P2291 fault code in continuous memory
 

2005 6.0 power stroke, E-350. Runs good, starts cold good, but when hot it is hard to start. ICP sensor tested good. IPR % going too high. Any help? Thanks.

I read this post on another forum (from a Tech):

90% chance the STC fitting leak, 9% chance a high pressure oil rail port plug o-ring leaking, 1% chance of something weird. Every 05-07 6.0L will need the STC fitting replaced at one point during the life of the engine.

ok lets try this.
what is the ipr reading with the engine running at idle and eot above 185*
what is the icp pressure doing when its hard to start.

What I Got From The Tech
 

Here is what the tech gave to me: IDS test P2291 ICP to low engine cranking in continuous memory. Test drove and got engine to operating temp and monitored the IPR% and the ICP pressure during engine starting, found IPR % going too high.

The IPR % should be 20 - 30% during engine cranking. When at operation temp the IPR % was goiung to 80%. Possible causes are high pressure pump, ICP sensor {checked OK}, IPR valve or leak in the injection control pressure system. Most likely there is a leak in the ICP system.

Recommends: Removing both valve covers and high pressure pump cover and performing air pressure test on IPR valve and if IPR valve is ok, air pressure test ICP system to find leak. Must retest after any repair.

I am new to diesels, great with gas powered stuff. Is this something for the pros, or could I fix it?

sorry but durring engine cranking the ipr should be at 84%. not 20-30.

So, am I good with the 80%? What else do you make of the techs findings? I appreciate the help, thanks

if the ipr was at 80% wile at hot idle then you have high pressure oil leak, failed pump ora bad ipr valve.
just so you know ipr should be around 22-24% hot idle up to 30% but imo thtas to high.
ipr sould be 84% when cranking.

How would you go about repairing this?

that is covered in the tech folder. There is a good discription of air testing the system.

So is what the tech said the correct way to test my system? Is the tech folder on this site? The tech said it would take about 8 hours to get to the IPR valve? Is there a view of the 6.0 power stroke that will show me where the parts are? Sorry for all the questions!

I dont know whatthe tech told you as far as how to do it.
the ipr valve takes about 30 min to get to if you know what you are doing and have the tools.
for what its woth you can have the heads off in less time then 8 hours.

I hate to keep pestering you, you've been alot of help, thanks. I have a van, E-350, does that make the level of difficulty more? The tech said it would take about 7 hours to get both valve covers off. If the IPR valve test bad, do you go further and do a air test?

getting the valve covers off a van is a nightmare. not a job I like doing. to remove the ipr on a van is not bad its in the same spot as on a truck engine but can be removed by taking the engine cover off.

If I test the IPR and its bad, do I go any further or should I consider it fixed? Doubt I'd be that lucky.

well put the ipr in it and try it. if that does not work then go from there. I will say working on a van is no joy, no walk in the park. if you have any doubt then you may wish to take it to a shop.