Hey guys, this bus has had fault code 559 come up 2 times in about 2 weeks. FAULT CODE 559 - (ISC and ISL) Injector Metering Rail 1 Pressure - Data Valid But Below Normal Operating Range - Moderately Severe Level. The first time it came up the bus was low on fuel and had the low fuel light on. But now this time it is at half a tank. I started following the troubleshooting guide on INSITE but the links for specific tests do not work. It doesn't appear to have any fuel leaks and passes the leak test. Not sure where to go from hear. Any ideas?
which tests? If its the same as what ive been dealing with I think youre supposed to check the quantity of fuel that returns over time from the manifold toward the rear of the head. To do this youll need special tools. I made the banjo tool easy enough and have the fuel rail port cap on order. if this is what you need to do i can point you in the right direction.
I have had that code come up a couple times and both times ended up the clear plastic bowl on the fuel separator leaking at the filter. Easy check is to make sure it is clean (there may not be any sign of fuel leakage at this time) and using the primer pump it up until unable pump anymore, and then check for leaks.
It appears to have been a while since the fuel filters have been replaced(I just started a few months ago and haven't got to replace everything yet)and I was wondering if I could be just fighting a filter plugging up. The next test I was at was checking the low pressure system check. I am fairly new to diagnostic work, the last district I was at had 2 other mechanics that handled these things. It wants me to check inlet restriction, gear pump pressure and pressure drop at filter.
Replaced both filters. Upon replacing the fuel/water separator I found some black "jelly" in the plastic bowl. I cleaned it out, do I need to do anything else? Is this just an indicator of lack of maintenance or something worse?
scot1337 Black jelly sounds like an issue we had few years back. I was a break down in the biodiesel, the grease had separated. I didn't think we had biodiesel here but when we call our fuel delivery company they informed us that all diesel in Georgia was 10% bio.
2008 BB w/ISC Fault Code 559
Posted - 05/18/2017 : 11:04:04 AM
