My Father-In-Laws 1999 F250 is running very rough. We had it scanned using a Snap-On Solus scanner. The code that came up was for the IDM. Where is the IDM located? If the truck has a chip in it (we are not sure) and the chip fails, will this throw the IDM code?
What is a good source for an IDM (aftermarket or used)?

 

Two more questions, is the IDM the same as the injector pump? Secondly, can I tell from the VIN number if the vehicle was produced before/after a certain month? In pricing parts, some parts suppliers needed to know if this was an "early 99" or "late 99". How do you tell? Thanks!
OzarksFord

 

The IDM is the computer that runs the injectors.
It is located inside the driver's side fender well, you need to remove the inner fender cover to see it.

Our trucks don't have an injector pump, the IDM is simply and electronic module dedicated to actuating the injectors.

You need to remove the chip and have it scanned again for codes.
REMOVE THE KEY FROM THE IGNITION WHEN YOU REMOVE THE CHIP, PCM OR IDM.
Unless you want to pay for a computer as well.

12/98 and BEFORE is an early 99
After 12/98 is late 99.

If your truck was manufactured in December, you'll want to check some other things to be sure, and we can help you do that.

 

Its most likely the under valve cover harnesses. The IDM is several hundred dollars and usually isn't the culprit. The harnesses will throw the IDM codes. You can buy new harnesses from International way cheaper than from Ford.

 

When i changed my gp's, i threw an IDM code. I thought i may have blown something up. I took apart the valve cover again and one of my connectors were off by like a 1/4" if that. Check the UVC connector.

 

What Fat Diesel and John311t said. I did the same thing last time I was under the valve covers and it set the p1316 IDM code. No codes were set for injector open circuits at all. I would have been off on a wild goose chase had I not JUST HAD the valve covers off and it ran perfect before I took them off. #1 injector was unplugged and I had to go back in and fix the problem. OOPS.