*LONG WINDED POST WARNING*

Well guys, I believe some PMS is beginning to set in. My truck has been running well, but here lately I have been noticing some higher EGTs than usual, and I don't seem to be building boost like I use to (via MAP, I do not have a dedicated boost gauge yet). Granted this change seemed to happen after I got in the throttle and threw the MIL light for a couple seconds, so I may have thrown it out of wack.

Anyway, I am looking into getting the truck looking and performing better. First off, I am debating on going with different tuners to see what else everyone has to offer (Would get the Hydra. I am looking at possibly Gearhead tunes). There is a hydra for sale in the parts for sale area currently, so this may very well be the time to experiment with different tuners to see where performance/egts will land. I would like to keep my Infinity, however, as it comes in handy for diagnostics, OBDII gauges, and as a switcher.

I am also looking to get the truck itself looking better. I believe my front springs are sagging, as I measured frame-to-shackle to be 2.5" apposed to the average of about 4-4.5" that I believe Tugly found in his research. I have been holding out on doing shocks (Have had cupped tires for awhile) as I do not want to put brand new shocks on only to have them wear prematurely due to weak springs.

One of the last things I am currently looking at doing is fixing my bed rust. I have some rust through on the fenders beginning, some rust at the seam in the wheel well, and my crossmembers are shot. I have been looking at getting a flatbed and putting sides on it for when I need to haul mulch, gravel, etc. as I can get a Knapheide gooseneck flatbed installed for about 1k more than the cheapest rust free shortbed I have found for sale. I also have to take into account paint-matching for a new shortbed, in which case I may just have the whole truck redone while I am at it (Would make the truck look better and make it easier to paint match). In the below photo you can see where I am testing some implement paint I had that needed to be used as a cheaper POR15 alternative.
Here is an example of what I am working with:


EDIT: I had the above already typed up in a work document to be posted and haven't gotten around to submitting the thread. Instead of making a separate thread, I decided to throw it onto the end of this one.

I recently had a scare with the truck. I had finished doing an engine clean down and moved the truck from the washing area so I could try and get a stuck bumper bolt loose and not get soaked. Truck drove fine as usual, so I figured all was well. That was until I went to drive it that night to get fuel from Southern States. I took off and a couple of hundred feet down the road I notice the truck sounds off. Not 45 seconds later the MIL came on. Pulled to the side of the road and the truck was missing badly. Pulled codes with my Infinity and found that it was throwing an IDM code. Not five seconds after pulling that code, it clears up and is running great.

I decide that it was probably just a fluke and begin back on my journey, and about 1,000 ft up the road it does it again, but this time it doesn't clear up. I pull off the road again and find that I am throwing P0270, Injector #4 Short to Ground. I did a buzz test and all eight worked, but still had the code. I did some searching and found that a lot of times this is caused by the wires on the 42 pin connector shorting to the driver's side valve cover. With it now being dark out and my wanting to get it back to where I can work on the harness without looking like I am giving the engine a lap dance, I got a piece of cardboard and put it under the 42 pin where it hits the valve cover. Just like that, the issue was gone. No MIL light, no codes, all fine. Drove the truck home and let it sit for the night.

Fast forward to the next morning and I go out to work on it. I climb in the bay and disconnect the 42 pin connector. I look at where it rides against the valve cover, and nothing. No cracked insulation, no bare wires, absolutely no signs of wear - not even under the electrical tape. This all happened Saturday night/Sunday morning, and has been running fine since. No idea what has caused this issue, but I am wondering if it might not be my under-valve cover harnesses need to get changed (Can get Dorman gaskets with the integrated harness for about $56 a pop from work). I figure while I am in there I would check injector torque and what not. Any other insights to what could cause it?

I do think it is worth nothing that in one of the logs I ran while deciphering my throttle/fueling band, I found that IPRDC shot up to 88% at one point during a run from 45-65. I have the log file for it and can supply it if requested. I threw this rudimentary graph together in excel to help show what was going on (Don't you love dual-axis graphs?)


As always, thank you in advance for all the insights, suggestions, etc. that you all provide on here.


NOTE: I do NOT want this to turn into a tuner flame war. I do know that when asking about tuners people can get heated, but please don't post if all you are going to do is trash talk someone. I am looking for experience from people that have run multiple tuners and how they compare to each other.

 

IIRC Chris F350 had a break in the harness near the 42 pin, but on the engine side not the fender side. Same symptom different location. I'd guess a continuity test with harness wiggling is a good first step.

 

Classic graph. That's what I call a "Stinky Spike". You'll notice the ICP sucks with your foot in the throttle, then it goes bonkers when you lift your foot. The one thing that is tied to this phenomenon that you can see on the OBDII is the Fuel Injector Pulse Width. Any time you see the FIPW pop 3 milliseconds (3000 microseconds as read on the Infinity), the ICP DC (IPR) rises and the ICP drops. The farther you go above 3 ms (many 80 HP tunes usually reach for about 4.5 ms), the worse the symptoms get, and the higher the spike goes when you let off the throttle.

Here's what you feel in the pantsometer: You have a burst of go, but it fades as the RPMs climb - making you ask "Where'd my Permagrin go?". Once the next gear up grabs, the permagrin returns - but the RPM fade does as well. That fade shouldn't be there.





If you watch your FIPW while you feather the throttle and try to keep it at as close to 3000 as possible, you will discover a new power level.

Infinity will not switch a Hydra, but it will always be an OBDII scan tool and a programmer (if no chip is on the edge connector, or the chip allows the PCM calibration to come through)

 

I believe I read about his adventure with that in one of the threads I dug up, and IIRC it cost around $1100 from the dealer? If that does happen to be the problem I will just run a jumper. No sense in paying that unless all the sensor connectors melt at the same time.

Rich,
Thank you for that information, I do believe I see what you are saying now. When I let off the throttle after doing a hard run, the ICP DC takes a second to realize it needs to drop the duty cycle and causes the ICP to jump given there is no longer a load demanding such a high duty cycle.

Is it safe to assume that most tunes will have this spike? Also, I notice that you have had both the F6 and the Hydra. Did you see a decent difference when switching over? If I make the switch I think I will keep the Infinity as a monitor since I don't really have a place to fit a tablet and run an OBDII interface on my truck (dern shifter is in the way). I have also debated getting some standard gauges on the A-Pod for Boost, Fuel Pressure, and possibly some other things I can't get right off the Infinity without putting more holes in the firewall.

I also plan to build a boost leak detector to see if I happen to be letting any boost leak out before it can be put to good use.

 

Boy... I just threw that land mine down and walked right over it - didn't I.

Please scroll to the top, then look up and to the right on your screen - where you will see our sponsor.

Many performance tunes deliver the Stinky spike, and they almost invariably have the long pulse width that sinks the ICP to levels lower than intended. Tune vendors will be quick to point out the vehicle needs a T500 or the like to resolve the problem, but this doesn't work... it just makes the problem less pronounced.

To site one specific example of this (without names): The ICP dropped to 1800 PSI with an 80 HP tune at WOT with about 4.5 ms FIPW, but the stock calibration delivered 2800 PSI ICP at WOT - and the "feathered" 80 HP tune (under 3 ms FIPW) delivered 3000 PSI ICP. The T500 was purchased and installed, and that brought the ICP up to 2400 PSI with the 80 HP tune at WOT - where the feathered 80 HP tune again delivered 3000 PSI ICP.

For those asking "What's the big deal about about 2400 PSI vs 3000 PSI ICP?" Anybody who has experienced the difference will quickly tell you it's a very big deal. If asked, I can go into detail... but use the restroom first and grab a cup-O-Jo before you sit down for that read.

I have seen countless tuners on countless trucks dish up the Stinky spike in different degrees of intensity - with the common element that the bigger the tune on stock sticks, the worse it is. If you have a 60-65 HP tune with 3000 PSI ICP at WOT, you've won the jackpot. If you've climbed that ladder with bigger sticks (like me) and hit the magic 3000 PSI with no contrails - jackpot again. I have seen a tiny number of tuners nail this by email, and a few more with live tuning. I have also seen perfectly good tunes choke - because the truck was not 100%

This is where I should note that while 80, 100, and 140 HP tunes are commonly ordered by the consumer, there are usually warnings on the website stating that in order to attain those numbers - the vehicle needs to be modified. The website will even go so far as to call out for bigger air and injectors (and the vendor is eager to sell them to you), yet the consumer is more apt to just see that 80, 100, or 140 HP and go click crazy in the tune section. Saying that - our stock injectors have about 60-65 HP on the table from stock tune - that's it.

In years past, the Stinky spike didn't really matter to the driver - mostly because there was no way for the masses to know what was going on in there. Drivers only knew there was more power than stock, and they were fine with that. Fast-forward a few years and AE became affordable to enthusiasts - then hard-core power seekers realized there was still a sizable helping of oomph still left on the table. Flip a few dozen more calendar pages and anybody with 25 bucks and a smart phone is viewing this issue - akin to 1.9 million hits on a YouTube fail video.

 

Ah, that does make a bit more sense now. Thank you for taking the time to explain it in more depth. I will try my 60 tune as a DD tune and see what results of that.

On another note, had the issue with the truck again today. Shut the truck down and restarted it, ran fine. After work I was armed with two UVCH just in case. Dug into the 42 pin and tested for continuity, all checked out. Went ahead and took the valve cover off and checked for continuity there, all checked out. At this point I figured since I was in there, I might as well go ahead and change the harness out. Re-torqued all bolts while I was in there (only two were a hair loose). With the cover off I started it up and all looked well. I am going to go ahead and do the passenger side while I am at it so I know when they were last changed. I think it may be one of those hold-your-mouth-just-right things as the truck passed buzz tests fine right when the error occured (though to the trucks credit evens sounded a hair muffled, which would point to the harness).