1981 Honda Prelude Automatic TransFACTORY OEM SERVICE PROCEDURE

All Models (Engine Hot)

  1. Complete "Dashpot System Check" as outlined previously.
  2. Bypass the speed sensor by applying battery voltage to yellow/black wire at throttle opener solenoid connector.
  3. Raise engine speed to 3500 RPM and release throttle. Engine should return to idle in less than 6 seconds, but not faster than dashpot check time.
  4. If return time is less than check valve time, remove vacuum line from throttle opener solenoid valve to throttle control valve. Feel for vacuum at throttle opener solenoid.
  5. If vacuum is present, replace throttle control valve. If no vacuum, replace throttle opener solenoid valve. If return time to idle was more than seconds, replace throttle control valve. After component replacement, retest system and remove jumper wires.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

Rather have a pro handle this?

A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.

Comes to youSame-day available12-month warranty
Get a Free Quote

No obligation. See pricing before you book.