Suburban died and won't restart (but sometimes it does...)

[project_x]

I was packing up to head to the cottage... And my Suburban started and died as I was reversing.

No Codes

Just cranks....

My feeling was the fuel pump...

When I go home from the cottage (it sat for 3 days), I pulled the fuse (good) and reseated it and swapped the fuel pump relay with the horn (horn still works). It started right up.

No visible fuel leaks, drove it around the driveway, start every time no issues, still no codes.

After trying around my property for a a few days, I decided to go to the lumber yard and a couple of stores close to home.

No issues, until the very last stop. (Stopped and started many times, no problems). When i tried to start it at my last stop... it would crank, run for 2 seconds and stop. No codes

Waited 30 min for a tow truck, tow truck driver starts it and drives it on to the flatbed.... and then drove it off at my house.

I try to move it to a better spot and it stops...

Yesterday, I put a fuel pressure gauge on it... says 60psi and it ran no issue for 45 min in my driveway and was able to move it no problems....


Ideas?
Crankshaft position sensor?

 

[TJ Baker]

Ideas?
Crankshaft position sensor?

NO!! Replacing a CKP requires a relearn and that requires a $$$ scantool. I would never replace a CKP unless it was conclusively proven bad.

Most likely an intermittent electrical issue.

When it fails to start, what is seen at the instrument cluster? Security light on ?

 

[mikez71]

Bad fuel pump or CKP are prime suspects for an engine dying, without codes or other symptoms.
You may have to wait for it to happen again to check the fuel pressure..

 

[project_x]

Now that I want to I can't seem to make it happen...

 

[Fless]

I would suggest monitoring the intake air temp and the ambient air temp to see if they are accurate.

Also, have you tried clear flood mode after it happens? (Hold accel pedal to the floor while cranking.)

 

[project_x]

I have not tried flood mode

 

[89Suburban]

Next time it happens smack the bottom of the fuel tank with your fist or something and see if that wakes up the pump. Then you'll know.

 

[Fless]

When it doesn't start, have someone turn the key on while you listen by the fuel tank to hear the pump running. If it doesn't, try smacking the bottom of the tank.

 

[89Suburban]

Smack that asss

 

[Fless]

Smack that asss

That's how I got mine started on the last morning of a camping trip a few years ago. Stuck in Laramie, WY, at a campground waiting for the tow truck. Wasn't sure what I would do with the camping trailer while the Hoe got fixed. But I whacked the tank a few times and it started right up. I didn't turn it off until I got home later that day, and installed a new pump a few weeks later.

 

[LsHart]

In this situation I would blame the fuel pump. The ohms are climbing and it shuts off til cool. Also, am I missing something? Don't see the "what are we working on" part.

 

[Fless]

How was the fuel pressure tested? KOEO, or running?

Year, make, model, engine?

 

[project_x]

2005 Suburban 5.3. fuel pressure was check both engine and not running with key on

How was the fuel pressure tested? KOEO, or running?

Year, make, model, engine?

 

[LsHart]

Okay, what was the readings? I guess its fixed Fless?

 

[project_x]

Okay, what was the readings? I guess its fixed Fless?

I mentioned it in my original post, 60psi

I'm not at home rn, but I haven't been able to get it to not start...

 

[LsHart]

Whats koeo? And after 5 minutes holding that pressure, does it drop?

 

[project_x]

Engine running 60psi

Koeo 60psi
It did not drop after 5

 

[LsHart]

60 on both?

 

[project_x]

Yes

 

[LsHart]

Well, if it's not acting up then that's a good thing.