long cranke time

[mrziggy]

About a week ago my 05 f350 started to take 2-3 times more cranking time. Its not cold anymore. lows in the 50s. If it sits for 6 or more hours, it crankes quick for twice the normal time, than fires rite up. No check engin or anything. Just changed the fuel filters but that didn't help.

Thoughts?

 

[airdrew99]

My guess would be the Glow Plug Relay (GPR). Check the voltage drop across the two heavy terminals when the key is turned to the on position. They should not be more than 0.1V or 0.2V different. Also, check the resistance of each glow plug at the valve cover plugs. I believe they should be less than 2 ohms.

Drew

 

[RoyBoy]

6.0L doesn't have the same GPR as a 7.3L. The 6.0 rarely has glow plug problems. Sounds like a HPO leak possibly the STC fitting. You would need a scanner capable of live data to monitor the HPOP pressure on hot startup.

 

[mrziggy]

will running it this way damage anything? Gota long trip planned this weekend, but don't want to trash anything.

I will try getting it scanned today

 

[djanzen]

the 6.0 has a glow plug module and i have replaced one in my truck. if there is something wrong with it a scanner will show it

 

[mrziggy]

new development

Ran it hard pulling the trailer this weekend, now the problem is gone. Could it have been EGR related?

 

[claigaie]

long crank time

Have you changed the oil recently? The non oem oil filter can cause probelms.

 

[2 Stroker]

Ran it hard pulling the trailer this weekend, now the problem is gone. Could it have been EGR related?

One thing to remember with the 6L, once a week you need to drive it like you stole it to help keep the egr valve and turbo clean and use cetane boost in the fuel. YouTube - ‪Motorcraft Cetane Boost Video 6.0 & 6.4 Power Stroke EGR Related‬‏
and use only Ford filters
YouTube - ‪Motorcraft Power Stroke Diesel Filter Comparison‬‏
and weak or bad batteries will kill the FICM that will give you hard and ruff starts when cold i keep mine on a Battery Tender Plus when it sets
YouTube - ‪Ford 6.0 FICM Testing & Removal Instructional Video‬‏
Hope this helps
2 stroker