Where Are The PER_DEL PIDs: Act 2

8WA Sman · December 21, 2014

New customer brings in a '01 F-250 with an Edge Evolution and want's me to change the IDM because he took it somewhere for a high RPM trans shift complaint. I really do not like changing modules on another shops diag and I tied to talk him into letting me diag the truck first. Long story short he still wants me to go ahead and put an IDM. I test drive the truck and it definitely has a high shift point but it also seems like does not have the power it should. I then I pull the truck inside and pull code just out of curiosity I get a P1668(IDM to PCM Com problem). I also get 4 quiet buzzes when I do the injector test :chinrub2: .

Now it's time to install the IDM and I decide to ohm out the injector circuits @ the IDM because if there is a circuit issue that burns up "My" IDM then I will be in the middle of a blame game(This brings me back to one of the reasons I usually don't do jobs like this :scratch: ) I have high resistance on all injectors on Bank 2. I get ahold of the customer and get the go ahead and diag the circuit issue on Bank 2. Of course the UVCH is almost disconnected on Bank 2 causing the high resistance, 4 quiet buzzes and low power. Still does not explain the P1668 but customer still gest an IDM installed. Well surprise the P1668 is still there and will not clear

I also notice that I have No PER_DEL pids and thanks to DTS I know for a fact that anything but the early build 7.3L should have PER_DEL "Thanks"

I call Edge to find out if their chip could be causing this problem,they say to do a reflash and they will reset the dash pod for me. I try to do a update and I get this

I check the log file and I see that the PCM is a F81F,in an '01 that can't be right

So I run the Vin in FCA and the part number for this trucks PCM should be a 1C3F-12A650-ZB. I find out that the customer had a '99 truck before this one and that this chip came out of the '99. I get the Vin for his old truck and "surprise/surprise" the PCM part number was a F81F-BF. So I either have the wrong PCM or I have the wrong file in his current PCM. I access the info directly from the back of the PCM and I find his truck has the wrong file loaded in his PCM. So I load the correct file into his PCM and now wouldn't you know it now I have the PER_DEL pids back

I have no codes

And the truck shifts just like it should.

I hope everyone has as much fun reading this as I had fixing the truck because I had a blast :partay:

Keith Browning · December 21, 2014

:haha2:

Don't you love shit like this!

Matt Saunoras · December 21, 2014

I had my own little experience with a chip and P1668 on a late 99 7.3 recently. Found the chip had loosened up causing a wide variety of issues but regardless as long as it was plugged in it would set a P1668. As soon as I removed it the code cleared itself.

The customer didn't want to hear it though. The truck was sluggish when stock but the up-pipes were leaking bad enough you could hear it in the cab and the wastegate was frozen. It wasn't making full boost that's for sure. Ran good with the chip installed so back in it went. :rolleyes:

8WA Sman · December 21, 2014

Matt, if you are talking about the style of chip that plugs into the back of the PCM,those are nothing but trouble and they can end up breaking the circuit board.

Matt Saunoras · December 21, 2014

Yup that kind of chip

Bruce Amacker · December 21, 2014

P1668- isn't that the ghost code that '99s get? There was an updated IDM for it or something?

Reminder- No Perdels until late '99 trucks, early 99's and Gen 1 7.3 don't get them....

:grin:

8WA Sman · December 22, 2014

My guess is that the P1668 set because the KOEO voltage reading on PCM pin 48 was out of spec for the early build calibration file that was loaded into the PCM. My guess is that the wrong file got loaded into the PCM when the Edge tuner was swapped from his early build '99 to his '01 truck.

I also found out that Edge builds off of the stock file, which I found interesting. Which makes sense because they just change some of the mapping. Why is this important? I am by no means a fan of tuners but if someone does have a tune in their vehicle it may still be a good idea to update the calibration files then load the tune back in.