Should have used Fuel additive
Just picked my truck up from the shop. It was having to spin more and more to start this past year. After that it ran great but the slow starts were starting to worry me. I'd heard that we should us...
Forum Discussion
Grit dog wrote:
Scott, that's very unusual I think. I don't know anyone who's lost a cp3, ever I think. And we all run the same fuel.
Are you certain it was not just injectors?
Failing IP wouldn't run strong, low fuel pressure. Hard cold starts but runs fine are classic injector high return rates. IP can't make enough pressure to trigger the injectors with high returns when cold, but once it kicks, the IP can keep up.
Well should run like a top again.
Did you have lower injection pressure than commanded?
I agree. The CP3 does not control the injection events like the old non-common rail pumps did. All the CP3 does is send a certain amount of fuel at a commanded pressure to the injectors and they control injection events. Hard starting, but running fine after warmed up is indicative of an injector failure on a common rail, not IP failure. A failing common rail IP would run poorly and continue to run poorly due to not being able to pump at the desired pressure.
When I worked at Cummins, we had many fleet customers ignorantly blame fuel system failures on lack of lubrication in the fuel pump. After digging trough the system in our labs, it was found that contamination damaging the injectors was the culprit in most cases. Come to find out, most were not adhering to the recommended fuel filter change intervals or their onsight fuel tanks did not have proper breathers on them to allow condensation to escape. Water then contaminated the fuel which damaged injector tips when compressed. Lubricity of the fuel(even ULSD) had nothing to do with it in most cases even though their technicians swore up and down that it did. They shut up as soon as we shown the data from the lab.
