Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSGMC1992PICKUP K2500, 2D PICKUP, 5.0 H, AUTOMATICREPAIR AND DIAGNOSISENGINE PERFORMANCEENGINE CONTROLS - ADJUSTMENTSIDLE SPEED & MIXTUREIDLE SPEED & MIXTURE (GASOLINE)CONTROLLED IDLE SPEED CHECK
1992 GMC Pickup K2500, 2D Pickup, 5.0 H, Automatic
Controlled Idle Speed Check
1992 GMC Pickup K2500, 2D Pickup, 5.0 H, AutomaticSECTION Controlled Idle Speed Check
- Ensure no trouble code(s) are present, IAC system has been checked and ignition timing is correct. Block drive wheel and apply parking brake. Connect scan tester to ALDL connector with scan tester in "Open Mode".
- Start engine and bring to normal operating temperature. Check for correct state of Park/Neutral switch on scan tester. Check if idle speed and IAC valve pintle position (counts) are as specified. See CONTROLLED IDLE SPEED & IAC COUNT .
- If idle speed is not within specification, refer to TESTS W/O CODES article in this section. On 7.4L engines, perform MINIMUM IDLE SPEED ADJUSTMENT. See MINIMUM IDLE SPEED ADJUSTMENT (7.4L ONLY) heading below.
CONTROLLED IDLE SPEED & IAC COUNT
| Application | Idle RPM | (1) IAC Counts | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2.5L TBI | |||||||||||||||
| "S" Series | |||||||||||||||
| A/T (2) | 800 | 15-40 | |||||||||||||
| M/T (3) | 900 | 5-20 | |||||||||||||
| 2.8L TBI | |||||||||||||||
| "S" Series | |||||||||||||||
| A/T (2) | 800 | 5-20 | |||||||||||||
| 3.1L TBI | |||||||||||||||
| "U" Series | |||||||||||||||
| A/T (2) | 600-700 | 5-15 | |||||||||||||
| 3.8L PFI | |||||||||||||||
| "U" Series | |||||||||||||||
| A/T (2) | 650-750 | 16-20 | |||||||||||||
| 4.3L CPI | |||||||||||||||
| "L" Series | |||||||||||||||
| A/T (2) | 625 | 5-50 | |||||||||||||
| "M", "S" & "T" Series | |||||||||||||||
| A/T (2) | 550 | 5-40 | |||||||||||||
| 4.3L PFI Turbo | |||||||||||||||
| "S" & "T" Series | |||||||||||||||
| A/T (2) | (4) | 1-50 | |||||||||||||
| 4.3L TBI | |||||||||||||||
| "C" & "K" Series | |||||||||||||||
| A/T (2)(5) | 537 | 5-30 | |||||||||||||
| A/T (2)(5) | 650 | 20-35 | |||||||||||||
| M/T (3) | 550 | 2-20 | |||||||||||||
| "G" Series | |||||||||||||||
| A/T (2) | 538 | 5-30 | |||||||||||||
| M/T (3) | 650 | 5-30 | |||||||||||||
| "L" Series | |||||||||||||||
| A/T (2) | 625 | 5-50 | |||||||||||||
| M/T (3) | 600 | 3-30 | |||||||||||||
| "M" Series | |||||||||||||||
| A/T (2) | 538 | 5-30 | |||||||||||||
| "P" Series | |||||||||||||||
| A/T (2) | 650 | 20-35 | |||||||||||||
| 5.0L TBI | |||||||||||||||
| "C" & "K" Series | |||||||||||||||
| A/T (2) | 500 | 5-30 | |||||||||||||
| M/T (3) | 600 | 5-30 | |||||||||||||
| 5.7L TBI | |||||||||||||||
| "C", "G", "K" & "P" Series | |||||||||||||||
| Under 8500 GVW | |||||||||||||||
| A/T (2) | 525 | 5-30 | |||||||||||||
| M/T (3) | 600 | 5-30 | |||||||||||||
| Over 8500 GVW | |||||||||||||||
| A/T (2) | 550 | 5-30 | |||||||||||||
| M/T (3) | 600 | 5-30 | |||||||||||||
| 7.4L TBI | |||||||||||||||
| "C", "G", "K" & "P" Series | |||||||||||||||
| A/T (2) | 750 | 5-30 | |||||||||||||
| M/T (3) | 800 | 5-30 | |||||||||||||
|
|||||||||||||||
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
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.