stalling at Red lights.....
Thread Starter
Pro
Joined: Aug 2008
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From: Colorado springs
stalling at Red lights.....
This is strange, and my tuner can't seem to figure it out. When I come to a stop light the car will surge and the AFR will either go super rich or super lean, which causes the car to surge between 200 and 1k RPM. This is intermittent, but I'd say it happens 60% of the time. If I leave it alone it will sort it's self out after 10-15 seconds.
I've only had it die on me once, and it seems to do better in the cooler air. Anybody had a similar experience after going FI?
I've only had it die on me once, and it seems to do better in the cooler air. Anybody had a similar experience after going FI?
Team Owner
Joined: Jan 2007
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From: cookeville tennessee
This is strange, and my tuner can't seem to figure it out. When I come to a stop light the car will surge and the AFR will either go super rich or super lean, which causes the car to surge between 200 and 1k RPM. This is intermittent, but I'd say it happens 60% of the time. If I leave it alone it will sort it's self out after 10-15 seconds.
I've only had it die on me once, and it seems to do better in the cooler air. Anybody had a similar experience after going FI?
I've only had it die on me once, and it seems to do better in the cooler air. Anybody had a similar experience after going FI?
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
Buddy really dont want to say on that one. Do a post over in tuning and ask around. Really to get your car 100% a tuner will need your car for a few days to really work out all the bugs. Dont go by a tuner in it for 30 mins down the road and 3 pulls on the dyno crap. The WOT is the easy part here. The driveabilty part for the street and red light to light is the hard part. Robert
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Pro
Joined: Aug 2008
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From: Colorado springs
Thread Starter
Pro
Joined: Aug 2008
Posts: 574
Likes: 5
From: Colorado springs
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Tech Contributor
Joined: Apr 2007
Posts: 10,924
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From: Forney Texas
If it's not a vacuum leak, I've seen it caused by a improperly tuned car where what happens is the short term fuel trims are elevated in deceleration and then when you come to a stop, the elevated values skew your commanded fuel values accordingly but when you get down to idling, they're not needed and that demand changes. Although the trims begin to respond, they don't do it quickly enough and the engine has a difficult time until they get lined out. The next scenario is commanded airflow. When idling, the PCM will make adjustments to achieve commanded idle RPM. The second you touch the gas, the short-term adjustments zero out. If you're driving and don't have the proper commanded airflow, it doesn't know where to put the throttle blade for a moment and starts making adjustments accordingly, but not quickly enough. It's part of the PID strategy. Proportional, Integral, Derivative and can be sped up but you can be opening Pandora's box if you get lost in the adjustments, which is often not difficult to do.
Drifting
Joined: Nov 2012
Posts: 1,665
Likes: 17
From: Bradenton Florida
St. Jude Donor '13
I'd have no problem taking care of FI tuning for you. As long as everything is copacetic mechanically, no reason why I cannot have that thing idling properly for you!
I am in Bradenton FL, which depending on where in south GA it could be a long ride to me...
I also go up to Panama City and use a dyno in that area doing tuning at weekend shots. This seems to be closer to you bladeboy. I believe we (Bladeboy) had spoke originally when you had purchased that STS kit. I used to be with the crew up there at ECS. May be able to plan something out if you guys need a few tunes I can make a trip up to PC and use my buddies Dynojet 424xLC there.
I am in Bradenton FL, which depending on where in south GA it could be a long ride to me...
I also go up to Panama City and use a dyno in that area doing tuning at weekend shots. This seems to be closer to you bladeboy. I believe we (Bladeboy) had spoke originally when you had purchased that STS kit. I used to be with the crew up there at ECS. May be able to plan something out if you guys need a few tunes I can make a trip up to PC and use my buddies Dynojet 424xLC there.
Thread Starter
Pro
Joined: Aug 2008
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From: Colorado springs
If it's not a vacuum leak, I've seen it caused by a improperly tuned car where what happens is the short term fuel trims are elevated in deceleration and then when you come to a stop, the elevated values skew your commanded fuel values accordingly but when you get down to idling, they're not needed and that demand changes. Although the trims begin to respond, they don't do it quickly enough and the engine has a difficult time until they get lined out. The next scenario is commanded airflow. When idling, the PCM will make adjustments to achieve commanded idle RPM. The second you touch the gas, the short-term adjustments zero out. If you're driving and don't have the proper commanded airflow, it doesn't know where to put the throttle blade for a moment and starts making adjustments accordingly, but not quickly enough. It's part of the PID strategy. Proportional, Integral, Derivative and can be sped up but you can be opening Pandora's box if you get lost in the adjustments, which is often not difficult to do.
I do not know 100% what you're talking about, but from a logical standpoint this is exactly how the car is behaving. The tuner added some "air" to the table, and that causes the idle to hang intermittently. So when coming to a stop every once in a while, the car will chug like it's searching for idle, or it will hang at about 1K RPM. Sometimes it will hang then start falling. But it will always sort it's self out after a couple of seconds. It sounds like a vacuum leak when it does it.
I'd have no problem taking care of FI tuning for you. As long as everything is copacetic mechanically, no reason why I cannot have that thing idling properly for you!
I am in Bradenton FL, which depending on where in south GA it could be a long ride to me...
I also go up to Panama City and use a dyno in that area doing tuning at weekend shots. This seems to be closer to you bladeboy. I believe we (Bladeboy) had spoke originally when you had purchased that STS kit. I used to be with the crew up there at ECS. May be able to plan something out if you guys need a few tunes I can make a trip up to PC and use my buddies Dynojet 424xLC there.
I am in Bradenton FL, which depending on where in south GA it could be a long ride to me...
I also go up to Panama City and use a dyno in that area doing tuning at weekend shots. This seems to be closer to you bladeboy. I believe we (Bladeboy) had spoke originally when you had purchased that STS kit. I used to be with the crew up there at ECS. May be able to plan something out if you guys need a few tunes I can make a trip up to PC and use my buddies Dynojet 424xLC there.
Drifting
Joined: Nov 2012
Posts: 1,665
Likes: 17
From: Bradenton Florida
St. Jude Donor '13
I do not know 100% what you're talking about, but from a logical standpoint this is exactly how the car is behaving. The tuner added some "air" to the table, and that causes the idle to hang intermittently. So when coming to a stop every once in a while, the car will chug like it's searching for idle, or it will hang at about 1K RPM. Sometimes it will hang then start falling. But it will always sort it's self out after a couple of seconds. It sounds like a vacuum leak when it does it.
I would be very interested in this. I have another buddy that might want to get in on a tune or at least a pull as well. I'm not sure if I originally spoke to your or not, or if we did perhaps it wasn't about this specific tune. Regardless, I bet you could throw out a group run on the events and regional forum to make it more worth your time.
I would be very interested in this. I have another buddy that might want to get in on a tune or at least a pull as well. I'm not sure if I originally spoke to your or not, or if we did perhaps it wasn't about this specific tune. Regardless, I bet you could throw out a group run on the events and regional forum to make it more worth your time.
It is probably a combination of airflow, follower, cracker, etc. Possibly with some AFR tuning also. I would want to go back through the entire tune though, it's hard to "fix" what someone else has done. I'll be glad to come on up if I can set this up. I was thinking the weekend of Jan 19th.
I believe that you had purchased the STS kit through me when I was at ECS. It was a customer's kit that we had helped sell (I was Matt@ECS). Unless I have your forum name completely wrong, then disregard!
If we can get some interest I'll set this up...
Figure I can do Forced Induction Dyno Tunes if I travel up there for $599 all-inclusive (Includes dyno time/printouts) and if we are doing multiple boost levels it might be a few bucks more. I'll work on pricing for bolt-ons and N/A combinations too...
Pro
Joined: Jun 2007
Posts: 501
Likes: 3
From: Valdosta GA
It is probably a combination of airflow, follower, cracker, etc. Possibly with some AFR tuning also. I would want to go back through the entire tune though, it's hard to "fix" what someone else has done. I'll be glad to come on up if I can set this up. I was thinking the weekend of Jan 19th.
I believe that you had purchased the STS kit through me when I was at ECS. It was a customer's kit that we had helped sell (I was Matt@ECS). Unless I have your forum name completely wrong, then disregard!
If we can get some interest I'll set this up...
Figure I can do Forced Induction Dyno Tunes if I travel up there for $599 all-inclusive (Includes dyno time/printouts) and if we are doing multiple boost levels it might be a few bucks more. I'll work on pricing for bolt-ons and N/A combinations too...
I believe that you had purchased the STS kit through me when I was at ECS. It was a customer's kit that we had helped sell (I was Matt@ECS). Unless I have your forum name completely wrong, then disregard!
If we can get some interest I'll set this up...
Figure I can do Forced Induction Dyno Tunes if I travel up there for $599 all-inclusive (Includes dyno time/printouts) and if we are doing multiple boost levels it might be a few bucks more. I'll work on pricing for bolt-ons and N/A combinations too...
Where is the dyno located you are talking about? I may be interested!
Edited:
Just saw you stated Panama City. That might work for me actually it is not to far away. I'll PM you need more info.
Last edited by mobius; Jan 3, 2013 at 07:36 PM.
Former Vendor
Joined: Oct 2007
Posts: 2,032
Likes: 6
From: longview tx
Idle can be fun sometimes. With certain cams it could take a couple days to get it perfect. If you dont have a cam in the car, well, lol then it shouldn't even have issues with a 3 pull and out tune...... Like stated. If it was 3 pulls and out the door tune then the idle was not adjusted properly on a cammed car. To get it right you would need to drop it off and have a tuner do it right. Buzz up to ECS( not close but not far) and they can get it lined out for you im sure!
Thread Starter
Pro
Joined: Aug 2008
Posts: 574
Likes: 5
From: Colorado springs
It is probably a combination of airflow, follower, cracker, etc. Possibly with some AFR tuning also. I would want to go back through the entire tune though, it's hard to "fix" what someone else has done. I'll be glad to come on up if I can set this up. I was thinking the weekend of Jan 19th.
I believe that you had purchased the STS kit through me when I was at ECS. It was a customer's kit that we had helped sell (I was Matt@ECS). Unless I have your forum name completely wrong, then disregard!
If we can get some interest I'll set this up...
Figure I can do Forced Induction Dyno Tunes if I travel up there for $599 all-inclusive (Includes dyno time/printouts) and if we are doing multiple boost levels it might be a few bucks more. I'll work on pricing for bolt-ons and N/A combinations too...
I believe that you had purchased the STS kit through me when I was at ECS. It was a customer's kit that we had helped sell (I was Matt@ECS). Unless I have your forum name completely wrong, then disregard!
If we can get some interest I'll set this up...
Figure I can do Forced Induction Dyno Tunes if I travel up there for $599 all-inclusive (Includes dyno time/printouts) and if we are doing multiple boost levels it might be a few bucks more. I'll work on pricing for bolt-ons and N/A combinations too...
Matt, well why didn't you say that was you! LOL I honestly didn't make the correlation or know you left ECS. Yeah that was me earlier this year.
I would have to hold tentative to the weekend of the 19th, I have a family member who will be passing soon. So something that soon might not work. If you are deciding to make the trip any ways for the other member then I'll keep you updated.
If you know how to get this kit up to 7Lbs then I'll make it worth while for me as well, thing won't push past 5.
Pro
Joined: Jun 2007
Posts: 501
Likes: 3
From: Valdosta GA
I am good with pushing this out a couple weekends if you guys want? I wouldnt mind switching intercoolers on the car before I get it tuned so that would give me time to get it done. LMK. Matt I'll try to give you a call tomorrow to talk about my setup and tuning some more.
Thanks
Jason
Thanks
Jason
Drifting
Joined: Nov 2012
Posts: 1,665
Likes: 17
From: Bradenton Florida
St. Jude Donor '13
Definitely guys let me know.. I may still make the trip on the 19th because I have a client up there with a '12 camaro we're trying to push into the deep 10's and a few other cars to do.
I'll look at my schedule too might be able to also do top of February.. End of February into March is terrible because we have so many events going on then..
I'll look at my schedule too might be able to also do top of February.. End of February into March is terrible because we have so many events going on then..
