Will not start after replacing freeze plug?

Hi Bobby, if you prime the engine with fuel and it does nothing, either you have no spark at the plugs, very low engine compression, or a timing issue.

Here is what I need you to do. Try using starting fluid to see if it starts. If it does and then stalls, we know there is a fuel-related issue. If there is absolutely no change, check for spark to the plugs.

Here is a link showing how that is done:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

Now, if you do have a good hot blue snapping spark at the plugs and the starting fluid makes no difference, we have a compression issue or a timing issue. However, that isn't something that would have been affected by replacing a freeze plug, so my money is on either no fuel injector pulse or no spark.

Let me know.

Joe

Bobby,

Were you able to confirm there is no spark to the plugs? Also, just for confirmation, you indicated this is a V6. Is it the 4.3L V6 and is it a full-size truck or an S10?

If you confirmed no spark, my first suspect is going to be the crankshaft position sensor. I don't want to suggest it without confirmation. Also, if you have a scan tool that provides live data, check to see if there is an RPM signal when cranking the engine.

Let me know.

Joe

Hi,

To check the sensor, you can do it one of two ways. If you have a tachometer in the vehicle, see if it moves while cranking the engine. If there isn't one, you need a live data scan tool to check for an RPM signal.

Let me know.

Joe

Hi,

The crankshaft position sensor is located behind the crankshaft flywheel. It is held in with one bolt.

If you look below, I provided the directions for the removal and replacement of the sensor so you can see its location and how to replace it if you choose.

In the pic, it appears that the harmonic balancer/crank pulley will need to be removed, but it shouldn't.

Let me know if this helps.

Take care,

Joe

See pics below.

Hi,

The freeze plug in and of itself won't prevent spark to the plugs. I have a feeling when the freeze plug was replaced, a power supply or wiring was damaged.

Let's try this a different way. I attached two pics below. Pic 1 provides the power supply to the coil and ignition control module (ICM).

In pic 1, you will see the ECM 1 fuse in the under-hood fuse box. Take notice of how many things get power from the fuse via a pink wire. First, confirm the fuse is good and there is power to and from it. Also, note there are several splices in this circuit as well.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

If that checks good, go to the ICM and the ignition coil and confirm the pink wire to both has power when the key is in the on position.

Also, confirm the black wire from the ICM provides continuity to ground.

One other thing. Remove the distributor cap and have a helper crank the engine to confirm the distributor is turning.

Let me know what you find.

Joe

See pics below.

Hi,

It sounds like you are referring to the hall effect switch. That is basically a pick-up coil that provides cylinder information to the vehicle control module.

What color are the wires? Could you take a pic and upload it for me to see?

Let me know.

Joe

Did you check the ECM 1 fuse in the under-hood fuse box? Also, is there power to and from the fuse? Check that first and let me know what you find.

As far as powering them separately, it won't work. That fuse powers multiple things.

Let me know.

Joe

See pic below.

Hi,

If you run power to the pink wire, you would need to get it at the splice where they all connect. Otherwise, you will only power one.

If you want to determine if the injector is the issue, see if it starts using starting fluid. If it does, then we know it is a fuel issue. If you have fuel pressure at the rail, the only other thing is the power to the injectors.

I'm not sure what you meant by this. Could you explain? " Control mod is hot only the coil is ly from thenot hot everthing eles seems to work"

Let me know.

Joe

Hi,

What code are you getting? Also, why were the wires too short? Were they pulled? What color were the wires you repaired?

Let me know.

Joe