Fuel Pump Wave Forms

The wave forms below, represent the fuel pump armature condition on a 206 XS TU5jp4. The red wave is the original pump and the green wave is a new pump. Note the difference in amperage between the old and new and also the cyclic abnormality in the wave. The ECM was complaining of a fault code reading 'Low fuel level' (ignition misfire). No 'P' codes, but I interpreted this as a lean misfire, although unsure how it could know this. After replacing the pump, the fault code did not return.


The wave forms below, show the supply voltage and the holding current for the fuel pump stop solenoid, on a DW8 engine. The Blue wave is the current trace. As you can see, it is very low current.

Stop solenoid

Last Reviewed: 27 March 2016Copyright © 2004...2016 Mark Stammers