Re: Rod ? for you, Re: engine jerk (archive)

"The bucking at low RPM transition of closed to open throttle can be reduced by adjusting the throttle switch so the throttle is shut when the switch closes" - I get this with my car, really annoying in slow traffic. Abrupt enough transition to jerk the whole car. How exactly do you improve this?
Thanks, Sheldon
e28 M5 76k

Adjust the throttle switch(black w/3 pin connector) on the front of the #1 cylinder throttle body. The switch needs to be adjusted so that when pressure is put on the throttle rod you can hear the switch "click". When you release the throttle rod pressure the switch will "click". The adjustment is critical because of the throttles open to wide before the switch opens the engine will buck and if the switch is adjusted too close to throttle closed the switch will not close reliably. The idle speed setup can also affect the throttle transition from closed to part throttle. The idle is set by disconnecting the throttle switch and bridging the three pins in the cable connector. Then adjust the idle to 850 RPMs (large brass screw in the center of the middle throttle body). I use an averaging tach meter to help average the engine RPM fluctuations when in open loop idle. Reconnect the throttle switch after setting the idle manually and the engine will idle in closed loop with the Idle Control Valve(ICV) in the correct position to do all the other functions the ICV needs to do.

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yikes. Seth 12:54 6/27/2001 (0)

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