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Dantheman1540
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Yes.........
Mostly on cold starts but it doesn't discriminate and will get me on a warm start sometimes too.
2004 6.0 NV4500 Tahoe
- Thread starter Dantheman1540
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Mostly on cold starts but it doesn't discriminate and will get me on a warm start sometimes too.
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Dantheman1540
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I got HPT to read over 6k but I wasn't able to see what the dash was reading at the same time, I guess I need to do a deliberate pull to 6,800 dash read out and compare it to the HPT log.
@randeez I sent you two new log files, one is a cold start idle warm-up with no accessories on and the other is my ride home with a couple of high rpm pulls in second gear.
@randeez I sent you two new log files, one is a cold start idle warm-up with no accessories on and the other is my ride home with a couple of high rpm pulls in second gear.
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Dantheman1540
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Huh one thing I just noticed is that I didn't have the BIAF In gear and P/N the same. I'm fairly certain in the past I had them the same but I guess not anymore. I'd assume the truck looks at the P/N row since it doesn't know it's in gear so I will copy them over. If I have been changing the wrong thing I'm gonna feel pretty dumb
George B
¯\_(ツ)_/¯
A simple and overlooked fix is always welcome.
randeez
Full Access Member
it looks like it cold starts fine lol
the misfires look bad though, you make sure theyre all plugged in n stuff? wires pretty new? whenthe last time you checked plugs
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Dantheman1540
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If it fixes anything lol.
the misfires make no sense to me I don't not feel anything every and the plugs looked great 2 months ago. The wires are kinda mismatched junk but I inspected them when I checked out the plugs and nothing looked bad, I did not OHm them out tho.
The cold start is steady but why does it start and initially idle at 16-18afr? The commanded is clearly 14.7 and eventually, it gets down to that but the first few minutes it's super lean and if I start driving during that period it usually swings even leaner I've seen 20s or it dives down crazy stupid rich like 9.
Maybe all this is related to some strange ignition issue like a bad coil pack causing misfires which throws everything else off? Maybe I need to nut up and buy some decent plug wires for once.
pwtr02ss
Full Access Member
I've had the best luck with OEM wires. The "original equipment" type. I had 2 sets of MSD wires on my camaro and they would randomly misfire. Real treat when the engine is fresh and you're chasing your tail...
randeez
Full Access Member
if youre using pump gas (E10) set the stoich to 14.10840 under fuel>general>stoichiometry
it starts (the first couple seconds) rich. you can stretch out the table under fuel>open loop/base>eq ratio over 68* its calling for 1.0 eq (no adder) when you start it over that temp it wants to dump right into 1.0eq. maybe stretch some adder to 100*+
it starts (the first couple seconds) rich. you can stretch out the table under fuel>open loop/base>eq ratio over 68* its calling for 1.0 eq (no adder) when you start it over that temp it wants to dump right into 1.0eq. maybe stretch some adder to 100*+
randeez
Full Access Member
mine would misfire with the maf connected... soon as i ditched it all the misfires when away. i have absolutely no clue why
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Dantheman1540
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Yeah, I have like 3 MSD wires, maybe 2 OEMs, and then 3 random other brands that are red but not MSD. It's kinda a cluster but I have a huge pile of wires and can't stand not using stuff I already have.
I'm gonna get those $130 ceramic boot short ones next go aroud, maybe they will stay together.
Stoich is now set to 14.1 what do you mean stretch the table out? You mean ad some gradually going up in temp so at 68* maybe make that 1.03? or subtract some making it .97?
I remember you posting about that, mine does it maf or no maf unfortunantly
randeez
Full Access Member
I would copy the three cells with 1.04, 1.08 and 1.12 and move them over to the 86 column (same row)
at the bottom of the 86 column i would put it in like 1.2. then smooth from the 1.2 up to the 1.12. and then smooth it back to the 68 column. let me know if that makes sense
since your map is pretty stable at 50-55kpa that is where the most of the warm up eq is going to be. but if truck is off (100kpa) its going to run along those cells for first second or two till it gets there. the 14.1 stoich value is going to richen up the adder also (and will prob make your wideband display more accurate.
before you were telling it all fuel was a stoich of 14.7, when in reality E10 is 14.1. so if youre targetting E10 @14.7 youre lean. hence the wideband showing lean @15+ after it comes up to temp. the wideband doesnt "read" in air to fuel ratio, it reads lamda. and just spits out a display based on what scale your using gas scale is 14.7=1
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pwtr02ss
Full Access Member
damn. You impress me with all this tuning knowledge you have.
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Dantheman1540
Full Access Member
Makes sense, I had heard about that 14.1 stoich value before but I guess I didn't absorb enough to make me do anything about it. The above post has more usable info than 99.96969696969% of posts on the HPT forum.
Everytime I learn something new
Hows this look Daddy?
randeez
Full Access Member
we havent started tuning yet lol
this is just the ol garbage in= garbage out
a lot of this is math, so its easier to explain when i can give him numbers instead of well i want it to be 12.8, so multiply by 1.08 adder, but since youre using an offset afr you need to put in 1.10. its not that it cant be done with incorrect info but some of these tables you literally need to only adjust a hundredth/thousandth place value so that .005 difference makes a difference
randeez
Full Access Member
yep, try it an see...should hang the afr a little richer, longer. "colds" starts are still 65-70* right?
theres the table to the right that says startup decay or something like that. im wondering if that table holds the enrichment value that you just rised for that duration. as long as it hits the cell or if the decay is a stop for it only allows it to work if its in the cell for that time. but may play with that one after if it stays rich for too long
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Dantheman1540
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Yeah even overnight the 6 hours the truck sits it rarely gets below 60ect and I have been a good boy about starting it 5 minutes before I leave.
randeez
Full Access Member
log whether its commanding closed loop or not also
pwtr02ss
Full Access Member
This is why I have such a hard time staying focused on this shit. You feel good about something then next thing you know, you're lost.
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Dantheman1540
Full Access Member
Roger, closed-loop active channel added.
It's even more fun when stupid hardware issues pop up like a log not recording half the data you need, or a sensor being slow to warm up. But you need to try to learn because knowing is half the battle
pwtr02ss
Full Access Member
Coming soon big D. My camaro needs some fine tuning too. Its Gen 3 thoughRoger, closed-loop active channel added.
It's even more fun when stupid hardware issues pop up like a log not recording half the data you need, or a sensor being slow to warm up. But you need to try to learn because knowing is half the battle
