Hi gang, I have finally been able to pull a code from my truck. 96 F-250 4X4. 460/E4OD. The code is Eng Mem Code: 212. It states that the IDM input to PCM Spout signal is lost, circuit grounded. What does this mean? I have had these recurring problem with vehicle falling on its face. Dumping fuel in exhaust. Exhaust manifolds soaked, (not water either). I have changed numerous sensors with no relief in site. Upon using scan tool i noticed that while driving the computer would cycle from "Open Loop to Closed Loop". Is this possilbe? I thought a vehicle would run under Open loop condition only when engine is cold? Once operating temperture is reached the computer would switch to "Closed Loop Operation" and stay there?

Sensors that have been replaced: ECT, ACT O2s. Sensors that checked ok: Map, IAT, and TPS. These items fell with in limits so i didn't replace them. Engine has no vacuum leaks with 21" of HG at idle. Sorry for such a lengthy post but thought all info would be important.

Any info on what to look for would be greatly appreciated. I would like to keep this truck, but its getting frustrating when there is no solution to be seen in site. Dealer would basically do same as I in hooking a scan tool to port and record engine functions while driving. If i have overlooked something let me know. I'm STUCK!!

thanks,
Xaviar

 

Id suggest following the diagnostic routine for that code , I dont have any OBD II diagnostics . What scanner did you use ? Did it not point you in the right direction ?

 

> Id suggest following the diagnostic
>routine for that code ,
>I dont have any OBD
>II diagnostics . What scanner
>did you use ? Did
>it not point you in
>the right direction ?

I used a Actron code scanner. Fully digital with different cards available for what vehicle you're working on. Being my truck is a 96 the OBDII system was not a production item with my engine combination. I have the EEC-IV system on my truck.

The scantool only pointed out the fault. (I posted the fault in my first message). "Probably need a better scantool than what I have"? Upon talking to a dealer a hour ago he said the code means the truck is running under a cold condition. He also said the EEC-IV system is one of the hardest to debug. I think he's right! None of the manuals I have here mentioned this. I have since order the factory service manuals to correctly diagnosis this truck. I have checked VREF on ground straps and some sensors. Everything comes back at .5volts so far. Much more to check tomorrow. 18 degrees outside right now...........burrrr

 

The IDM , Ignition Diagnosis Monitor usually deals with ignition related problems ...What exactly has the problem been ? How many miles on the truck ?

 

> The IDM , Ignition Diagnosis
>Monitor usually deals with ignition
>related problems ...What exactly has
>the problem been ? How
>many miles on the truck
>?

The symptoms have been (driving/sitting at light)very rough idle, only able to drive about 10-15 mph when occurs. the smell of fuel inside the cab and exhaust manifolds wet if I let run over 4 minutes. raw fuel coming from tailpipe. Sometimes if I shut the truck off and let set for 3-5 minutes and restart, the truck will run like nothing has happened. This may happen a couple times a day or I may drive the truck for a couple of weeks with no symptoms at all.

When the truck is running ok i do have about a 10 to 20% reduction in gas mileage. Only averaging around 280 miles per fill up. I used to get around 340.

The truck has 84K on it. Mostly highway miles.

Xaviar