P1550moderate severityPowertrain
Idle Speed Control Error
on 1996 BMW 318is E36 1.8L I4 · RWD
What this code means
The DME detected that the engine idle speed is outside the acceptable range and cannot be corrected by the idle speed control system. The engine speed deviates from the target idle RPM by more than the allowable margin.
Symptoms
- Rough or unstable idle
- Idle speed too high or too low
- Engine stalling
- Check Engine Light
Common causes
- Vacuum leak
- Dirty throttle body
- Faulty idle air control valve
- Incorrect base idle setting
- Air intake leak after MAF sensor
Diagnostic steps
- Check for vacuum leaks with smoke machine
- Clean throttle body
- Test idle air control valve
- Perform idle adaptation with scan tool
- Check intake system for leaks
Repair notes
Repair vacuum leaks and clean throttle body; perform idle speed adaptation.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1