Hard Upshift When Accelerator Pedal Is Released

CAUSE/REMEDY:
Pressure build-up too slow when accelerator pedal is released.
1. Disconnect secondary vacuum consumers from transmission side of vacuum system.
2. Check vacuum controlled exhaust related components.
3. Check performance of vacuum pump and routing of vacuum lines.
4. Install a restrictor of 0.6 mm dia. in the line to connection VCV on vacuum pressure convertor.

NOTE: Install the restrictor on naturally aspirated diesel engines only.