Working on a 97 f250 that we installed a 96 E250 engine into. While the engine was out we resealed the engine, deleted the fuel bowl and installed a DIY
regulated return. We also deleted the mechanical fuel pump and replaced it with a 6.7 fuel system with a 2006 fuel tank sumped. We ran 1/2 lines to a y at the engine feeding the back of the heads and being regulated returned at the front of the heads.
The issue we are having is the truck starts and runs fine, but at about 2500rpm ( while in idle or driving) it stumble/misfires like clock work at that RPM. While researching we found/thought that we found the issue, apparently the E250 run AB injectors which are technically Cali style injectors. So we removed the injectors out of the original engine that the truck had which were AAs and installed them into the van motor. Prior to installation we replaced the injector cups and injector orings.
The engine still stumbles at 2500 rpms. We have swapped IDMs with some known goods ones we have laying around, we have swapped CPS
(grey 3 dot) and a black CPS
( brand unknown) and we still have the stumble.
We have also swapped PCMs with a know to be good PCMS.
I have a new Snapon SOLUS EDGE and access to an IDS, while looking at the PIDS and based off the research found they all look to be within spec i;e ipr
and so forth.
We did a compression test on a warm engine yesterday and today. Yesterdays test was done while the engine was warmed up and todays were done on a cold engine. These were the numbers:
8 cranks warm engine
8 cranks cold engine
5 cranks repeated 3 times cold engine
1 400 400 400
2 400 400 390
3 400 400 410
4 390 390 390
5 400 380 380
6 400 400 400
7 400 400 400
8 380 380 380
Truck has passed the CCT on IDS and the Solus. The truck also passes the buzz test with all injectors sounding the same. The codes that we have gotten are :
P0476 Exhaust Pressure Control Valve ( we have deleted the EPCV on the pedestal so Im assuming thats why that code pops up.)
P0713 P0713 Trans Fluid Temp Sensor A Circuit High Input (this is a code that has been intermittent. Im assuming since we have the trans cooler bypassed at the moment that that could be the reason. ) Does that code cause the truck to go into limp mode?
Another thing, the fuel pressure is rock steady on the regulated return gauge at 55psi. It maintains that pressure during the stumble as well. Im pretty confident its not fuel related but I have been wrong once or twice in my life lol.
I really need to get this truck on the road. This is my brothers truck and its going to be his college vehicle. We only have about a week and half time frame to get this done.
Where do we go from here? I would really appreciate all the feedback possible.
At this point we are purchasing a DU87 CPS
and we are also considering swaping out the ICP
for some known goods ones.