This is in the wife's Excursion that has 247k on the clock with 2k on a fresh oil and filter change. She's noticed an occasional fuel injector knock over the past several months with no reason when it happens and then goes away. I've noticed the fuel mileage has dropped way off the last 6 months or so from 21 mpg highway to 16 mpg highway. I changed the fuel filter about 5k ago and cleaned the fuel bowl really well...think I changed the small filter screen pre pump too at that time given the fuel pickup in the tank doesn't have the filter socks in it when I changed that 6 years ago.

We took a trip out of town to San Antonio which was about 200 miles or so. No issues until we left the hotel and I started hearing the fuel knock...didn't hear it while it sat idle in the parking lot for 15 minutes. Drove it to our destination and then picked up a fuel pump given it was making a noise but was replaced with a new Bosch unit in 2016 when I did the fuel sock delete pickup. Still had the fuel knock when we got back to the hotel so I changed the fuel filter. The next morning when I crank it no fuel knock, but when we reached our destination it was knocking. I decided to go ahead and make our way back and all was good until we get about 125 miles out I noticed it surging on uphill runs...not every time though...especially on the bigger ones. We hit some traffic and went over some really bad bumps on a bridge around Columbus and a couple miles from there it would not hold speed and traffic came to a stop, so I exited the feeder and pulled over. It was missing really bad and not run unless I kept it around 1,500-2,000 rpm but still had a sluggish idle with white smoke. I really though it was the UVCH so I took a tool and pushed in on the connection outside. Luckily it seemed to have most of its power back so I continued and we had to climb an incline right off which actually seemed to clear it back up. Ran it for another 50 miles and it started acting up again so pulled over and let it cool off in conjunction to messing with the connections again. It started running better and had some power back so off we go again. We run another couple of miles and it starts acting up again so I limp it to exit and it dies going into the parking lot. It would barely crank and run so I let it cool. After awhile it starts to run better so here we go again. Make our way to a Buc-ee's to get some fuel and as we approached I can hear the knock and low power going up the overpass. I leave it running while fueling and it seemed okay but only dropped about 16 gallons into the tank. By this time it is late afternoon and we made it the last 50 miles or so home but I had to take the feeder and keep it around 45-55 mph out of overdrive to keep the rpms up...I did put it in overdrive on occasion and could get the lack of power after some time so it would come back out. At stop lights...I must have hit 99% of them!...I had to switch it into neutral and keep the rpms up 1,500 or so, then let off and drop it in drive to continue. I noticed it did run better the closer we got home.

This morning I crank it up, back it out of the garage, and it is running fine. I hook up Forscan and check codes to find P0733 (gear 3 incorrect ratio), P1670 (Electronic feedback not detected), P1247 (Turbo boost pressure low), and P3040 (Cam position sensor). There were 2 additional codes but they have to do with the glow plugs and not related. I cleared the codes and decided to run a couple tests. I ran a buzz test and all seemed good as they all sounded close in sound and the tachometer did also move during the test which tells me the IDM is fine. I also ran the cylinder contribution test and get the #3 and #8 issue code. I realize this very likely could be related to the P0340 CPS code. Non of the codes came back when I checked after the other tests but it just sat in the driveway at idle for that and not driven down the road. Both our trucks had the CPS replaced during the recall back in 2008 with the gray unit, and that's been just shy of 100k for the Excursion.

I am convinced it is in fact the CPS unless someone has something else to look at. I did look at some reading while running messing with Forscan and the ICP seemed to be around 560 or so psi cold. I've done some reading on the original black, next purple, then gray (Ford replacement) CPS units and have located a gray unit. So which CPS is the go to now? I may swap in the CPS from my truck and see what happens before I get one. I have several used spare black units I can't seem to locate that are also good when I pulled them, but I this is the wife's buggy and what we take on road trips, so I am thinking a new one is in order...

 

Purple is the go-to now. If you happened to have the intermittent wipers on every time it acted up, I would be convinced that is the problem. Since you have Forscan, it would be a good idea to do some data logging and see what the HPO is doing.

 

UPDATE:

I found a purple CPS and installed it. Fired the truck up cold and it seemed to idle smoother and was a little quieter so I took it for a spin around the neighborhood. I came back and replaced a tail light that was out. Then I decided to drive it a couple miles to the car wash and get it cleaned up from the bugs on the out of town trip we took, then came back and got it dried off and shined up. After that, I decided to drive it another couple of miles to the fuel station and get it topped off and while dropping fuel I noticed a faint knocking. Once full and on the road home I noticed the knocking getting louder and when I pulled up to a stop light it studdered and the idle was down so I popped it in neutral and kept it around 1,500k while stopped, then lowered it and put in drive to continue. When I got back home in the driveway the knocking was back. I went ahead and checked for codes and there were none, so I decided to run the cylinder contribution test and it came back with #8. Side note, I checked my F350 this morning and it also had the #8 on the cylinder contribution test. I also ran a buzz test on it since the knocking came back and all still good...tach moves a tad over 2k on each injector and all sounded about the same. When I did the buzz test this morning on my F350 it showed just shy of 2k on the tach though it was cold. I would think if there was an issue with the valve cover harness the buzz test would reflect that.

I also pulled the plug on the ICP to check for oil and there was none. This is a fairly new ICP that I replaced when I also did so on my F350 given there was oil in it, but still good. I left it unplugged and tried to start it so it go to default and see what happens. It would not fire up after several attempts, so I plugged it back in and it fired up. While setting there I let it run with Forscan to check some things and everything seemed fine...see attached.

I was leaning towards the valve cover connections prior to the buzz test as I've never had the valve covers off either of these trucks...

 

Your ICP and IPR look normal for idling. Something is wrong on the MAP side. It should read around atmospheric (14.5-ish) at idle or around 0, depending on the source of the PID.

 

Recommend capturing a log of the engine parameters with FORScan so you can see what is happening during the power loss. Make sure you are using the PIDs that are supported. I see some there that are not.

What is the fuel pressure at idle and under load? Would be good to rule that out.

Have you cleared the codes and seen what comes back? Want to make sure we are dealing with current codes.

If you have not been under the valve covers, I would definitely take a look under them, and verify the condition of the UVCH - do the 50 cent mods while under there. Pull each of the connections - UVCH on both sides of the gasket, and the 42 pin connector - look for burnt/damaged contacts.

Very curious that it would not start with ICP sensor unplugged. Would like to see what IPR% and FUELPW were commanded during that event.

 

Yes, as stated I cleared the codes and they did not return when I checked after coming back from dropping fuel and was running poor.

I will be checking the MAP and hose along with wiring shortly.

The no start with the ICP had me stumped too, but thought maybe it's an Excursion thing as there's more monitoring on them than a regular truck like my F350. You are wanting me to look at IPR and FUELPW with the ICP disconnected when trying to start, but just spinning over and not firing? I did this while the truck was warmed up and having the knock so I will disconnect the ICP again while cold when I check the other items above and see what happens.

This issue seems to occur when driven a dozen or so miles and the engine is completely warmed up now, though in the beginning it was just an occasional intermittent knock. This, along with a good buzz test is not leaning towards valve cover harness issues to me.

I believe the low MAP readings are because of the tune I have in the trucks as I hooked both trucks up and get the same low MAP readings.

So I also checked the codes this morning and see the P1670 (Electronic Feedback not Detected) came back. So this along with the no start with ICP disconnected is leading to something...just not sure what at this point...

 

Go here: https://www.ford-trucks.com/forums/1...-7-3l-psd.html and scroll down to Forscan instructions. This will tell you how to record a live data stream. This will tell a lot more about what's going on than a snapshot in time.

 

I can get to the streaming graph with the engine running, but to me it shows the same thing I posted minus a video...which I don't know how to capture, other than on my phone...

 

You can record the data and export it into a CSV file (the instructions explain this) and import it into BWST's PID graphing spreadsheet. It ends up looking something like this:

 

Thanks Agate Flats, I'll look into that when I get a chance. So as mentioned above I checked both trucks with Forscan and also had the P1670 code come back, which I cleared. I checked the driver side 42 wire harness over the valve cover and there doesn't appear to be any chaffing in the foil cover wrap. I disconnected the ICP again to look at the pin connectors where I read a post about where they came out of their locking position. So it looked good and leaving it disconnected I decided to see if it would start...well, it fired right up! I may leave it disconnected and take it for a drive and see what happens...

 

Okay, so I drove it in the neighborhood for a couple miles to get some heat in it with the ICP disconnected after it started and came back home to let it set for an hour or so. I went back out and tried to start and it would not fire. I reconnected the ICP and it fired up. I installed a good spare ICP and left it disconnected and it would not fire, then connected it up and it fired so I drove it another couple miles around the neighborhood and when I returned to the driveway I can hear a faint knock so I pulled the plug on the ICP while running and the idle jumped a bit and then settled back down and the knock is still there. Shut it down and reconnect the plug and it fires up. So I get my laptop to check codes again and there's a new code...P1280, which I believe is the IDM. The only other code was for the glow plug module which I know why it's there, but none of the other codes showed back up.

 

If I clear the P1280 code it will start with the ICP unplugged. I unplugged the IPR and it had oil within the plug so I took some cleaner and sprayed the plug and solenoid, let it dry, plugged it back in, and still makes the knocking. I took another look at the wires coming off he ICP and IPR and don't see anything sticking out. I made a couple videos and the this one seems to be the best in hearing the knocking.

 

I want to make sure we're talking about the right parts here. Oil in the IPR plug is not common. Oil in the ICP sensor plug happens when the ICP fails sometimes.

ICP sensor is on the driver's side bank. IPR valve is screwed into the back of the HPOP. Are we in agreement?



P1280 is typical if the ICP sensor is unplugged. That engine is idling pretty smooth. I hear the knock, but it sounds different from an injector knock to me - hard to tell.

 

Yes, we are in agreement on the sensors. I found it odd the IPR plug had some oil in there...I cleaned it and made no difference. I have a new IPR on the way...be here later today...but I also have a spare I may at least change out the front magnet behind the tin nut and see what happens...

 

A little update...

I pulled the tin nut, spacer and magnet thinking the IPR magnet may be deteriorating given the age and 247k+ on the truck. I have a good spare IPR and checked both magnets and they ohm purdy much the same value. I went ahead and drained the HPOP reservoir and pulled the IPR. I believe to have found the problem as it appears gummed up given there's no rattle when you shake the unit...whereas the spare I have does the shake rattle. I have a new one coming which will be here shortly, so I decided to just leave it be until I get the new the one and install it back in place...