6.0 rough start

Belize · 03-28-2021, 07:44 PM

Have a 2006 6.0 with 150k and has been running beautifully. Recently, on cold start, she will cough and die maybe 3-4 times before finally catching and then runs smooth. Good acceleration and runs between 195-205 EOT. The FICM voltage is a solid 48.5-49 and alternator is putting out 13.2-13.6. I live in a warm climate (never below 70). I have thrown a glow plug code, but ignored because of the climate. Recently threw a EGR code even tho the engine has been Bullet proofed. Any thoughts on where to start...injectors maybe?

desertsherpa · 03-28-2021, 10:28 PM

I would watch a bunch of diesel tech ron videos, and see if you can systematically rule out easier to fix things like IPR, sensors, and other things before injectors.

There is a ford injector contribution test that can also be illuminating.

hogasm · 03-29-2021, 04:43 AM

Can you measure oil pressure when she hits and cuts off

carringb · 03-29-2021, 07:04 AM

What are you using to pull your data? Can you pull Injection Pressure (usually called ICP but sometimes IPR) and Injection Pressure Regulator (IPR Duty Cycle or IPR %).

If ICP value drops out while cranking, unplug the ICP sensor, and see if that makes a difference. If ICP value is below 500, look at the IPR cycle. If it's above 85% when ICP is low, you have an oil leak. Or possibly a bad HPOP.

Before pointing any fingers at injectors, run a cylinder contribution test while it's warm. It'll be apparent if one or more is bad. If that does't pass, you can also do an engine-off cylinder balance test, aka "relative compression" which is the same test while cranking, to rule out any mechanical issues.

Belize · 04-02-2021, 04:49 PM

Did an oil change today and now the engine will not start. It is now throwing codes P0403, P0678 and P0683. The FICM voltage is at 49 during crank, the ICP is at 280-300. Oil pressure guage registers after 10 seconds of cranking. It really sounds like an electrical problem as only one glowplug is throwing a code, but the glowplug module is throwing one also. I'm about 50 miles from a diesel mechanic. Is there any thing to trouble shoot that might get the engine started (wiggling wires, checking fuses, etc.) or will I have to flatbed the van to the mechanic?

hogasm · 04-03-2021, 04:08 AM

You need close to 500 psi. Oil pressure to start
Buddy drove his truck 200 miles yesterday, parked for lunch and then it would not start. HPOP bad.

carringb · 04-03-2021, 07:31 AM

Try starting with the ICP sensor unplugged. It's a slim chance, but sometimes that'll get you going. You can also try getting a jumpstart, and sometimes that'll turn over the motor fast enough to build enough extra pressure.

I'm still strongly suspicious of losing high-pressure oil. Either a leak in the high-pressure, or a bad HPOP. The HPOP gets damaged when the HPOP sump screen builds up debris, gets obstructed, and eventually ruptures. And that screen has nearly a 100% failure rate if you run non-OEM oil filters with the stock filter cap because too much oil bypasses.

You most likely need a tow. I'd probably try to find a mobile welder who can fab up some base-plates for a tow bar, then tow it back using an old-school A-frame tow bar. If you use a tow strap, definitely find yourself a 12-volt vacuum pump for your brake booster. It shouldn't be hard to find a universal one at a parts store, or take on off any wrecked '99-'08 Audi A4 with an auto transmission.

If you flat tow it, it's better to tow with the T-Case in Neutral.

Belize · 04-03-2021, 12:27 PM

Removed cowling and the ICP sensor is located right behind the glow plug control module.

I disconnected the plug and still no start. The FICM Sync is 1. Any other ideas or is it a tow?

carringb · 04-03-2021, 01:52 PM

Are you able to read your ICP duty cycle? Possibly called IPR% or just IPR and shown as a decimal?

If it’s ready above 35% you have a high pressure oil leak. If it’s reading above 85% the HPOP is probably toast. If it’s reading 99% the IPR solenoid is probably bad. If it’s fluctuating suddenly the IPR is probably plugged plugged with debris from a blown sumo screen. You might be able to clean it if that’s the case, but keep in mind all that trash would also be getting into the injectors so driving is not recommended even if you clean it out.

carringb · 04-03-2021, 01:53 PM

Also, if you get the oil warm, you might be able to get started. Like plug in the block heater, tape a heat pad to the oil pan, put a pan of hot coals underneath....