What fuel compensation table effects cold starts?

s300 and SManager software questions & answers
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G. Wiffington
Posts: 67
Joined: Tue Nov 21, 2017 12:24 pm

What fuel compensation table effects cold starts?

Post by G. Wiffington »

So I usually am able to figure out my issues from looking on the forum here but, I was somewhat confused about which fuel compensation table directly effects the fuel during a cold start or during the cranking period when starting?

I do not have my calibration or datalog to share because I am at work right now.

1993 Honda Accord
Euro-R H22A
s300

The issue I was having was that I have been tuning my car in temperatures from 40 degrees Fahrenheit to about 65 degrees but, last weekend the weather in Maryland, USA was about 80-85 degrees outside which caused my car to give way too much fuel during cranking & it would not start. This is the first time I have started my car during warmer weather & the first time tuning during warmer weather since I got my s330 installed during Winter time. Also, this is the first time I have not been able to start my car on first try, which is why I was concerned. I have heard tuning in different air temperatures can cause some issues but I thought it was weird I was unable to start my car.

I have never had any trouble starting my car during the colder months but as soon as it got really hot outside my car was giving way too much fuel during cranking.

I tried subtracting fuel in the "Cranking Fuel Trim" in the Fuel Trim Parameters & eventually got it to start. But, I had to give some throttle for a second or two to get the car to idle.

Which table under Fuel Compensation effects the cranking fuel compensation?

I read in another thread that the "Water temperature fuel compensation cranking" is what controls the compensation for cranking. Is this the table that needs to be adjusted according to the temp?

I would have thought it would be the Intake Air Temperature that effects the cranking fuel compensation due to the temperature of the air. Is the water temperature where the cranking compensation is effected?

Sorry I just wanted to understand since the s300 Programmable ECU Guide does not have too much description about this.
crluver123
Posts: 155
Joined: Tue Oct 10, 2006 10:13 pm

Re: What fuel compensation table effects cold starts?

Post by crluver123 »

cranking fuel, fuel rate of decay, air temp, and coolant temp compensations all affect cold start
G. Wiffington
Posts: 67
Joined: Tue Nov 21, 2017 12:24 pm

Re: What fuel compensation table effects cold starts?

Post by G. Wiffington »

Alright thanks. But, is there a table that reflects more on the air temperature outside?

My tune has been pretty good during the colder weather but as soon as it got hot outside my cranking fuel just seemed over-rich. I was just curious as to what I could change in the parameters that would reflect on the temperature outside. That is why I was thinking it had something to do with the water temperature (ECT).

I think the thread I was looking at about "Water temperature fuel compensation cranking" was for FlashPro but I have s300.
G. Wiffington
Posts: 67
Joined: Tue Nov 21, 2017 12:24 pm

Re: What fuel compensation table effects cold starts?

Post by G. Wiffington »

So I did some more research through the ECU Programmable Guide & found some good info.

Theory of Air Temperature Compensation, is a pretty good section under the Fuel Compensation Parameters. In that section I was reading about the formula for "Air Density" which is very helpful.

With following the equation of how to configure the "fuel correction" I noticed that my correction values that were already input into my parameters were way too high for my engine setup. Using the equation I was able to take my correction values down per each temperature in the Air Intake Temperature Parameters for the different "Loads".

I am still playing with the numbers for the fuel correction but for now it seems that lowering the correction percentage for 60s-150s degrees has helped my car start better during the warmer temperature outside.
G. Wiffington
Posts: 67
Joined: Tue Nov 21, 2017 12:24 pm

Re: What fuel compensation table effects cold starts?

Post by G. Wiffington »

Here is a upload of my last saved datalog & map from 05.05.2018
Attachments
05.02.2018 82 degrees out.s3d
(5.55 MiB) Downloaded 135 times
G. Wiffington
Posts: 67
Joined: Tue Nov 21, 2017 12:24 pm

Re: What fuel compensation table effects cold starts?

Post by G. Wiffington »

Added
Attachments
05.02.2018 82 degrees out.skl
(44.85 KiB) Downloaded 137 times
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