DBW 6.0 swap dies when coming to a stop, no VSS
11-17-2017, 06:34 PM
#1
DBW 6.0 swap dies when coming to a stop, no VSS I'm struggling with this as it's the first DBW swap I've tuned.
73 Chev 4WD PU with a TH350.
Truck now runs sweet after tuning it. WOT done with the AFX WB, part throttle stuff the same. Although the trims aren't all that happy using WB correction data.
BRAF is set and happy.
This is a MAF only tune.
Anyway, sometimes, not all the time, the truck will die when coming to a stop.
I can see the underspeed timing trying to keep it alive by increasing timing.
But at the same time it's closing the throttle down to 1.6% when the normal idle opening it approx. 10%. it's as if the two are fighting each other.
It does have an LS6 cam, but that cam is really mellow.
Idle set to 800.
I'm thinking since the thing thinks it going 0 mph all the time, the adaptive idle routines get confused.
Any work around for this in the tuning?
Ron
73 Chev 4WD PU with a TH350.
Truck now runs sweet after tuning it. WOT done with the AFX WB, part throttle stuff the same. Although the trims aren't all that happy using WB correction data.
BRAF is set and happy.
This is a MAF only tune.
Anyway, sometimes, not all the time, the truck will die when coming to a stop.
I can see the underspeed timing trying to keep it alive by increasing timing.
But at the same time it's closing the throttle down to 1.6% when the normal idle opening it approx. 10%. it's as if the two are fighting each other.
It does have an LS6 cam, but that cam is really mellow.
Idle set to 800.
I'm thinking since the thing thinks it going 0 mph all the time, the adaptive idle routines get confused.
Any work around for this in the tuning?
Ron
11-17-2017, 07:26 PM
#2
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Set your lower cells to your idle g/cyl. For example, if 3150 is 8 g/s, set all the lower cells to 7. Then you’ll have fuel
11-17-2017, 08:00 PM
#3
I'm struggling with this as it's the first DBW swap I've tuned.
73 Chev 4WD PU with a TH350.
Truck now runs sweet after tuning it. WOT done with the AFX WB, part throttle stuff the same. Although the trims aren't all that happy using WB correction data.
BRAF is set and happy.
This is a MAF only tune.
Anyway, sometimes, not all the time, the truck will die when coming to a stop.
I can see the underspeed timing trying to keep it alive by increasing timing.
But at the same time it's closing the throttle down to 1.6% when the normal idle opening it approx. 10%. it's as if the two are fighting each other.
It does have an LS6 cam, but that cam is really mellow.
Idle set to 800.
I'm thinking since the thing thinks it going 0 mph all the time, the adaptive idle routines get confused.
Any work around for this in the tuning?
Ron
73 Chev 4WD PU with a TH350.
Truck now runs sweet after tuning it. WOT done with the AFX WB, part throttle stuff the same. Although the trims aren't all that happy using WB correction data.
BRAF is set and happy.
This is a MAF only tune.
Anyway, sometimes, not all the time, the truck will die when coming to a stop.
I can see the underspeed timing trying to keep it alive by increasing timing.
But at the same time it's closing the throttle down to 1.6% when the normal idle opening it approx. 10%. it's as if the two are fighting each other.
It does have an LS6 cam, but that cam is really mellow.
Idle set to 800.
I'm thinking since the thing thinks it going 0 mph all the time, the adaptive idle routines get confused.
Any work around for this in the tuning?
Ron
11-18-2017, 06:40 PM
#5
So this helped, thanks. The rpm was still dropping to as low as 500 but it kept running.
I added some throttle follower and it seems fixed.
But, the throttle still closes way down, when it seems like it should not go that low.
I'm sure VSS would fix all of this.
I honestly hate DBW.........
On my Nova, was never an issue with the cable TB. But still acted a bit weird. So I added VSS to the TH400. Worked like a charm.
Ron
I added some throttle follower and it seems fixed.
But, the throttle still closes way down, when it seems like it should not go that low.
I'm sure VSS would fix all of this.
I honestly hate DBW.........
On my Nova, was never an issue with the cable TB. But still acted a bit weird. So I added VSS to the TH400. Worked like a charm.
Ron
11-18-2017, 08:36 PM
#6
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Its funny. I had the opposite struggle on my wife’s vette. Couldn’t get it to idle DOWN until a dead stop. Scalar, follower, etc made very little difference. Finally ended up setting max area lower to make it stop. And bumping up the adaptive idle max speed. This was following a fast and NW 102 on a ls2.
Anyway, glad I helped a little.
Anyway, glad I helped a little.
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11-19-2017, 11:16 AM
#8
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Gen 4 ecu. No cracker or follower speeds. Only VSS enable and hysteresis for adaptive idle. It’s up at 400 kph. Follower Max air dropped from 12-3 and max area dropped from 2.3 to 1.6
11-19-2017, 11:57 AM
#9
Thanks guys. I think it's good enough as it is.
He is going to replace the factory intake ducting set up with a simple tube and elbow which will mean retuning the MAF a bit anyway. So I'll revisit things then.
I thought about raising the min throttle area, but that's one of those settings that HPT says change at your own risk......so I'd rather not brick his ecu.
Ron
He is going to replace the factory intake ducting set up with a simple tube and elbow which will mean retuning the MAF a bit anyway. So I'll revisit things then.
I thought about raising the min throttle area, but that's one of those settings that HPT says change at your own risk......so I'd rather not brick his ecu.
Ron
11-19-2017, 02:59 PM
#12
Appreciate the comments.
Idle is tough on these without VSS
Fortunately he has a 2800 stall converter.
He picked up the truck today, and he is quite pleased. Which is my goal as a tuner.
I retired from the tuning shop I worked for, got tired of Dodges. And at 62 years old, got tired of the wrenching.
Happy to help my buddies. I also tune his 79 Malibu wagon that has gone 8.71@158.
Good buddy deal as always.
Ron
Idle is tough on these without VSS
Fortunately he has a 2800 stall converter.
He picked up the truck today, and he is quite pleased. Which is my goal as a tuner.
I retired from the tuning shop I worked for, got tired of Dodges. And at 62 years old, got tired of the wrenching.
Happy to help my buddies. I also tune his 79 Malibu wagon that has gone 8.71@158.
Good buddy deal as always.
Ron
11-19-2017, 08:14 PM
#13
11-19-2017, 09:25 PM
#14
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Originally Posted by subeone
increase the enable speed to 50 mph. Works the same.
