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Would it be possible for a fuel pump to push extra volume through the injectors with fuel pressure still staying in spec? This system has a returnless PWM pump.
Non-Flex Fuel as far as I can tell. No stickers in the engine bay, or in the gas gap area. I also don't see any alcohol sensors in the fuel lines. I know the GM FFV's have the alcohol sensors, not sure about Ford's though. If the computer thinks it has E-85, and you really have pure old fashioned hydro carbons I can see how the system would run rich.
Tacitus043 wrote: Would it be possible for a fuel pump to push extra volume through the injectors with fuel pressure still staying in spec? This system has a returnless PWM pump.
I'm gonna be honest, I'm not sure. :silly: But, my gut instinct and (limited) understanding of hydraulics says no. If the pressure is in spec, and the injectors are correct for the application, then the pump flow has to be correct.
Speaking of, has anyone replaced injectors? :huh: I ask because I went down this road on a BMW recently. Guy replaced all six 'just for maintenance', and ended up introducing a huge rich condition. Didn't mention that when he brought it in, OR that the injectors flowed far more fuel than the originals.
Tacitus043 wrote: Would it be possible for a fuel pump to push extra volume through the injectors with fuel pressure still staying in spec? This system has a returnless PWM pump.
I'm gonna be honest, I'm not sure. :silly: But, my gut instinct and (limited) understanding of hydraulics says no. If the pressure is in spec, and the injectors are correct for the application, then the pump flow has to be correct.
Speaking of, has anyone replaced injectors? :huh: I ask because I went down this road on a BMW recently. Guy replaced all six 'just for maintenance', and ended up introducing a huge rich condition. Didn't mention that when he brought it in, OR that the injectors flowed far more fuel than the originals.
The injectors were replaced in the very beginning. When this customer first came to the shop with this rich condition, before any real diagnostics were done, I pulled the part number off his injectors and found it did not match his 04 VIN number. After some research I found Ford did have some changes in it's fuel system for that model year, 04 also being a year shared with an older body style. I told the customer that he should put the correct injectors in to match his PCM calibration before we started going down any diagnostic rabbit holes. The customer changed the injectors himself, but the issue remained. As far as I can tell the injectors are the right ones for that year, but who knows at this point. Almost everything drive train related in this truck has been worked, and re-worked on before it ended up in my bays. I am shop number 7 at this point. Luckily this customer has been the very definition of patience and graciousness. At this point the job is not exactly a money maker, however I am determined to make this vehicle right.
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