I think we all want a resolution as much as you do.
CK5
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8.1/LS swap no start issues, help needed
- Thread starter Kay86K5
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Yes, this morning. He said there may be a hardware issue with the computer itself. We are debating that I send the computer back to them and they can run some tests on it to see if there is an issue they didn't catch when installing the software tune on it
The only thing that confuses me is Alex had another 8.1 computer that we brought with him, we looked at that tune and decided there wasn't anything that would have stopped it from starting up my 8.1 application, so we plugged that one in to my harness/motor. That computer, along with the other coil packs, was doing the exact same thing as my computer and my coil packs...only 1 coil pack firing...and it was the same coil pack everytime, no matter what combo of coil packs and computer 
That sounds like there wasn't any tune on the ECM besides the factory one.
Sounds like the only thing you haven't eliminated is a wiring harness issue.
Both computers doing the same thing.. I don't know how the coils are wired, but if they're back to a single point - maybe start there.
That's kinda where we are at...
The only weird thing about this, is we pined every single coil pack connector. Each connector has 4 wires on them, we looked at a schematic and found which port on the ECM each wire should go to and pined each one to make sure it was going to the correct spot....and each was correct. And we confirmed each coil pack is getting 12v power just fine, but only 1 coil pack is getting the fire signal from the ECM....but a completely separate ECM and set of coil packs hooked to my harness is doing the exact same thing....this is getting beyond weird
Team208Motorsports
Its Magic Bitch
Howell does not performance tune anything. They turn crap off to make things barely run............. A bad gen 3 ECM is a very rare thing unless it was bricked while tuning. They are very tough. If a second ECM does the same thing, its time to look at the harness or the base tune is flat out wrong. Is this a drive by cable conversion? They have their head totally up their ass with those.
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Yeah, I am betting on a wiring problem as well with either something being pinned wrong, poor ground, etc. I’ve sparred with Troy before with issues and they can be very hard to work through problems on until you absolutely prove the issue is on their end.
I’m with Alex where I don’t see this being a tuning issue. Every tuner thinks they are better than the last and Howell’s tunes certainly are not the best by any means especially with maximizing performance but they are drivable and reliable and better tunes than I’ve paid hundreds of dollars in live tuning by a “expert” tuner. I’ve got 7 years and almost 40,000 miles on the Howell 8.1L drive by cable tune in my K10 and it starts, goes and goes well. My Suburban is now going on 9 months with the same “crappy” 8.1L drive by cable tune and it runs like a top as well. Howell basically uses an early LM7 5.3L tune (cable throttle body) with 8.1L specifics loaded over it.
I’m with Alex where I don’t see this being a tuning issue. Every tuner thinks they are better than the last and Howell’s tunes certainly are not the best by any means especially with maximizing performance but they are drivable and reliable and better tunes than I’ve paid hundreds of dollars in live tuning by a “expert” tuner. I’ve got 7 years and almost 40,000 miles on the Howell 8.1L drive by cable tune in my K10 and it starts, goes and goes well. My Suburban is now going on 9 months with the same “crappy” 8.1L drive by cable tune and it runs like a top as well. Howell basically uses an early LM7 5.3L tune (cable throttle body) with 8.1L specifics loaded over it.
Sounds like you might need to load test your wiring instead of just ohming it out or checking power and ground with a meter. You could have a slight connection but not enough when under load.
ROFL so.. how do you really feel?
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You said you moved the coils around to test and got the same cyl's to fire right...? So it's not a coil pack. And you swapped ECU's out, so it couldn't be the ECU.... Gotta be wiring. Unless both ECU's have been programmed and screwed up the same.
Team208Motorsports
Its Magic Bitch
This shows they do not understand the basics of how a gen 3 ecm works.
I love you too LARRY!! Sorry you are jaded by amateur hour and can't tell the different between who you should and shouldn't give your hard earned money to. You can jab at me all day, it makes no difference. Just shows you are biased in every swap decision based on your experience only. Here comes the bla bla bla part.
In all reality, they can do a conversion but what defines a successful conversion for most places? Usually its if it fires and runs. That's it. That's how far your money takes you.
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Hey dude, sorry it hurts your feelings but it is true even on a OEM level where each tuner talks smack about the last guy. I guess it is the nature of the art. I work for a truck and engine manufacturer where even our calibrators (they’re not called tuners at the OEM level) always take issue with the last person that set up cal files in various vehicles. Right now I am working with two airport refuelers on an air force base that keep ramping up the idle for EGR flow rate and HC Desorb when the Regen inhibit switch is turned on and PTO is engaged, which is not good to have the idle going above a certain RPM when pumping jet fuel. 3 different engineers have played with the calibrations and each make snide comments about the last person that touched them. Same thing when we were building GM powered UPS trucks. When the 6L90 came out we had trucks that would not shift out of 3rd gear at WOT. The GM Powertrain calibrator that was helping us resolve the issue repeatedly commented how the calibrations where so far out of whack. The next GM calibrator that came to the Bosch Proving Grounds to test the UPS units commented on the last guy that commented on the production calibration files. No different that we all see in the aftermarket side as well. I feel there is just a lot of pride in tuning/calibrating where everybody has the opinion their work is better than the last guy....always! The strong comments you make regarding everybody else’s tunes in every thread reinforce just that.
As far as mine, these guys weren’t just some guy running a tuning shop out of his home garage. They are pretty well known around the state and came highly recommended with magazine articles, featured vehicles, etc. They did a great HP tune on a dyno but didn’t give one care of the smoothness of the overall drivability mainly because they want to make a quick $500 on a dyno for 2 hours work then send you away.
And as far as what defines a successful conversion…. Well, yeah….if the vehicle starts and runs, runs well, no ghost codes, no oddball drivability issues, runs well at -150 ft. elevation through 14,000 ft. and everywhere in between and proves reliable at then I call that successful even if the tune isn’t 100% in the eyes of a tune critic.
I wish you were closer as I would love to have you do some tuning on mine as I know you would do it right, because you said you’re the best. If you said so, it must be true.....
The interesting thing about tuners is the end product. I have seen Josh retune alot of well known guys tunes. Including Pac Fab who seems insanely popular and have seen guys get out of cars and just be blown away at how much better it runs.
I have also seen him diagnose other issues with the car just by looking at the tune.
Of course this is mostly with race vehicles, so getting every last bit of possible performance is the goal, but in ultra 4 the car running as smooth as butter at idle and not having any issues up and down the throttle is also very important.
I have watched guys just accept the fact that their cammed up motor dies and runs terrible until they get above 5k cause well it's got a cam. Which is the problem. I think the bar has been set so low for tuners that people have accepted things they really should not have. And that includes companies like Howell and Pac Fab and turnkey, 150 tunes, and a host of others.
I really don't think Josh will get back to this thread for a bit. He is on his way to China. Tuning on and keeping up several ultra 4 cars
http://ultra4racing.com/the-inside-line/ultra4-heading-china/
I really think people need to expect more from tuners. But the tuning industry has somehow convinced people that mediocre is as good as it gets. Shoot in many cases I have seen, they have convinced people that barely running is ok.
But for some reason I rarely see tuners getting called out on their crap.
Anyway back to your regularly scheduled programming about what is actually wrong with this particular 8.1 swap
I have also seen him diagnose other issues with the car just by looking at the tune.
Of course this is mostly with race vehicles, so getting every last bit of possible performance is the goal, but in ultra 4 the car running as smooth as butter at idle and not having any issues up and down the throttle is also very important.
I have watched guys just accept the fact that their cammed up motor dies and runs terrible until they get above 5k cause well it's got a cam. Which is the problem. I think the bar has been set so low for tuners that people have accepted things they really should not have. And that includes companies like Howell and Pac Fab and turnkey, 150 tunes, and a host of others.
I really don't think Josh will get back to this thread for a bit. He is on his way to China. Tuning on and keeping up several ultra 4 cars
http://ultra4racing.com/the-inside-line/ultra4-heading-china/
I really think people need to expect more from tuners. But the tuning industry has somehow convinced people that mediocre is as good as it gets. Shoot in many cases I have seen, they have convinced people that barely running is ok.
But for some reason I rarely see tuners getting called out on their crap.
Anyway back to your regularly scheduled programming about what is actually wrong with this particular 8.1 swap
I wish I could tell you what is actually wrong with this particular 8.1 swap 
I wish I could tell you what is actually wrong with this particular 8.1 swap
Has to be the harness or some weird ground issue after your last round of troubleshooting. The power dip was suspect but it sounds like @Team208Motorsports thinks otherwise which I have to believe is true based on his background.
I wish I could tell you what is actually wrong with this particular 8.1 swap
So when faced with an unusual problem sometimes best to start over. Find a different source for the pinouts and wiring diagram. Just go back and look at the most basic stuff .
I know it sounds weird but ignore the actual problem and just check everything.
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I wish I could tell you what is actually wrong with this particular 8.1 swap
I spoke with Alex last night. I feel he is on to something with the potential issue you are chasing a resolution on related to the CMP. Anxious to see how that works out
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that's interesting.
