2004 SUBURBAN RANDOMLY DIED; NEW FUEL PUMP

[W8MCC]

Started acting up two days ago.  It died on me for the first time.

 

I instantly thought fuel pump because it started back up and then died.  Then I pounded on the gas tank and it ran for a few minutes.

 

I put a new fuel pump in it that night and thought all was well.

 

Then yesterday it died again on me, but started back up.

 

Today it died on me twice within a minute and I didnt make it 1 mile from the garage.

 

I have changed the fuel pump, and swapped the fuel pump relay with another.  Beyond this IDK where to start.

 

I have a snapon scan tool and its logging right now hoping to catch something if it dies again.  Thing is it seems completely random, not related to hot or cold.

 

What can I check?

 

 

[CamGTP]

Could be spark related now. Like a bad crank sensor or something along those lines.

[W8MCC]

Ok.

 

This morning it died on me again at 60mph on rhe highway.  It bucked once and then just died.  I slipped it into neutral and had it restarted before I slowed down to even 50mph.

 

It's like someone shuts the key off, just bam...dead.

 

I did notice the other day when it died sitting still that the fuel pump came back on like 1 second after it died.  This is what led me to think field pump relay.  Now I'm no sure though.

 

What parameters should I monitor while driving?  If you loose a crank sensor would the truck die, or just run like crap?

 

I'm stuck here...

 

 

[W8MCC]

Also... there are no codes, nor history codes...

[It's Tim]

Connector @ the pump or ground is toast.

[W8MCC]

I didn't notice anything with the connector when putting the pump in.

 

Which ground do I check?

 

 

[W8MCC]

Turned out to be a bad crank sensor.  Easy to replace and hasn't died on me in two months.

[richard wysong]

When the crank sensor was going on my 98 it would shut down momentarily on the highway and did throw a code for it. Upon removal you could see where it had been rubbing the crank, the new sensor came with a shim to fix that. Before that I had to have it towed in to the shop as it just died on me 1 day, After 2 days of diagnosing I found the wire to the crank sensor had grounded out on the exhaust manifold, no codes