Where can you find the EST wire on a 92 Chevy Blazer S10 4.3 Vortec?

There isn't a single wire specifically called an "EST wire" on a 1992 Chevy Blazer S10 with the 4.3 Vortec engine. The 4.3 Vortec uses an Electronic Spark Timing (EST) system, but it's controlled by a module and several wires rather than one dedicated "EST wire."

To find the relevant wiring, you need to look at the engine control module (ECM) and its connections. The EST signal is sent from the ECM to the distributor. You'll need a wiring diagram specific to your 1992 Chevy Blazer S10 4.3 Vortec to identify the correct wire(s). These diagrams can be found in:

* A factory service manual: This is the most reliable source.

* Online automotive repair databases: Sites like AllDataDIY or Chilton offer wiring diagrams (often subscription-based).

* Haynes repair manual: Less detailed than factory manuals, but still potentially helpful.

Instead of searching for a mythical "EST wire," focus on finding the wire(s) that connect the ECM to the distributor. These wires will carry the signal controlling the spark timing. Look for wires coming from the ECM connector that are labeled (or can be traced with the wiring diagram) as related to the distributor or ignition system. They might be labeled something like "Ignition Control," "Distributor," or have a specific pin number referencing the ECM connector.

Without a wiring diagram, visually identifying the correct wire is extremely difficult and risky. Incorrectly tampering with wiring can cause further damage to your vehicle. Using a wiring diagram is absolutely essential for any electrical work on your vehicle.