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.
Engine Controls
Computer commands are carried out by solenoids, motors and other control devices. Solenoids are used to control vacuum, air bleeds, the carburetor fuel flow, etc. Motors are used for the idle speed control and mixture adjustments.
Some computers control functions directly, while others use indirect means. For example, when a detonation sensor hears "knocking", the computer will retard timing. On some systems, it will tell a solenoid to cut off vacuum to the distributor vacuum advance solenoid. Timing is retarded. On other systems, the computer may be directly involved in controlling engine timing, and it just retards the firing slightly until "knocking" stops. The method used is different, but the effect is the same.
NO RELATED
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.