Date: Sat, 19 Dec 1998 10:56:01 -0500 From: "FRANK VAN HASTE" <frank.vanhastenopsam.net> Subject: Ideas Needed: RPM Hunting at Idle
The car in question is a 1989 900, nicely broken in at 104,000 mi. When driven energetically then brought down to idle, the RPM will "hunt" between about 800 and 1400 at maybe 20-25 Hz. Also, on occasion during extended highway jaunts the "Check Engine" light will come on -- intermittently at first, then steadily. There is no discernible effect on performance. I am imagining either (a) a failure in the electronic engine control ("computer") or a problem with a sensor in the engine control system. Any ideas on what might be the problem, or how to trouble-shoot, before I subject myself to the tender mercies of the dealer's service department? TIA, Frank Van Haste frank.vanhastenopsam.net ----- "Heavier-than-air flying machines are impossible." -- Lord Kelvin, President, Royal Society, 1895. ----- http://pages.cthome.net/frank.vanhaste 203-261-8514