FIC 1650cc injectors idling rich on 93 octane
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I'm just repeating it for the benefit of those who are a bit slow on the uptake.
What's the point in looking for new problems to fix when you don't want to try to fix the already obvious problems.
What's the point in looking for new problems to fix when you don't want to try to fix the already obvious problems.
If the primary pump is on the stock wiring (not hardwired) fuel pressure at idle is not the issue (for a rich condition anyways). If it's hardwired, that's a different story.
As far as the PW linearization table superceding MIN IPW patch. They are two different things. One is PW adder based on commanded pulse width to, literally, make the injector's flow linear at low pulse width. The other (MIN IPW patch) allows you to alter the how low of an IPW the ECU can command. At least that's how I understand it.
FWIW, my car idles fine on pump gas without messing with the IPW linearization.
As far as the PW linearization table superceding MIN IPW patch. They are two different things. One is PW adder based on commanded pulse width to, literally, make the injector's flow linear at low pulse width. The other (MIN IPW patch) allows you to alter the how low of an IPW the ECU can command. At least that's how I understand it.
FWIW, my car idles fine on pump gas without messing with the IPW linearization.
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From: wisconsin
Read post 218
https://www.evolutionm.net/forums/ec...um-ipw-15.html
As for Fred well it's Fred. People increase their fuel pressure all the time to get more flow out of the injectors. It's not a bad/wrong thing to do, it's just with large injectors it becomes hard to get the air fuel lean at idle. Low boost or N/A cars sometimes run 60-70 psi base pressure.
https://www.evolutionm.net/forums/ec...um-ipw-15.html
As for Fred well it's Fred. People increase their fuel pressure all the time to get more flow out of the injectors. It's not a bad/wrong thing to do, it's just with large injectors it becomes hard to get the air fuel lean at idle. Low boost or N/A cars sometimes run 60-70 psi base pressure.
Read post 218
https://www.evolutionm.net/forums/ec...um-ipw-15.html
As for Fred well it's Fred. People increase their fuel pressure all the time to get more flow out of the injectors. It's not a bad/wrong thing to do, it's just with large injectors it becomes hard to get the air fuel lean at idle. Low boost or N/A cars sometimes run 60-70 psi base pressure.
https://www.evolutionm.net/forums/ec...um-ipw-15.html
As for Fred well it's Fred. People increase their fuel pressure all the time to get more flow out of the injectors. It's not a bad/wrong thing to do, it's just with large injectors it becomes hard to get the air fuel lean at idle. Low boost or N/A cars sometimes run 60-70 psi base pressure.
I agree, that the IPW linearization does more. But I don't think it replaces the min IPW patch. Because if MIN IPW is 1.5ms, that's all you get, even if you need .8ms...
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218 says the min IPW patch only helps at idle, where as the IPW linearization helps at through the entire range of pulse where the injector is non-linear.
I agree, that the IPW linearization does more. But I don't think it replaces the min IPW patch. Because if MIN IPW is 1.5ms, that's all you get, even if you need .8ms...
I agree, that the IPW linearization does more. But I don't think it replaces the min IPW patch. Because if MIN IPW is 1.5ms, that's all you get, even if you need .8ms...
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From: wisconsin
In post 216 Fred says this;
Its probably not what you want to hear, but the minimum IPW patch is totally unnecessary if the injectors are tuned properly. In fact the minumum IPW is a complete kluge for when we had no idea about partial opening injector response. See my thread on 2150 settings.
Its probably not what you want to hear, but the minimum IPW patch is totally unnecessary if the injectors are tuned properly. In fact the minumum IPW is a complete kluge for when we had no idea about partial opening injector response. See my thread on 2150 settings.
Ok, I think I see what he means now.
By tuning the linearization table, you don't need to lower the min IPW because you are able to get fueling in line with commanded pulse width.
By tuning the linearization table, you don't need to lower the min IPW because you are able to get fueling in line with commanded pulse width.
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From: Chicago, IL
You should see 35-37 psi at idle with the vacuum line connected depending on how big your cams are. Once you start getting over 39-40 at idle it will be harder to tune. i drill the siphon on double Pumpers no matter what the fuel pressure at idle is because it helps with the rich afr when the second pump kicks on.
No it will not require a full retune, just idle and part throttle areas of the map. If you drill the siphon then you may need to touch up afr's up top also.
One thing that can help also is to turn down the timing in the rich idle areas. This will load the motor down some at idle. It in turn will require more fuel to idle. Bump it down around 5-7 degrees.
This is a lot of screwing around so treat your tuner well and he will get it ciphered out I'm sure.
Mr Freds post has settings that are very close, so start with his latencys and linearization settings.
No it will not require a full retune, just idle and part throttle areas of the map. If you drill the siphon then you may need to touch up afr's up top also.
One thing that can help also is to turn down the timing in the rich idle areas. This will load the motor down some at idle. It in turn will require more fuel to idle. Bump it down around 5-7 degrees.
This is a lot of screwing around so treat your tuner well and he will get it ciphered out I'm sure.
Mr Freds post has settings that are very close, so start with his latencys and linearization settings.
I checked the fuel pressure at idle today. It was around 38 psi.
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From: in a garage
Yes, 5 PSI too high.
Check it again but this time turn on all your lights and fans....report back.
Also take a note of the manifold vac .
It's the difference between manifold vac and gauge pressure which is the base pressure which should be constant (3 bar) and NEVER deviate.
Check it again but this time turn on all your lights and fans....report back.
Also take a note of the manifold vac .
It's the difference between manifold vac and gauge pressure which is the base pressure which should be constant (3 bar) and NEVER deviate.
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Or maybe I just skimmed through this thread and you guys arent talking about what i think you are.
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From: wisconsin
38psi That's about what I expected it's usually 2-3 pounds higher than stock pump. No big deal if you drill the siphon I bet it drops 2-3 psi. This will bring you up .5 afr not a lot. If you tuner does the mods in the 1650 thread, linearization table. The min IPW too just set it around .900, then tune the afr around 13.5-14.5 it should start to run poorly any leaner due to injectiors response time. Back the afr down a .5 point and it's smooth as a baby's bottom. Keep you idle timing around 12 degrees.
Originally Posted by Biggiesacks
I think you guys are confusing two different things. The Linearization tables will allow the ecu to generate the correct pulse width for your injectors in their non linear region, but if that correct pulse width is below the Min Injector pulse width setting then the ecu cannot send a pulse width that small. Which is why you would need to lower Min IPW if you happen to fall in that range.
Or maybe I just skimmed through this thread and you guys arent talking about what i think you are.
Or maybe I just skimmed through this thread and you guys arent talking about what i think you are.
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From: Streets of willow
I think you guys are confusing two different things. The Linearization tables will allow the ecu to generate the correct pulse width for your injectors in their non linear region, but if that correct pulse width is below the Min Injector pulse width setting then the ecu cannot send a pulse width that small. Which is why you would need to lower Min IPW if you happen to fall in that range.
Or maybe I just skimmed through this thread and you guys arent talking about what i think you are.
Or maybe I just skimmed through this thread and you guys arent talking about what i think you are.
the non linear region.