Sunday afternoon riddle: 7.3 randomly dies.

[Maverick]

I've been told by a friend of mine who is a ford diesel mechanic not to run any kind of synthetic. He says it is really bad for the injectors.

I have no idea about that. I've heard conflicting advice and I really don't know. I ran delo for a couple of years, then went to the synthetic blend on the recommendation of G&R when I had them do my turbo 3-4 years ago. It sounded good at the time.

I know the Motorcraft IPR's come ready to install. Not sure about the parts store units.

I'm thinking Motorcraft, mainly because I haven't seen any parts store units available. The ones online all look the same, wide range in price. Heading down to Sandy Ford after lunch, their CPS price seems to be as good as anyone's, I'll ask about the IPR & ICP. Maybe I'll go home and look at the ICP first.

You might also pull the plug off the back of the ICP and make sure it is clean and dry. If it is full of oil that is a sign on a failing ICP.

Rats! I was going to do that yesterday afternoon, but got sucked into programming HAM radios (which mostly means trying to make the radio talk to the laptop and vice versa).

 

[Toad]

I developed a nasty lope at start up on my 7.3. It sounded like a rowdy cam big block. Could never figure out how to duplicate the issue. Hot or cold start very intermittent. Figured it either had to be fuel or oil related. Before I did anything I switched from a full synthetic to valvoline premium blue. Going on two years without the lope. I will never run synthetic again in that truck.

 

[Maverick]

ICP: electrical connection full of oil. Wow, those are spendy. But easy to replace.

IPR: yup, it has one. Also spendy. Doesn't look too bad to replace, and I have a Costco dial shampoo pump thingy to empty the HPOP reservoir with.

Mega work responsibilities between now and Friday and with a busy weekend and the trip next week, I'll be dropping it off to G&R tomorrow. I'll chat with them about the symptoms. They've been honest with me before when I took it in thinking it was one thing ($$$) and it was something else ($).

Will pick it up and it will no longer be broke. But I will be.

 

[bryson]

ICP: electrical connection full of oil. Wow, those are spendy. But easy to replace.

Ford sells a replacement pigtail for this harness because when the connector fills with oil, it wicks up the wires and makes for bad ju-ju... When you replace the ICP (if the plug is full of oil, it needs to be replaced) be sure to replace the pigtail too. It is a real easy job, just cut off the old plug, making sure you cut enough to remove all the oil-soaked wire, and solder on and heat shrink the new harness. I had to do this on a 99 F-250 I had a couple of years ago, that had the same symptoms yours is having.

Good luck!

 

[SLC97SR5]

Glad to hear you are getting somewhere on this, it sucks to pay a shop but they have the high end PowerStoke scanners and will run the buzz tests, cylinder contribution, duty cycle, etc...

Keep us posted on the fix, good luck!

 

[Maverick]

Ron at G&R says it's totally the chip where it plugs in to the mother board. He's seen it before, and thought it was CPS. He said if it were the IPR or ICP there would be other symptoms like sluggishness before it dies or starting up crappy initially. Anyway, he's gonna run the codes, change the oil, and then I'm gonna investigate the chip/motherboard interface.

Stay tuned...

 

[sswens1]

I also have had problems with the dp tuner chip/motherboard interface on my 7.3. When I first switched to the DP it would randomly die and not start. This went on for a while until I got around to improving the connection. It only took about 30 min, wish I would have done it sooner. I had to pull out the motherboard, scuffed the connection tab with a scotchbrite pad and cleaned it with rubbing alcohol. I also put some gorilla tape over the chip and the housing to help hold it in tight and keep it from moving. No stalling symptoms whatsoever since I took the time to do that.

 

[Maverick]

I have corresponded with Jody at DPTuner during the last two weeks regarding the issue. He offered to "re-tin" it and also reprogram the tunes to deal with my high EGT's. I do have some up-pipe blow by, but he also thought my NAPA 6637 big honkin' air filter (BHAF) wasn't helping any.

I pulled out the pcm and chip on Weds before I left to check and clean the connection. Everything looked good, tape and all. It has worked great since I installed it 5 years ago. I took it apart and cleaned it anyway. I had Jody send me new instructions, and now he has you drill a hole in the black plastic case for the wire. I reinstalled it and it worked great on the trip, no running issues at all.

When I returned home yesterday, I saw that my Stage 2 cold air intake had arrived. We'll see if it works any better than the BHAF that I put in when I did the tranny, chip, and Walker BTM (big truck muffler) 5 years ago. Combined with the "zoodad" mod, it is supposed to lower EGT's by 150-200 degrees. I can hit 1250 in the stock tune.

Stay tuned...

 

[Maverick]

Update: It was the solenoid on the IPR.

In the process of figuring it out, I gathered all the sensors (ICP, IPR, etc) that it could be and waited for it to die, and then started with the easy ones. The IPR solenoid was the second thing I tried.

Installed the stage 2 intake and EGT issues are all but gone. Very few situations will get it over 1350. Tows heavy very nice now. Tows medium uphill at speeds that will get me in trouble. Satisfied.

Injectors are starting to go, saving money for the replacement.

The water pump might be weeping.