1987 Chevrolet Forward Control 4.8 T, StandardFACTORY OEM SERVICE PROCEDURE

Fuel Injection System - TBI: Identification

The throttle body injection identification number is stamped on mounting flange, on throttle lever side. See Fig 1. Alphabetical code letters are stamped on the throttle body at external tube locations to identify vacuum hose connections.

All Astro, Safari and "S" series vehicles use either the model 220 or model 700 TBI unit. The "R" and "V" series use the model 220 TBI unit. All "G" series vans and "P" series trucks use the model 220 TBI unit.

Fig 1: Throttle Body Identification Location
G10509Courtesy of GENERAL MOTORS CORP.
Factory Service Tools

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When to See a Mechanic

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

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

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