First off. its a 2000 f250, 7.3 with 6spd manual. Reman PIS injectors and dp tuner chip about a week or so ago. also new fuel filter and oil change, full tank of fuel etc.

It has what sounds similar to a fuel knock. It also wanders rpm at idle, worse when warm. Its also more pronounced if i try to hold the accelerator to about 1500 rpm and not move it. the rpm will drop down to 1200-1300 for a couple of seconds then come back up, then go up to like 1600-1700 for a few seconds and come back down. etc.

im more concerned with the fuel knock noise and the errors (ill get to)
truck does not feel like its missing (it did once for a 1/8-1/4 mile one time a month ago.)

problem existed before and after new injectors/chip and oil change. no change at all.

so i got an AE to not waste more money on parts that are not the problem.
did a buzz test, contribution test and followed the guidelines to test for a problem with IPR and IPS.

injection pressure tests seemed good.

contribution test showed fault with #3 and #8, i thought that was common.

buzz test made all the noise like i thought it should (never done it before or on any other engine) but returned these faults.

p1271 Cylinder 1 high to low side open
p1272 2
p1277 7
p1273 3
p1274 4
p1275 5
p1276 6
p1278 8
p1293 injector high side open - bank 1
p1294 injector high side open - bank 2

these showed up in the test results section, not in the stored dtc or anything. do they show up just because i ran the injectors with the engine off simply a side effect of the test? or do i have a bad harness/harnesses/idm?

 

Those are codes that are stored in the IDM. They won't show up unless you either do the KOEO test or Injector Buzz test. Those usually go along with a bad connection in the UCVH. But you will usually only get a code on one bank, so this points to the big plug that connects between the IDM and both UCVH's. Or an IDM problem. But what gets me is those issues usually cause a misfire. Unless the miss fire is subtle enough to sound like a fuel knock?

 

The only time I've ever gotten all those at the same time was when I ran a buzz test with an injector breakout box installed. I can't say for sure whether it was due to the added length of the wiring, or the poor shielding. Have you cleared the codes and ran the test again to see if it repeats? Have you checked the wiring harnesses for damage?

 

well, i was thinking big plug or harness as well because of the fact that it is both heads. it had missed on me noticeably once before but not since.

so how do i go about testing the harnesses? btw, did NOT change the uvch when i did injectors, i assumed if it wasnt a dead miss, how could it be electric.

do the codes in the IDM clear when the battery power is removed the same way it clears from the PCM? i tried started the truck on accident with the big connector unplugged but have since had the batteries unhooked for a whole weekend.

 

i have not cleared them and tried again.
i did visually inspect the wires and nothing jumped out at me. the drivers side valve cover had the paint rubbed off where the bundle starts going towards the fender but was already protected by the wire loom at that point and did not look rubbed through.


EDIT; i have cleared them and tried again the injecter faults are all gone. (did not start or drive the truck)
but there was a p0605 code that i did not see the first time. did not use the blanket koeo test before. the p0605 was there before the clear and showed up again after.

 

Start the truck or run the buzz test to see if the codes return. Do you know what the new code is?

 

The P0605 is PCM ROM failure, and is normally a very bad code, but it could be caused by addition of the tuner. If you remove the tuner and the P0605 doesn't return after clearing DTCs, it's most likely nothing to worry about. Otherwise this is the only thing the Ford PC/ED says:

 

ok, ill clear up exactly what i did through the last couple posts.

i posted on here.
ate dinner
was asked if i cleared the codes to see if they remain
i went back outside
double checked the codes before i did anything else
thats when i noticed it had the p0605 in addition to the other 10 codes, (i probably just didnt see it the first time.)
cleared the codes.
KOEO test
p0605 with no other faults
buzz test. no faults
cleared codes again
started truck
cct for the fun of it - 3 and 6 fault
KOER test. for the fun of it - pass
shut truck off
KOEO - p0605 with no other codes.

if it really is a p0605, how could the truck start run and drive?

will remove chip tomorrow and check codes again. however it is my understanding i cant run the truck without the chip with the single shot injectors, correct?

is this unrelated to my noise and wandering RPM?

 

Yea, driving it will be a problem. But I think you can still do the KOEO test with out any problems.

I don't know if that can be the cause of your issues or not. It might just be a problem with the tuning. It's rare any one has any issues with the tuners you'll hear everyone here using, however it does happen with custom tuning sometimes. Usually an easy fix. Did this start as soon as you installed the chip? If so put in a trouble ticket with DP-Tuner and maybe they can atleast help you diagnose the cause of the problem.

 

the noise/rpm thing was there before the tuner. it was actually a lot of the reason i decided to replace the injectors with the mileage i have. and therefore if im replacing them, i might as well buy stages 1's and tuner.

the p0605 code, however, i dont know if it was there before or not as i just got my AE in the mail yesterday.

 

Ignore the 0605 and move on. The KOEO and KOER conduct tests that were never intended to have a chip on the connector, so it doesn't see some stuff it expects to see.

Getting back to the knocking, I am contemplating doing a write-up on knocks because there are so many sources of this. Have you done your in-tank mods? Did you know the DP performance tunes are louder than some of the other vendors? Have you tried the "stock" tune on the chip? Ask Jody to quiet the tunes down, he's done it before.

The truck will absolutely run all the live-long day without a chip... just be prepared for a touchy throttle and a terrible idle. I'm not guessing here. I had a chip failure 400 miles from home this spring, and I had to pull the chip to get going again. I drove 400 miles from the Oregon coast to central Washington with no chip - and Stage II (100% nozzles) single-shot injectors. With 100% nozzles on a stock tune - 0-40 MPH totally blows (the "throttle" becomes a switch), but freeway speeds are fine... just don't use the cruise control.

Those old codes could be from clearing the cylinders. How was the engine cranked - by shorting the starter relay or turning the key with the 42-pin connector off?

With HEUI injectors, a miss doesn't have to be a "full" miss. Partial misses exist, and they are subtle. This is what is known as an unbalance... and it can be seen when the vehicle has dual EGTs (like Stinky).

Knocking is a subjective thing - these trucks can make odd knocks with absolutely nothing wrong, but it's best to track down all the known causes of knocks before just accepting it.

 

ok, UPDATE

I have not done the in tank mod.

the noise is the same in the stock tune or not in the stock tune. it did it even before the tuner for a couple of weeks.

i unplugged the injection pressure sensor today. did not change a thing. the noise, the surgy idle, the way it drove. absolutely no change.

when i went to unplug the ips, i noticed there was a plug unplugged (broken clip) on the back of the fuel bowl (water sensor? fuel heater? white plug end into black device) plugging it back in changed nothing.

hooked a fuel pressure gauge to it. 55 pounds at idle. 40-42 in hottest tune WOT while driving of course.

uploaded a youtube vid of what it sounds like. let me know if im making something out of nothing.

 

It sounds just like my truck with a little bit of hissing. The minimum fuel pressure you want to maintain is 42 PSI. I don't know if hitting 40 is enough to be an issue or not. But if you can free up a few more PSI in fuel pressure, why not.

 

i have no idea what that hissing sound is in the video. but i did not hear it untill i rewatched the vid. im almost certain my truck is not making that noise. maybe i had a whistler in my nostril? no idea.

i dont know if fuel pressure was all the way down to an actual four zero either, it might have been, but the gauge was laying up against the windshield held by the wiper. i was doing the best i could to read it. looked to be good side of 40.

 

Tugly is the one who seems to know the most about knocks, thuds, rattles and ect. Maybe he'll give some input. But it sounds good to me.