BMW 530D 2.9 2000 - Hesitation under full load #Archived Message
Posted by Ray Mahon on October 19, 2009, 11:09 pm
Hi All, New here so easy on me for the first post!! Have the above car in with no fault codes, this has come from another garage who have replaced both fuel pumps for a non start issue. They had also managed to knock off the vacuum accumulator (beside turbo) piping and rerouted the boost solenoid wiring so that it shorted on egr piping. Once this was rectified car drove fine and no fault codes stored, returned to customer. Week later car back in with hesitation, basically under load will pickup fine but at times this slight hesitation occurs. It also sometimes idles roughly and can give a single metallic "click". Anyways no fault codes, boost press, and fuel rail press. stay close to desired while fault occurring. I have scoped FRP sensor and control solenoid, solenolid pulse and current seem fine but press. sensor voltage plot shows multiple oscillations between 0.7v and 4.5V lasting only few milliseconds. I'm thinking (hoping) that it is an issue with pressure control solenoid sticking but would appreciate any ideas? I have the pico *.psd file if anyones interested. Regards Ray