Delibes

After searching and browsing all kinds of cluster-related topics, I still have not found a solution for my problem. I have just put a new battery, power steering pump, starter and timing belt in a 1990 LS400.

Shortly after putting the starter in, my Lexus had the following issues: the car will idle normally but the tachometer needle will shake at idle at around 2,000 rpms. Pressing the gas pedal will make the needle drop dramatically and then skyrocket back again. The engine/tranny will stumble only once, a few times, at speed (55-70mph). Tapping the brake pedal will actuate the TRAC-OFF light momentarily. Finally, the car stalled when I pushed the brake pedal fully on an off-ramp. It started right up, ran perfectly and drove home.

It seems pretty obvious that this is an electrical problem, but I cannot locate it. I checked the wiring harness behind the trunk door hinge and it seems fine. Has anyone had these symptoms? What should I do, where else should I look for the cause of all these little issues?