My 97 F350 has 336,000 and still running pretty strong...except when hot (up to operating temp). It starts right up when it's cold and runs pretty smooth. then when it gets hot it idles really rough and almost dies when put into gear.

That's just an intro but i'm thinking after replacing the IPR orings and it helped a little and now it's doing it again that it must be my HPOP. besides, it has really lost power lately and i just feel like the injectors are not getting the pressure they need to fire correctly.

Here's my question though, if I replace my HPOP but leave the injectors, will the new HPOP cause the old injectors to fail?

 

It could be the injector oring or the injectors itself need to be rebuilt

 

I think you are on the right track with the IPR. If it starts fine and runs fine and is just having the problem when hot, thats what it sounds like to me...

To answer your question. If you replace the HPOP, it will not cause the injectors to fail. Im assuming those aren't the stock injectors? If they are, you might want to get them check out. Thats alot of miles and they might be pretty worn.

 

I honestly doubt these are the original injectors because i bought it with 280,000. it was very well maintained so i recon TPO had them replaced at some point but i don't know.

Assuming the injectors are newer than the 336,000 you're thinking there shouldn't be any problem with a new HPOP though?

Another question...will a new HPOP come with a new IPR?

 

If it is indeed a new HPOP, it should come with a new IPR. If its a rebuilt HPOP which is what i might suggest you look into, you might look into just buying a new IPR.

Give Joey @ Terminator Engineering a call. Talk to him about rebuild options. He could also sell you a new pump if thats the route you would rather take.
Terminator Engineering

 

I don't know of any new or reman HPOP that come with an IPR. They are another $250+- item.

You won't harm anything with a new pump.

And you can always pull your valve covers off and look at the top of the injectors.
Reman from Ford (Ford doesn't sell new) will be etched with an R or have a shiny steel plate on top.
New from Alliant will be yellow and first letters will be AP.
And if a PSD injector shop worked on them you most likely won't know by looking at them.

Otherwise they should be brown in color and have first to letters of AA.

 

Jim is correct. They don't come with IPR's. I'm not sure what i was thinking. Your injectors could also be AB's depending if its a cali truck or 49 state truck.

 

I's start by seeing if anyone nearby has a scanner that can monitor ICP for you before you just start throwing parts at it. A weak HPOP will usually show signs of trouble when under heavy load, not at idle.

When the idle gets rough, have you tried unplugging the ICP sensor to see if it smooths out any? If you want to replace something, try a new IPR first.

 

I haven't tried unplugging the icp. Thanks for the tip on inspecting my injectors. I will try the icp trick tomorrow.

 

Ok. Unplugged the ICP after it reached operating temp. It stumbled a bit then after the computer realized it was not connected it recovered and ran the same as it did before. Just seems like it's missing but only when it's hot.

Do I need a new ICP or should I try a new IPR? Just trying to avoid paying the diagnosis charge if possible. I forgot to mention that about 6m ago I replaced the IPR o-rings and it seemed to help for a few months. Now its even worse than before. Could the IPR be bad now?

 

If it was missing and you unplugged the ICP and it continued to miss, then your ICP is fine. If new o-rings on the IPR seemed to help for a while, I'd buy a new IPR before I spent money on an HPOP. Cleaning and re-sealing the IPR isn't always 100% effective.

 

my dad has the 2003 7.3L engine. If i wanted to take his IPR out and put it in my truck, would it work? Is it the same part #? This would be a good way to test no?

 

Yes his IPR will work fine in your truck, but I'd plan on putting new o-rings on it to play it safe. Always a good idea when removing and re-installing things to put new o-rings on there.

 

Well guys I went ahead and bought a new IPR on ebay for $99 + shipping. I put it on last weekend and i think that did the trick! My truck runs much smoother now even when it's cold and it was REALLY COLD last week here in Lubbock! we hit a low of 1° which really doesn't happen very often.

The truck did great and now when it gets up to operating temp it just keeps on ticking like it should. Oh, i also did the FPR shim finally. That made a big difference too! i don't know why i waited so long to do that one because it was SOOOO easy!

Thank you guys for your wisdom and advise! You have saved me so much money in the past few years! I LOVE THIS FORUM!!

 

Awesome to hear man! Glad the truck is running good.