Diesel mechanics, got a question for you

[88GT]

2007 6.0L Powerstroke

It has recently started taking longer to crank over and start. But only on cold starts. Not ambient air temp cold, but engine cold. After driving it for about 20 minutes, it will start right back up no problem for as long as the engine remains up at operating temp. The only hard, long crank is the initial one.

Originally thought it was the FICM. Replaced that, but the problem still exists. Possibly the injectors, but there are no other signs of injector problems though: no white smoke belching, and no other long starts. Could also be the glow plugs, but I would think those would also result in long starts at every start, not just the initial one. Alternator? Low batt voltage on start that is remedied during drive?

I have a CTS monitor that provides OBDII info. Batt voltage is a smidge low on start-up, but not a lot. Of course, I don't know what's a threshold level for batt voltage either. FICM is a rock steady 48.0/48.5.

There are no codes.

What else could it be?


I don't know if this is relevant or just a coincidence. The CTS monitor used to power up when the ignition was turned to the on position. Now it won't power up unless the engine is running. Another batt volt issue?

I'm about to tear down the Expedition to replace head gaskets so I don't want my only remaining family vehicle to crap out. I'd really like to have this solved, if not resolved, before the Expedition is out of commission.

 

[ggglobert9]

Glow plugs

 

[Scarecrow]

Was having the same problem. Replaced both batteries and have been fine ever since. I should also say, that was after replacing the alternator twice. Darn Chinese products.

 

[Mosinguy]

Check the charging system. Also how old are your batteries? Get Autozone (or equivalent) to test your alternator. I'd guess you'd find your problem lying in those areas.

 

[88GT]

Was having the same problem. Replaced both batteries and have been fine ever since. I should also say, that was after replacing the alternator twice. Darn Chinese products.

Did you replace the alternator because you thought it was the problem or just as an attempt to diagnose it? Curious more than anything.

How old were your batteries?

Mine are just over a year old. I don't think they should be crapping out on me yet, but who knows. We'll try swapping batteries first. It's the easiest fix at any rate. Thanks.

 

[giovani]

Sounds like glow plugs, or the glow plugs are not being powered up.

 

[CTC B4Z]

in the years Ive been messing with the 6.0, I have literally only replaced a handful of glowplugs... More commonly the GPCM, glo plug control module, but you would be belching out white after it finally started...

But I assume you have no codes for it...

Batteries are must in great condition for the 6.0. Bad batteries kill FICMs also. Also jump starting does too..

PM your location.

 

[Scarecrow]

Did you replace the alternator because you thought it was the problem or just as an attempt to diagnose it? Curious more than anything.

How old were your batteries?

Mine are just over a year old. I don't think they should be crapping out on me yet, but who knows. We'll try swapping batteries first. It's the easiest fix at any rate. Thanks.

2005 f250 6.0
I replaced the alternator after autozone tested it and it was bad. I think that is what wore down the batteries. BTW, the batteries tested within limits, but a mechanic friend told me these engines require a silly amount of pressure in the system to start properly. So I replaced the batteries and bingo, starts up fine again. I am no mechanic, this is just what worked for me.

 

[CTC B4Z]

how many miles? how long is exactly a long crank? when it first fires up, is there any shaking or misfiring?

Im thinking you may have an HPO system leak down... but when engine is screaming hot, does it start fine?

 

[CTC B4Z]

Meh, these trucks take a pretty standard set of batteries, nothing extreme. You have to figure you have glow plugs cycling, FICM sucking down voltage, along with everything else. For that initial start it needs alot of juice...

 

[88GT]

in the years Ive been messing with the 6.0, I have literally only replaced a handful of glowplugs... More commonly the GPCM, glo plug control module, but you would be belching out white after it finally started...

But I assume you have no codes for it...

Correct. No codes for anything. And no belching of any colored smoke (except when I haul ass on a hard throttle to pass someone )

Batteries are must in great condition for the 6.0. Bad batteries kill FICMs also. Also jump starting does too..

PM your location.

Batteries are only about a year old, replaced them in January 2012, IIRC. Haven't needed to jump start it.

Location is SW Indy/Camby area.

 

[ws98ta]

I would agree with ctc.
Seems like your high pressure oil system is leaking down while sitting for a while.
If you obd II readout shows icp check that on cold starts and see how long it takes to build to 500psi.

 

[jrainw]

Check the glow plug relay, I haven't replaced any glow plugs in 6.0s yet but the relays do fail.

 

[CTC B4Z]

but if CTS isnt powering up til after system its charging, its too late...

you should be able to flip a switch on your CTS to convert to constant power, either on the OBD plug itself of the monitor... I know for a fact CTS will read ICP... You want to see a damn near immediate spike to 500....

this could be an early sign of a HPO leak... usually these leaks when bad will cause a no start hot... but I have seen some drain back over night...

basically your injectors are fired off @ 500 psi of OIL pressure, than the system can reach 4200 PSI to run these injectors... There are countless seals and joints these systems leak at...

Charge up the batteries, cycle key, and watch ICP while cranking... get back to me

 

[sepe]

Did you replace the alternator because you thought it was the problem or just as an attempt to diagnose it? Curious more than anything.

How old were your batteries?

Mine are just over a year old. I don't think they should be crapping out on me yet, but who knows. We'll try swapping batteries first. It's the easiest fix at any rate. Thanks.

What are your batteries reading?

Have you checked the ipc (injection pressure control)? I've heard of no codes, pretty rare though, with that being the culprit.

 

[CTC B4Z]

there is no relay.. like I said prior, its a GPCM, but since no smoke, I doubt its the issue.. Very easy to throw a code when its bad too since it emissions control

 

[88GT]

how many miles? how long is exactly a long crank? when it first fires up, is there any shaking or misfiring?

Im thinking you may have an HPO system leak down... but when engine is screaming hot, does it start fine?

107K

3 or 4 seconds longer than typical.

No shaking or misfiring.

MR88GT also put HPO on the list of possibilities. Here's what he has to say:

Here are some more of the specs from the CTS.

Engine Off Key on.
ICP voltage is 0.3V or so.
Battery voltage is 11.6-11.8 (this makes me think it may be the batteries)


Crank engine for 5-10 seconds (it's not really 10 seconds, just seems like it).
ICP voltage 0.9 to 1.0V
ICP voltage comes up from 0.3 to 1.0V over the time to crank and start. Goes up to about 1.4 at 1500 rpm(this makes me think it may be the ICP sensor, or I have an HPOP oil leak since it takes so long to get to 1v and 500 PSI)
ICP pressure is around 650 on idle. A little more right after start, starts around 750 and drops to 650ish. Goes up to about 1000-1100 at 1500 RPM.
Battery voltage goes to 12.8-12.9 when running (again making me think batteries)

Truck seems to run fine once started. And has a normal crank once warmed up.

Batteries are 1 year old Deka's, but I will probably start there. ICP sensor will likely be next. (where can I find this bad boy?) If it's HPOP I will just rip the top end off, and install the BPD oil cooler and EGR cooler kit, stud it, update all the stand pipes, dummy plugs, bango bolts, and hopefully fix it for good.

 

[CTC B4Z]

ICP sensor is not at fault, but its on pass side valve cover. Whats your IPR duty cycle when engine oil temp is op temp(180°-200°)

voltage is as issue here, but I dont think its the full factor... no reason charging the batteries shouldnt be at 13.5..

and you dont wantt he BPD oil cooler... freaking WASTE of money... Just toss a coolant filter on now, and flush it out when you do change the cooler...

 

[SSGSAD]

With the engine off, the batt. Volttage, should be around 12.0-13.2. Not saying they are bad, but if you can, charge them for at least a couple hours, and then test. Drive, and then let set over nite, and test batt., again. See what the Voltage is then. If it drops, then the batt., are not HOLDING charge....

 

[88GT]

ICP sensor is not at fault, but its on pass side valve cover. Whats your IPR duty cycle when engine oil temp is op temp(180°-200°)

voltage is as issue here, but I dont think its the full factor... no reason charging the batteries shouldnt be at 13.5..

and you dont wantt he BPD oil cooler... freaking WASTE of money... Just toss a coolant filter on now, and flush it out when you do change the cooler...

What's the IPR?