[tminter]

on my 89 4.0 after serious mudding will not start I've changed plugs the crank sensor, coil, got fuel will the NSS allow engine to turn over but not crank? or do I need to look else where?

[xjfever]

The NSS will not let the engine turn over. Have you tested fuel pressure, and spark?

[tjwalker]

xjfever is right; you have to determine what you're missing.

Try spraying some starting fluid into the intake. If it starts and runs momentarily, then you have a fuel delivery problem.

For spark, pull a spark plug and keep it attached to the plug wire. Place the plug electrode near a good engine ground. Have a buddy crank the engine while you watch. You're looking for a strong, blue, snapping spark. Orange/yellow is a weak spark which isn't good.

Once you know what you're missing, the suspect list gets a whole lot shorter. Post back what you find!

[dz1087]

I recently had to replace the camshaft position sensor on mine, but it threw a code a few days before completely dying. Had spark, and fuel pressure, but the injectors weren't firing.

I'm still not sure if the aftermarket crank sensor I put on recently the cam sensor or not, but they went out within three weeks of each other. It still takes a long crank to get it going when cold now.

[tminter]

fuel isn't the issue i think it is the spark the color was orange/yellow real strong though the spark increased when i changed the coil what causes the spark to be yellow?

[tminter]

hey guys also I've tried pulling codes on my 89 by turning key off/on I've tried several methods I can't get the check engine light to come on since i can't get it out of my yard what now I could use all of the help

[xjfever]

You don't have a CEL on the 89. I would change the plug wires, and the distributor cap.