but I could keep it at 1,000 rpm at all times to get me home. That is when we got the new battery. Then problem came back.

Any suggestions on what could be the cause?

Thanks

**Bert** · 11-24-2009, 11:55

Try cleaning the IAC (ISC) valve. The PCM may be trying to set the idle with it and it isn't working. Also, if you go to Autozone, they will check the codes (if any) for free.