Hi all,

2002 Excursion. Was cleaning up the engine compartment because of oil, power steering and coolant leaks that made a mess on Tuesday night. Truck was running fine. Used engine degreaser liberally and then sprayed down the engine with the hose - being careful around the electrical. Done this several times with no issue. (haha - I know).
Fired it up when I was done and it ran fine for a minute so I shut it down and went to bed. Fired up Wednesday morning - all good. Drove 30 min to work. No problems (except slight coolant leak at cap -grrr).
Go to leave work and turn the key - did not hold it on long enough and it stumbles and acted funny - bucked and shuddered. Shut it down, waited 10 seconds and tried again - figured I did not crank it enough first time. Fired up and all seemed good. Idle was a little higher than normal, engine sounded different. Hmmm....drove ok while going to a buddy's house. Pulled up to his house and thought I should plug in the AE and check things. While setting up the laptop, idle becomes real rough and sputtering. Plug in and see a bunch of codes:



Well - I figured maybe some water got in the sensor - damn. Unplug it - no change. Get some electronics cleaner and spray both ends - same result.
Leave the vehicle and go help my buddy on his KOH race truck we are working on. Come back in an hour, fire it up and drive it around the block and it appears fine. Pull in front of his house and let it idle - starts doing it again - rough idle, shuddering when giving gas. Damn.
Leave it again, come back hour later - drag the air hose to the truck - blow out both sides of the sensor - also the IPR sensor to be sure.
Appears ok at idle and revving. Sweet. Go back to garage - by now it is 11PM and I finally go to leave at 12AM. Start to pull away and it dies - crap. Start it up and drives ok - not great - for about 3 blocks - I pull up to a stop sign and the idle is crap - barely staying running, shuddering, etc.
Keep going and does this for about 3-4 miles. I keep it around 40-50 and it ran ok but every time I came to a light it shuddered, idled rough and wanted to die.
Another 2 miles and started running better. Soon was back to normal.
So I open the laptop, start the program, connect and retrieve all data - I start losing almost all power and shuddering comes back - crap! I shut the laptop and within 3 seconds back to almost normal. What gives?
Was I in default mode because of a bad ICP and when AE tried reading the sensor it sent it haywire? Did not want to try it again since it was almost 1AM and I just wanted to get home and not have to call the wife to come get me somewhere.
So I am thinking I messed up the ICP or the pigtail wires when cleaning - either water or moving/bending the wires around created an electrical break. Any other thoughts?
I do have a slight leak at the HPOP gasket, not bad though, and it is a 1ish year old T500 I installed. I also the Riff Raff fuel crossover and oil crossover. Oh - and I did clear the codes and the MIL is still on and I am down to only the P1280.
Open to ideas, thoughts and questions!

 

Did you do a KOEO? I learned this can clear the PCM's throat when it's choking on a bone (data error).

Were you using an OBDII scan gauge like Torque or Dash Command for daily driving?

Did you try driving with the ICP unplugged?

Did you look at your ICP/IPR/FIPW/RPM while driving?

What is your battery voltage while idling?

 

Unfortunately I did not have much time last night - the purpose was to help a friend, not work on my stuff.

 

ok cleaned the pigtail real good. Idling ok. Here is a screenshot of values:




Values look ok?

 

and now she seems to be running ok again. Here is another snapshot after a little warmer:




Thinking I got some water in the connector. Used electronic parts cleaner and a little compressed air (from a can) to clean it. not getting CEL anymore. I guess I should watch it and see how she does....

 

Those numbers all look good. In the first one, the ICP was a little high for idle, but I figured it wasn't up to operating temperature. I think you are right about the water in the connector. I would check the 42pin as well. Clean it up really well with electronic parts cleaner. Get the engine good and hot, take it for a couple of hour ride.

 

Thanks. Good call on that connector as well. Drove it the 30 minutes to work and "knock on wood" all good.

 

Sorry... not 100% sold on good yet. IPR is a little high for that ICP and RPM. Spec says 9% to 11% IPR, and considering the range - you're about 7% above max. If you have single-shots, 10% is too high at 475-500 PSI ICP. Not being at full engine temp may play a role here, I'm not sure. How does it look at full temp? What does the ICP say with KOEO?

KOEO test is not temperature dependent.

All of this assumes stock program.

 

Ok - so how am I testing it? It has been in the parking lot since 10:30AM EST at 29 degrees out - pretty sure it is cold. Injectors are stock. I can run out there now.....
I do have a DP Tuner - so should I set it to "stock" mode?

 

No rush. Just something to look at if it happens again. Stock tune is always better for looking at sensors, and pulling the chip is best for troubleshooting.

 

now I am scratching my head. I went to this page:
Riffraff Diesel 7.3L ICP/IPR AutoEnginuity Set-up | Ford Diesel Performance Parts Blog

and looking at this screenshot compared to mine:


I see the following:
Riff Raff value / My value

Engine RPM: 681.5 / 678
ICP PSI : 480.80 / 474.01
ICP Volts : 0.88 / 0.76
ICP DC : 11.72 / 11.72
Engine Oil Temp: 122.45 / 149.90

Seems pretty close to me - or am I way off here? - and I am no means an expert! Learning here!

 

Well crap......spoke to soon. Went out to the parking lot and not so good. CEL is on again.
This is my KOEO results:



Got the error code again:



Here is just after startup:



Here is at 2000rpm:


Cleared the codes and got this:



Here is the KOEO Test results:




I did notice that 724.03 was constant and did not change unless i blipped the gas. I assume I was in default/bypass mode. I unplugged and plugged in the sensor and nothing changed.

So I guess it is safe to assume the sensor is intermitten (worked ok this morning to work) and should be replaced? Or should I start with the pigtail? I noticed it is not a tight fit - a little loose...

 

I'm not sure what we're up against here. Every screen I've seen so far (including that linked PDF) is on a cold engine - this skews the readings. If you have an intermittent issue, this is where the logging feature really pays you back for investing in AE. You need to log your data while driving in the real world with a warmed-up truck, and this is what you want to record:

RPM max 3500
MPH max 100
MAP max 50
EBP max 55
ICP max 3500
IPR max 50
FIPW max 5
EOT max 200 (winter) 230 (summer)

*EDIT* add Battery Volts max 15

 

Ok. So I will get it up to operating temp and plug the sensor back in and start recording the above. Thanks!

 

I threw another one in there for good measure. Pardon the pun.