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Discussion Starter #1
Does anyone have tips on getting id1000s to idle on a d15b7 jrsc? Trying to just start it and it's running rich. Around 7s afr. It will try to idle for a few seconds or surge to 3000rpm and die. Using a Hamotorsports crome type p28, p06 map vtec disabled with Honda Tuning Suite. No CEL. I have set the deadtimes to id1000 40psi.
 

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93 Civic HB SI
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Have you modified any of your IAT, ECT, cranking and TPS fuel corrections yet? You may need to pull a bunch of fuel depending on what these default values are.

Good rule of thumb, adjust these fuel modifiers FIRST to get the car to idle, BEFORE pulling fuel from the map.

Remember, the fuel/ignition tables are rather static (unless purposely modified), and is the basis of what the modifiers use to correct from. The modifiers are dynamic, and are constantly changing along a defined interpolated scale based on what the modifier is looking at (ECT, IAT, etc.)

You want to adjust the things that change dynamically (the modifiers) BEFORE changing things that are rather static in nature (the fuel/ignition tables). Otherwise, you'll only ever be able to tune the fuel map to ONE modifier range. The modifiers never go away, and will constantly correct the map depending on ECT, IAT, etc. sensor feedback. You have to get these right first.

I know you've heard this said in tuning circles before "The OE map is a good place to start." The tuning software will only get you so far when you tell it what size injectors you've installed. The above listed modifiers need to be tweaked to reign in fuel control. You should be able to at least get the car running with decent AFR by only adjusting these modifiers first.

Once you get the car to run decent with these, your technically running the car with the overall fuel map as Honda intended. From HERE, you can go to town datalogging and using AFR input and lambda overlay to fine tune any areas on the overall map that end up being unique to your injector operation, as well as adding the columns for fuel and ignition in boost.
 

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I have not touched those modifier valves. Thanks for explaining it to me. Since I am running rich right now, I should log the conditions it is in (eg: IAT, ect...etc) when trying to start and lower the values in their fuel settings per condition (eg: 70f ect)?
 

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I have not touched those modifier valves. Thanks for explaining it to me. Since I am running rich right now, I should log the conditions it is in (eg: IAT, ect...etc) when trying to start and lower the values in their fuel settings per condition (eg: 70f ect)?
Yes. But since you say your wideband is hitting 7:1, I would honestly just go ahead and pull a bunch of fuel out of each of those modifiers, and see what happens. I would shoot for trying to pull things up into the 11's or 12's by just manually tweaking, THEN datalog to try and get idle closer to 14's and 15's.

I would start with ECT correction. Pull a bunch of fuel from each range, then when you get up to operating temp, tweak on that range the most to get AFRs in control. Use that correction value as a means to determine how you might need to interpolate fuel across the lower ECT ranges to maintain fuel control.

Remember, lower ECTs need more fuel in comparison to operating temp to maintain drivability.
 

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ECT should be the dominant controller of fuel trim up until the engine begins to enter the operating temperature zones.

IAT's become critical modifiers when ambient air temps are either extremely cold (need to fatten fuel up for very cold air induction), or become hot enough to begin negatively affecting cylinder heat soak beyond the capabilities of an intercooling device, which can directly affect the pre-ignition qualities of the fuel/air charge.

ECTs are pretty much the temperature parameter that a tuner can use and know will hold relatively steady (as long as cooling system is working properly and components are in good working order). This temperature is a good reflection of overall engine temperature status, and can be used to make good assumptions of the temperatures of engine hard internal components.

You can bet that a significant increase in coolant temp above typical thermostat regulation temp means that the metals inside the engine around combustion exposed surfaces are getting HOT. The cooling system should manage the heat dissipation of these components within reason, therefore feedback from this sensor is critical to determine base fuel/ignition settings. High IATs can affect the ECT to a point, but not as much as directly affecting the overall immediate temperature of the cylinder fuel/air charge.

IAT temps should be looked at as "in addition to ECT" corrections in most cases. Under boost, the compressed air is HOT, and is only adding heat to the intake charge, which affects in cylinder temps as well as increasing the chance of knocking. That's why there is typically an IAT ignition correction modifier area as well, so you can pull timing as well as add fuel when you begin to see abnormally high IATs. Just another level of fuel/ignition control.

ECTs should be primary corrections, IATs are more of a secondary correction, since IATs behave independently of ECTs due to many external factors not directly related to things that govern ECTs.
 
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