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 MANUALSBUICK1989SKYHAWK S/E, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCESYSTEM2.0L(K)/2.5L TESTS W/CODESDESCRIPTIONCODE 35 - IDLE SPEED ERROR (2.5L A, N BODY)NOTES
1989 Buick Skyhawk S/E, Standard
Code 35 - Idle Speed Error (2.5L A, N Body): Notes
1989 Buick Skyhawk S/E, StandardSECTION Notes
Code 35 will set when closed throttle engine speed is 150 RPM greater or less than correct idle speed for 20 seconds.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- Continue with test even if engine will not idle properly. If idle is too low, "Scan" tester will display 80 or more counts or steps. If idle is high it will display zero counts. Occasionally an erratic or unstable idle may occur. Engine speed may vary 200 RPM or more up and down. Disconnect IAC. If condition is unchanged, IAC is not at fault.
- When engine was stopped, the IAC valve retracted (more air) to a fixed position to provide increased airflow during next engine start. During next engine start, a "Scan" should display 100 or more counts.
- Disconnect IAC valve prior to this test. The test light will confirm the ECM signals by a steady or flashing light on all circuits.
- Test verifies faulty IAC, short to voltage (steady light) or poor IAC connection.
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.