Re: This erratic idle will be the end of me!!!
Posted by nas90 on December 30, 2002 at 09:07:38:
In Reply to: This erratic idle will be the end of me!!! Please help!!! posted by Jed Pineda on December 29, 2002 at 22:54:01:
1998 Disco has (presumably) twin spark 4.0 litre Rangie engine? Presumably your vehicle is US spec?
On earlier NAS90 and Disco I engines, Stepper motor controls idle. Valve on fuel rail controls fuel rail pressure at high fuel requirements (acceleration/ Freeway speeds).
On my NAS 90 (MY1995 3.9 Disco I engine with coil) I made the mistake of removing the stepper motor complete with its mounting and gasket, rather than (as I found out when cleaning) that you can unscrew the stepper motor leaving the mounting and gasket intact.
However, having taken the complete assembly apart it was obvious that the cork / paper gasket had shrunk due to heat and was partly covering the vacuum pipe which goes to the fuel rail valve. If you have not removed the mounting then try this. If you have, although you have replaced with new stepper motor did you clean where it mates on manifold?
Check and clean all the various electrical connections and lubricate / protect with silicone / electrical grease. If you have clean air blow out connections.
Was the AFM exactly the same was there no leaks good connection?
