Engine Performance - Correcting Poor Idle Quality
03.1-05DATE
7/95
Sedan Range
MODEL
1995-96 MY
4.0 NA
VIN
720001-ON
Valve Timing Changes - AJ16 Engine
ISSUE:
To improve idle quality, revised camshafts with reduced valve timing overlap were introduced on the normally aspirated engines as running change 95/13. The original camshafts, with a maximum opening position of 110 degrees have been superseded by camshafts with a maximum opening position of 114 degrees. This change is accomplished by machining the camshaft slot in a different position. The valve timing overlap is reduced from 22 degrees on the 110 camshafts to 14 degrees on the 114 camshafts, Illustration 1.
The maximum opening position of the 114 intake camshaft is 114 degrees after top dead center (ATDC) while the maximum opening position of the exhaust camshaft is 114 degrees before top dead center (BTDC).
The 114 camshafts were introduced for a period, withdrawn, and then reintroduced as a permanent change.
The table lists the change points by engine number as shown.