Reply to thread

Message: [QUOTE="Derek@Vision Diesel, post: 1248148, member: 344"] Figured some of you may be able to save us some time if you have seen this before... 2003 F350. Wont fuel up to its potential, mostly high RPM issues. Currently running 225/100 and an S371 with a DieselSite high flow HPOP. This truck does have a 4r100 with a stand alone as well, which I am wondering if this could be part of the issue. Nothing from the factory transmission harness is plugged in expect for the transfer case. We are still running tunes that require the MAF sensor. -4.8v+ of ICP - 63psi of fuel pressure at all times - 48-50psi of boost shown through an edge sending unit - Idles great, spools amazing, launches very hard The bad - MAP only shows 20-22psi maxium a. Has a brand new Motorcraft sensor, did not change b. No boost leaks - We can only log 2.2ms of PW through the OBDII port, which quickly falls to 1.8 during a run - Back pressure monitored on the Edge CTS2 is at 0. We cannot get a reading and never have been able to get a reading on back pressure, even with a brand new sensor. It just will not provide a signal to the OBDII port. When the truck has 190s and a stage 3 it would trap out at about 110mph consistently. Felt strong throughout the run and honestly ran about how I would expect from that setup. With current setup... Still runs strong and as you would expect, there is just not the gain in power that we should have seen. In fact going by the numbers, we lost power going to the 225s and 371. This would totally make sense if ICP or fuel pressure were suffering now with the larger injectors, but they certainly aren't. We have verified this numerous times. We have tried Gearhead straight PCM tuning and then we also tried PHP's PCM/FICM programming. Almost an identical result from both tuners taking very different approaches to it. Anyone with some tuning knowledge have a suggestion as to where a guy should start from here. It has to either be a limiter in the tuning tables or a mixed signal from a sensor/lack there of on the truck. [/QUOTE]