2005 gmc safari wont start checked coil spark

The first thing a mechanic would check is for power and a ground signal for the coil. The pickup coil in the distributor sends a signal to ground the coil. The coil sends the spark to the distributor cap thru the rotor to the plug wires.

sounds like a bad ignition module check for spark when it dies if you do not have spark at plugs check between coil and coil wire if still no spark most likely module it is under rear of distributer cap resembles a black wafer board with two electrical plugs

It is the Ignition. If you put starting fluid in it, and it did not start, then you probably have no spark.

Check that you have spark to the spark plugs. If not, then check the vehicles' Ignition System, and repair as neccessary.

buy a can of starting fluid, spray into intake hose, see if engine starts, possible fuel pump prob.

Sounds like it is either a bad coil pack, cam position sensor or crank position sensor. The coil pack delivers the spark to the plugs and the 2 sensors tell the computer when to tell the coil pack to spark.

bad spark plug or wire mabe a bad coil

Check the starter relay.

For distributor/ coil ignition; Check the following;
1 Check if you have the spark at the plugs. Broken
plugs do not produce sparks at the center contacts
Replace as needed.
2 Check your ignition coils if this is still O.K. The coil
supplies the spark plug thru the distributor, to make
the spark, and make the engine run.
Assuming all the defects are already connected, restart your engine, and send in your e-mail.

I had the same problem with my 2000 GMC Safari two years ago....drove me CRAZY!

Sometimes it would start right up...other times it just would crank and not start.

It turned out to be a cracked coil....I found it by using a spray bottle with water in it, and "misting" the engine, at night....with the engine running. (On a night when it DID start!)

It took a while, but finally the hairline crack let in some water and the electrical short showed by a spark coming out of the coil.

I replaced the coil with a new one, and it has never "not started" since.

Evidently the coil cover gets brittle and develops small, hairline cracks due to heat from the engine.

Oh...by the way....I tested the coil it showed that it was fine!....but it took the "misting" at night...in the dark...to find the spark "leaking" out.

I'd replace the wire set.