2006 D 2.9 TCI-J3 Engine Engine Control P0087 Fuel Rail/System Pressure - Too Low
Auto repair and Study guide Component Location
General Description
Auto repair nad Study guide At Commom rail diesel engine, rail pressure regulator is controlled based on rail pressure sensor signal in order to maintain optimum rail pressure according to current engine rpm and load.
however when a trouble, which leads rail pressure to out of target value intended by ECM, occurs due to mechanical or electronical reason, ECM shuts engine down and sets DTC by limiting fuel (stops injector operation) in order to prevent engine from being controlled abnormally. "rail pressure monitoring error" is the DTC which diagnose 1).supplying state of low pressure fuel and 2).mechanical operating conditions of high pressure pump and rail pressure regulator indirectly based on rail pressure sensor output voltage and rail pressure sensor duty. thus, repair relavant to this DTC requires mechanics the total understand of fuel system
DTC Description
When rail pressure is lower than target rail pressure, ECM tried to raise rail pressure as decreasing fuel press. regulator current(increasing fuel supplied to common rail). If meeting real fuel pressure to target pressure is failed to achieve, P0087 is set.
When this code is set, check possible causes which decrease fuel pressure such as 1)close stuck of fuel press. regulator, 2)lowered efficiency of high press. pump, 3)fuel leakage, 4)excessive returning quantity of fuel from injector, 5)clogged low press. pump filter.
DTC Detecting Condition
Auto repair and Study guide
Detecting Condition
Possible Cause
Threshold Value
● Rail pressure is below target value but FPRV correction quantity is above specified value.
● FPRV stuck
● High press.pump poor performance
● Fuel leakage
● Excessive fuel returning quantity at injector(Refer to "Component Inspection" of P0263 for checking process )
● Low press. fuel poor supply
Stuyd guide Fail Safe
● Engine turns OFF after time delay.
● Knock sensor signal is ignored(MDP learning inhibited)
Check lamp
