<Reposted from another thread to avoid confusion in responses>

I have a 98 Blazer and I was driving the highway to work and effectively I lost electrical for a moment shutting the engine off at 60mph. Thankfully I was able to pull over safely. The vehicle immediately started back up once I should get it in park and turn the ignition.Continued the drive and the engine "staggered" (kind of lurched as the engine kicked back in) a few times but didn't fully shut off. Battery warning light flashed on in those times. It's currently sitting in the parking lot and I'm hoping it starts for me to get home.

(By "losing electrical" I mean the battery light flashed on and flickered. I don't know if other electrical went out as it was daylight so I didn't have the lights on nor did I have the radio on.)

 

I'll bring my response over as well.

A flashing battery light just means that the charging voltage went below the level deemed adequate to charge the battery, usually a voltage in the 13.X's. A stumbling engine can cause this as can the actual loss of charging from a running engine. You will still have adequate voltage to run the truck until the depleting battery voltage drops low enough for the ECM and/or ICM to quit working, usually around 10.XV. If other electrical components were cutting out like dash gauges, interior lights, radio, headlights, etc then that would be a more global loss of electrical power and may mean that you have lost ignition voltage even with proper battery voltage.

This could be fuel pressure, ignition or fuel injection.

When it won’t run/start you should measure your fuel pressure after key on and if it will crank do you have spark? Those first two are pretty easy to check, fuel injection is more involved but also the least likely.

Also, measure your resting battery voltage and voltage during cranking.


George

 

Thanks for your response and letting me know to create a new thread.

Well, after the rest of the afternoon I am definitely going to have to run with your idea of the fuel pressure / fuel injection. The vehicle did the same thing on the drive home tonight, however when it stopped it decided it was done. Lights still come on, ignition still goes, engine continues to turn over... However it just refuses to start. I had it towed back, so I guess I will look at the fuel pump first and then go from there. (?)

 

Towing sucks but a hard failure is much easier to diagnose and fix.

You check for spark at a couple of spark plug wires. Look for 1" of strong blue spark with a regular cadence while cranking.

Test for fuel pressure and leakdown using the sticky at the top of the gen 2 thread..

If you get that far with no joy then its on to fuel injectors which uses a noid light or test probe.

Here is some lite reading:

https://blazerforum.com/forum/2nd-ge...rticle-103750/


George