Same story.....Won't start

[JTinFL]

Hey guys, long time lurker, first time joining and posting. I pretty much have the same story as a lot of people on here. I have had my 99 F250 7.3 for a while now and only have had one issue. I love this truck and it tows tons of weight like it isn't even there. The truck would just miss about once every 5 hours of driving and when it did the rpms would drop around 500 rpms. I replaced the CPS and that took care of that.

Now, 6 months later, truck is running completely fine and I have it there idling when it kinda bogs down and then runs normal again. About 10 minutes later, it bogs down again and completely stops running. Now there were no other signs of it doing anything wrong. I changed the fuel filter on it, it has oil, has oil pressure when trying to start (according to gauge on dash), it has rpms when trying to start, both batteries are good, frame fuel pump is running fine, the WTS light is completely normal, and it is throwing codes 1316, 0478, 0340, and 0470. I checked on those codes and two of them are exhaust backpressure related, one is the CPS, and one is the generic IDM code from what I can tell.

I guess my question would be, what would be the order in which I should start checking things. It seems to me that it is pointing towards the IDM but that is the most expensive thing to start replacing. I just moved to a new town and don't have any friends here with trucks yet so swapping parts will be difficult.

I am having the truck towed to my workshop tomorrow morning to start messing with it. I guess I will pull out the IPR first, then unplug all the wiring and check voltages/clean up terminals, pull the valve covers, and leave the IDM for last??

Any other suggestions would be great. Also to add, if anyone is in the Fort Myers area and has a scanner that will read high pressure and do injector buzz test, I will pay you some money to swing by tomorrow to save me a lot of time and labor.

Thanks guys!!!

[BLOWINSMOKE99STROKE]

Originally Posted by JTinFL

Hey guys, long time lurker, first time joining and posting. I pretty much have the same story as a lot of people on here. I have had my 99 F250 7.3 for a while now and only have had one issue. I love this truck and it tows tons of weight like it isn't even there. The truck would just miss about once every 5 hours of driving and when it did the rpms would drop around 500 rpms. I replaced the CPS and that took care of that.

Now, 6 months later, truck is running completely fine and I have it there idling when it kinda bogs down and then runs normal again. About 10 minutes later, it bogs down again and completely stops running. Now there were no other signs of it doing anything wrong. I changed the fuel filter on it, it has oil, has oil pressure when trying to start (according to gauge on dash), it has rpms when trying to start, both batteries are good, frame fuel pump is running fine, the WTS light is completely normal, and it is throwing codes 1316, 0478, 0340, and 0470. I checked on those codes and two of them are exhaust backpressure related, one is the CPS, and one is the generic IDM code from what I can tell.

I guess my question would be, what would be the order in which I should start checking things. It seems to me that it is pointing towards the IDM but that is the most expensive thing to start replacing. I just moved to a new town and don't have any friends here with trucks yet so swapping parts will be difficult.

I am having the car towed to my workshop tomorrow morning to start messing with it. I guess I will pull out the IPR first, then unplug all the wiring and check voltages/clean up terminals, pull the valve covers, and leave the IDM for last??

Any other suggestions would be great. Also to add, if anyone is in the Fort Myers area and has a scanner that will read high pressure and do injector buzz test, I will pay you some money to swing by tomorrow to save me a lot of time and labor.

Thanks guys!!!

Try these few things:

For cps code, try putting a new one on (again), if it doesnt fix it atleast you have a spare, i know i and many others on here have spares.

For EBP code, the sensor for it is on the front of the motor its mounted to the plate where the HPOP shaft is located. That plate is held on by 2 bolts, no need to remove it just saying that for identification purposes. check it and the tube connected to it. maybe try cleaning it before replacing it, it is kinda expensive.

It could be your IPR, or injection pump, it could be a bunch of stuff but with those codes thats where id start.

If all else fails call ED aka Junior from Griffin Diesel Performance, in Sarasota. There is a guy coming up from the fort today for our DYNO day, maybe you can come meet the crew if youd like. Junior's number is 941-809-8543 he will give ya some tips, and if worst case senario hell boogie down there with a Gooser and drag you back to his shop.

[JTinFL]

Hey thanks man. I actually have a shop that I am opening up in Fort Myers. I have years of experience in turbo design and gas engine performance cars. Diesel trucks are a whole different animal. This is my first truck and I am learning all about the differences between the two (and the costs!).

I guess I will just get the truck up there and start playing around with things. It is stuck sitting right in front of my enclosed trailer right in the storage yard due to it not starting.

Thanks for the help, I will see what I can figure out because the girl planned on us taking out the boat tomorrow and no truck = no boat.

[JimTJr]

Wire the EBV OPEN, that way if it is pulling closed on you you elmiminate that possibility. (The code, or sensor won't cause you any running issues, UNLESS the EBV is closing... Like a choke, only in reverse, the exhaust can not exit the motor) As he said, maybe get a new CPS if not for a spare. I have carried a spare one since they were over 100.00 each. And never needed it yet..... Now they are much more reasonably priced.

Your IDM code is MOST LIKELY the under valve cover harness, the IDM rarely goes bad. But a short/open wire in the harness plug will cause an IDM code. I would pull the valve covers and inspect the plugs closely. (Only about an hour job,,,) And either replace the harness' or see if the plug is loose. (You may need the locking clips from FORD)

[JTinFL]

Ok cool. Thanks! I got the truck back to my shop now so I will be able to work on it with real tools. I will pull the valve covers off and clean everything up. I think I will make sure the lifters are torqued down to spec too cause its a loud one. Hopefully I will be able to figure it out today so the girl doesn't try to kill me.

Thanks again guys. I will update once I figure it out.

[BLOWINSMOKE99STROKE]

any update?

[JTinFL]

Well, I haven't had a lot of time to mess with it but I pulled the valve cover and everything looks good. The way it happened, I am pretty sure that its the IDM. I am putting it all back together and going to have someone with a nice scanner to come by and read some diagnostics on it. Hopefully I will be able to figure it out really soon.

[fun2drive]

If it is not your CPS I vote for your IDM. By the way the place on eBay has them for like 259.00. I bought one there from a forum member suggestion and my truck must have had a failing IDM as my fuel mileage is now up close to 20 mpg all the time. I too pulled the valve covers and put the new harness wedge in to no avail and if I had believed my code reader it said IDM all along as well as EBV too which I think is an artifact. My truck ran but poorly and with high EGTs until replaced.

I think the IDM I got was from some place close to Tampa like New Port Richey or close to that area. I called up vs buying directly on eBay to talk to a real person since I have an early 99. Got the right IDM, they knew exactly what I was talking about and sent the unit out right a way.

[JTinFL]

Very cool. My gas mileage had been really bad when I am not towing and around 10 with around 12,000 pounds so I figured that was decent.

The best I could get with no weight is 15mpg.

I have a guy bringing a scanner over to plug in today and I will hopefully know exactly what has failed.

Still leaning towards the IDM though. Thanks for all your help and any chance of still having the contact number for the guy in Tampa for the IDM. I would drive up there today and get it so I could put the boat in the water tomorrow and save the weekend! Thanks.

[JTinFL]

It was the IDM. Plugged a scanner into it and it immediately told us what it was. Thanks for all the help guys.