2006 6.0 Hot Start Problems

[grayweber24]

Truck was bulletproofed about 3,000 miles ago. Installed arps, oem head gaskets, egr delete, stc fitting, stand pipes, dummy plugs, and 8 warren 155s. Originally the truck would fire right up cold or hot no problem. Now it wont start once the oil temp gets over 170. Even when the oil is 190 it will still build about 300 psi of oil pressure. So that sounds like the typical hpo leak, but here's where it gets a little interesting. The truck is throwing a P0148, and I couldn't find a lot about this code but I did come across this thread.

05 6.0 Rolls Black smoke; DIES; No refire; Code P0148

In there he talks about how his truck won't restart until it cools down, just like this one. The only thing is this truck runs flawlessly once started, and has never missed a beat.

I went ahead and removed the ICP and applied shop air, and I thought there was a leak on the pass valve cover. So I pulled off the oil rail, reset it, made sure it was seated and torqued right, then put in a new dummy plug and stand pipe. While I was in there I pulled the stc fitting and reinstalled it too, but in the end it didn't change anything. Where should I be looking now?

[ps_lane01]

When, why did u have 300 psi hpo? Cold, hot? And when you did hpo leak test, were u controlling the ipr closed? Do you have any datalogging info? And it looks like that OP of the link had code p0606 which was a pcm failure, but you dont have that code, correct?


Sent from AutoGuide.com App

[grayweber24]

It will only build 300 psi when trying to start while hot. I don't have the ability to command the ipr closed. I tried to apply 12 volts to it, but not sure it did anything? What data logging info should I get? The only code I have is P0148.

[ps_lane01]

Because of that code, i would bring up everything to do with fuel and high pressure oil.. Make sure you have all cmp ckp ficm and pcm sync. According to 6.0 bible a failed cmp/ckp sync will default ipr to 15% dc. Make sure you have ficm sync along with correct logic pwr, vpwr, and internal injector voltage(no less than 47v). Also Check your desired fuel mass, pulse width and injection timing. The 6.0 bible along with old threads will tell you what all those reading should be at crank. And of course check all the steps in the hot no start sticky. But yea imo i think your on the right track with a hpo leak.


Sent from AutoGuide.com App