Starting Problem with my 1997 GMC Jimmy?

[the wisdom bank]

When I attempt to start my 1997 GMC Jimmy, it makes a loud grinding noise. It sometimes wants to start but will not. It is not the starter, or the flywheel. What could it be?

 

[Molson02536]

When I attempt to start my 1997 GMC Jimmy, it makes a loud grinding noise. It sometimes wants to start but will not. It is not the starter, or the flywheel. What could it be?

Common for the serpentine tension idler arm to fail which can cause the issue you have described. The other would be a failed alternator bearing and the windings are rubbing against the armature making your alternator pulley to seize.

Remove your serpentine belt and inspect the tension idler arm and make sure that there is no signs of damage or miss alignment, the alternator should also me inspected and turn the pulley by hand and look and feel for any binding or grinding noise like your have mentioned.

The other things would as mentioned earlier and or the timing chain has failed. Good luck and keep us posted.