Cant get idle puslewidth down and stable? Well versed guys inside
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TECH Junkie
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From: Glen Burnie, Md
Cant get idle puslewidth down and stable? Well versed guys inside Maybe Im missing something here, but I cant get the idle pulsewidth to even stay on the minimum. Lowest I can get it to go to is 1.0ms or so and even then it jump erratically between that and 1.9. Was 1.3min from factory of course and jumping to 2.6, so something is intermittently doubling it.
220# injs, lots fuel need to get the low end of this map cleaned up, killing the oil right now. Can email tune file or log
220# injs, lots fuel need to get the low end of this map cleaned up, killing the oil right now. Can email tune file or log
If your idle MAP is jumpy, from the cam be lumpy, your
injector shot will simply follow. Scan tool frame rate may
not follow all that well, may decimate the data. But if
you see unsteady idle MAP then this may be the deal.
injector shot will simply follow. Scan tool frame rate may
not follow all that well, may decimate the data. But if
you see unsteady idle MAP then this may be the deal.
Thread Starter
TECH Junkie
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From: Glen Burnie, Md
Idle kPa stable, little cam, its a turbo car. doesnt jump around with different data points, its dead on one value or another, one value or double that value. Something in ECM is causing that, theres no table that wouldnt interpolate and come up with in between numbers.
Maybe Im missing something here, but I cant get the idle pulsewidth to even stay on the minimum. Lowest I can get it to go to is 1.0ms or so and even then it jump erratically between that and 1.9. Was 1.3min from factory of course and jumping to 2.6, so something is intermittently doubling it.
220# injs, lots fuel need to get the low end of this map cleaned up, killing the oil right now. Can email tune file or log
220# injs, lots fuel need to get the low end of this map cleaned up, killing the oil right now. Can email tune file or log
You're pretty much at the limit of control of the injectors. You can't really run em much lower than 1 ms. I've got em to run in the high .8 to .9 range, but that's about it.
I wold bet that it's pegging your fuel trims. Then it re-zeros, that's when you get the jump from 1 ms up to 2 ms, and then it starts over.
As suggested, how bout a log and tune?
I wold bet that it's pegging your fuel trims. Then it re-zeros, that's when you get the jump from 1 ms up to 2 ms, and then it starts over.
As suggested, how bout a log and tune?
If you can't get it low enough, you might have to idle it higher or think about putting in a vacuum biased fuel pressure regulator. At least you could kill the pressure down low and command a higher pulse width for the idle stuff.
How much power are you making with this setup? Those injectors could make a conservative 2500hp!!!!
How much power are you making with this setup? Those injectors could make a conservative 2500hp!!!!
Only problem with that is at low pressure those big injectors spit. It ain't purdy. I would almost suggest smaller injectors, and a boost referenced reg. Although I have no idea what power level we're dealing with.
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TECH Junkie
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From: Glen Burnie, Md
Reduced base pressure to make it easier on the pumps, would be roughly 150% duty cycle at same power level with 100#s in it still, and at times have a few hundred more hp that needs to be fed. Theres no in between injector for a stock computer.
Ed if i could get them to stay steady at 1.0ms id be fine I think, they just wont stay there. Completely erratic 1.0/1.9/1.0 - open loop, no fuel trims
Last edited by GrannySShifting; Sep 23, 2010 at 07:21 PM.
Dude, you've got it in 3 bar, but you've still got the MAF functional. I've only got a few to work right with both.
Anyways, send me an email. edcmat-l1@msn.com. We'll take it there.
Anyways, send me an email. edcmat-l1@msn.com. We'll take it there.
Isnt the only way to get teh MAF to work with a 2 or 3 bar tune is for out-of-boost driving then as soon as the MAF is pegged it defaults to the extended VE table and wont go back to using the maf till the key is turned back off?
Considering 120lb injectors would suffice all the way up to 850-900 rwhp with E85 on a T76 which is where that turbo will max out, yes those injectors are definitely overkill.
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TECH Junkie
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From: Glen Burnie, Md
it throws MAF fail immediately on startup, so dont think its functioning?
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TECH Junkie
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From: Glen Burnie, Md
Dude, you've got it in 3 bar, . edcmat-l1@msn.com. We'll take it there.
considering there are no 120# inj you can run on a stock computer like i run, and I made 799 thru a glide on my mustang dyno with a new NTK sensor and the measured data I gave you to arrive at that a/f, with 15 volts at the pump, on the next size down high impedance injector (ID1000s) these arent guesses. Ive done it, used up all the ID1000s could give, and need to feed a few hundred more hp at A) less volts B) less base pressure. Only one bigger high impedance inj that Im aware of, and its the 220s
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TECH Junkie
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From: Glen Burnie, Md
I fully believe the ID1000s aren't enough, those are only ~95lb injectors so I am not sure why are are arguing. There are plenty of other options in between those two injectors you listed when you run a driver box on your factory PCM like I am doing to get you where you need to be without riding minimum pulsewidths and having muddy idle/decel fueling. The jump from a 95lb injector like the ID1000s to the 220s is more than double and you are going to have problems with them being as large as they are. A set of 120lb injectors are going to flow damn near 30% more than those ID1000s getting you to where you want to be and I can tell you from experience they idle great and clean at stoich on a 347ci setup even.
Well... I guess you're screwed if you are going to limit yourself like that but Racetronix makes a nice plug/play harness for the versafueler that takes 5 minutes to install.
So you are using a 220 # high inpedence injector that you want to run at 1ms pulsewidth!!!!!
I don't let 60lbers go below 3ms. Makes for a very unstable idle because of the injectors not even turning on sometimes below that.
Like was stated, if you need that much fuel, you are going to need the driver box and get some low impedance injectors.
What you are trying to do is pretty much like going to prom with your sister, yeah, your there, but it just ain't right!!!
I don't let 60lbers go below 3ms. Makes for a very unstable idle because of the injectors not even turning on sometimes below that.
Like was stated, if you need that much fuel, you are going to need the driver box and get some low impedance injectors.
What you are trying to do is pretty much like going to prom with your sister, yeah, your there, but it just ain't right!!!
So you are using a 220 # high inpedence injector that you want to run at 1ms pulsewidth!!!!!
I don't let 60lbers go below 3ms. Makes for a very unstable idle because of the injectors not even turning on sometimes below that.
Like was stated, if you need that much fuel, you are going to need the driver box and get some low impedance injectors.
What you are trying to do is pretty much like going to prom with your sister, yeah, your there, but it just ain't right!!!
I don't let 60lbers go below 3ms. Makes for a very unstable idle because of the injectors not even turning on sometimes below that.
Like was stated, if you need that much fuel, you are going to need the driver box and get some low impedance injectors.
What you are trying to do is pretty much like going to prom with your sister, yeah, your there, but it just ain't right!!!
60's are easily stable down to 1.1mS. At 3mS, you are going to have a FAT idle with 60's!