ZL Fairlane Intermittent Idle
To give you a brief history outline:
The Fairlane had a small engine fire due to a misfire in the system. The fire was located on the top of the intake manifold and according to the mechanic the engine was able to be gotten going again by just cleaning it and replacing the hose between the airflow meter and the manifold which had been damaged. ie the fire was small.
After getting the car back I replaced the old worn out engine with a reconditioned long motor. The installers fitted the same EFI hardware and sensors, non of this equipment was changed. After the installation, the PCV valve was replaced as the car was running very rough. With the new PCV valve the car runs at about 90% but still has some intermittent idle problems which are very annoying.
The symptoms are:
On start up the car idles OK. After driving for a few minutes and you stop at lights the idle will jump up and down from say 300 to 700 rpm, it may occasionally stall in this position. Continuing driving the car exhibits surges and periods of lack of power can be felt in the car. After a few further minutes of driving the car will operate normally. During extremely warm days (40degC) the car is less stable and the idle problems can be felt much more regularly.
To date I have taken the car to several mechanics and changed the following items without fixing the problems:
1. PCV Valve
2. Hall Sensor in dizzi
3. Ignition Coil
4. Ignition Module on dizzi
Can anyone suggest where to look next???