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ECMlink Help needed understanding strange results when trying to tune car. Logs attached

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And another alternator is going to be in the works as money allows. I am looking at the 90 amp galant as a replacement when I do get one. From what I have seen on other threads on here it is a direct bolt up. I noticed in my logs when the vehicle is first started its putting out around 14 at idle. As the car starts to get close to 200 degrees the output slowly start going down till it gets to about 13v. It does go up slightly with revs but I still think it should be a little higher than what it is putting out.
 
It's too lean. Add global to achieve 100 VE in cells at 5-6000rpms while targeting your AFR's.

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I did not read everything but in my experience most important things to check at the beginning is zero air leaks and that the throttle body is set up exactly correctly and you maf and o2 sensor are working properly. After this setting up correct injector settings to dsm link should give stable afr on idle when engine has warmed. Most of time any of my issues has been airleaks even on the injector seals. There is no point to tune if there is any air leaks. Pressuring the system after turbo and spraying soapy water to any possible leaking point including throttle body shaft seals bis screw and injectors is what i do.
 
It's too lean. Add global to achieve 100 VE in cells at 5-6000rpms while targeting your AFR's.

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I just want to make sure I understand this right. Your telling me to increase the global dead time under the fuel tab and use the track VE table and see when those highlighted sections of the VE table are 100. Or are you telling me to increase the hight lighted sections for the VE table to 100?
 
I just want to make sure I understand this right. Your telling me to increase the global dead time under the fuel tab and use the track VE table and see when those highlighted sections of the VE table are 100. Or are you telling me to increase the hight lighted sections for the VE table to 100?
Yes. Set the highlighted ve cells to 100. Do a wot pull to see afr’s. If you need more fuel, increase global, not deadtime, to get to your target afrs. Deadtime adjustment is for idle and cruise, no affect during wot.
 
If you need more fuel, increase global, not deadtime, to get to your target afrs.

Are you sure? Increasing the fuel global says I have bigger injectors and you wind up with shorter injector pulse widths which would actually make the car leaner since the injector didn't change.

Changes to injector deadtime do effect WOT but since at WOT the pulse widths are large compared to idle the percentage of difference is much smaller and the impact is less.
 
Are you sure? Increasing the fuel global says I have bigger injectors and you wind up with shorter injector pulse widths which would actually make the car leaner since the injector didn't change.

Changes to injector deadtime do effect WOT but since at WOT the pulse widths are large compared to idle the percentage of difference is much smaller and the impact is less.
Jump to 5:00 in the video. I haven’t seen deadtime effect wot afr’s much at all. Increasing global will add fuel. The bigger the injector, global is more negative. How else would you add more global? More negative? That doesn’t make sense.

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Ok I did some watching of Scott Lairds YT videos and think I am finally starting to wrap my head somewhat around this.

Watch this video at 5:14-7:28
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So after watching that section of the video, going off the portion of my log that TK's9d2TSi posted, my wideband factor was 22.5% meaning I was that much lean at that point of the log. Since my cells are already set around 99 in the affected cells, that means I would have to adjust them to 121.5 to get it to not be lean. Since it seems most people don't like to adjust them higher than 100, I should probably do the calculations he showed in the video to adjust my injector size, which according to my calculations I did last night would bring me to around 1,000 cc injectors instead of the 1,230 or whatever is in there now.

Yes raising global will increase fuel because it is a negative number. Since mine is around -69.5 increasing it would take it closer to 0 which thus would be increasing the fuel it puts out.
 
] posted, my wideband factor was 22.5% meaning I was that much lean at that point of the log. Since my cells are already set around 99 in the affected cells, that means I would have to adjust them to 121.5 to get it to not be lean. Since it seems most people don't like to adjust them higher than 100, I should probably do the calculations he showed in the video to adjust my injector size, which according to my calculations I did last night would bring me to around 1,000 cc injectors instead of the 1,230 or whatever is in there now.
#1, does your wideband gauge perfectly match what gets logged in link?

#2, if it does I would raise the base fuel pressure rather than changing the injector global
 
Jump to 5:00 in the video. I haven’t seen deadtime effect wot afr’s much at all. Increasing global will add fuel. The bigger the injector, global is more negative. How else would you add more global? More negative? That doesn’t make sense.

I looked at 5:00 in the video, it was about deadtime and said what I said. If you were assuming that I was suggesting using deadtime here, I wasn't. Just pointing out that deadtime is always a factor but it impact is in proportion to the total IPW. So it's big at small IPW's and small at big ones.

Where my brainfart was last night was, was in the what you meant by "increase global". TurboSpider understood you and added a positive number to a negative number there by getting a smaller negative number. It's common to people to forget about the sign (since they are almost always negative here) and just talk about the magnitude, which is what I thought you meant in my comment.

My apologies for misunderstanding you.
 
Pretty sure it matches but I can double check it again.

Why would raising the fuel pressure be better then increasing dead time? Not saying you not right, just trying to understand why it would be better as I am learning. I believe mine is set at 42.6 or whatever is stock for 2g don't remember the number off top of my head.

Also are you talking about changing it in link under fuel settings to a higher number or actually physically changing it at regulator or both?
 
Physically changing it at the regulator. Stock is 43.5 fyi. Also, most regulators aren't super accurate and need this type of calibration.

If your injectors are 1200s, then you shouldn't be entering them in as 1000s. Something is off. When using SD we use wot to calibrate the fuel system. Your VE should be 100, your injectors set up for 1200cc, and adjust fuel pressure until the 100ve cells are lining up with the targeted afr.

Then go back and retune cruise and idle.
 
Ok I will bump the regulator up to maybe 45psi, leave the fuel pressure in ECM link set at the stock 43.5, reset the fuel trims and do a small pull and see what I get
 
I looked at 5:00 in the video, it was about deadtime and said what I said. If you were assuming that I was suggesting using deadtime here, I wasn't. Just pointing out that deadtime is always a factor but it impact is in proportion to the total IPW. So it's big at small IPW's and small at big ones.

Where my brainfart was last night was, was in the what you meant by "increase global". TurboSpider understood you and added a positive number to a negative number there by getting a smaller negative number. It's common to people to forget about the sign (since they are almost always negative here) and just talk about the magnitude, which is what I thought you meant in my comment.

My apologies for misunderstanding you.
All good Steve and no need to apologize. Hope my response didn’t come off in a bad way as I’d never speak to you that way. We all have brain farts LOL.
 
Ok I will bump the regulator up to maybe 45psi, leave the fuel pressure in ECM link set at the stock 43.5, reset the fuel trims and do a small pull and see what I get
Another fyi, all changing the fuel pressure in link does is change the injector global calculation.

If your wideband is logging accurately, and you really DO need to add 22% at the 100ve cells, then you're probably going to have to bump the base fuel pressure up to around "50"psi or so.
 
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If your injectors are 1200s, then you shouldn't be entering them in as 1000s.
I disagree. I’ve tuned 4 different size injectors and three of them (550 1000 & 1650) calculated to about 10-20% lower once tune was dialed in. Here is my log from March with 1650's. All said and done, they calculate to 1400's.
 

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Ok, I think I understand... so if we increase it at regulator while leaving it at what its set in link it will fool the system into adding more fuel without it changing the dead times and possibly negating the changes we made at the regulator.

Prettys sure the wideband is correct. It was showing around 14.7 at idle like it should in some of my logs but I will double check the gauge matches what ecm link is seeing. Ok I will try 50 psi at the regulator and reset trims and do a pull and post the results.
 
I disagree. I’ve tuned 4 different size injectors and three of them (550 1000 & 1650) calculated to about 10-20% lower once tune was dialed in.
Did you double check the fuel pressure with an extra gauge? Did you log fuel pressure to make sure it was rising 1:1? Are you positive that your airflow was dialed in right? Were the injectors cleaned/tested?

There's a lot of variables to a tune, but if the manufacturer says they are 1200s, that's what I'm entering in. I'm going to say that is a constant. You're right to suspect that they might not be flowing 1200cc, maybe they are dirty or just faulty. It definitely happens and quite often at that (But so do fuel pressure gauge innacuracies).

However, if you have the fuel pump to do it, I would rather bump the pressure and enter the manufacturer rating of the injector than enter in a smaller injector for global. What we know for sure is, something in the fuel system isn't flowing what it's supposed to be/says it is/is rated at.
 
so if we increase it at regulator while leaving it at what its set in link it will fool the system into adding more fuel without it changing the dead times and possibly negating the changes we made at the regulator.

Adjusting the base fuel pressure actually changes the flow rate of the injectors. If for some reason your fuel pressure gauge is off and reading high, your injectors would be delivering less fuel than the ECU is expecting based on the numbers you told it.

Stealing from RC, here's the relationship between injector flow rate (size) vs base fuel pressure changes.

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Did you double check the fuel pressure with an extra gauge? Did you log fuel pressure to make sure it was rising 1:1? Are you positive that your airflow was dialed in right? Were the injectors cleaned/tested?

There's a lot of variables to a tune, but if the manufacturer says they are 1200s, that's what I'm entering in. I'm going to say that is a constant. You're right to suspect that they might not be flowing 1200cc, maybe they are dirty or just faulty. It definitely happens and quite often at that (But so do fuel pressure gauge innacuracies).

However, if you have the fuel pump to do it, I would rather bump the pressure and enter the manufacturer rating of the injector than enter in a smaller injector for global. What we know for sure is, something in the fuel system isn't flowing what it's supposed to be/says it is/is rated at.

Increasing bfp or raising global will basically get the same results and yes there are variables when it comes to tuning including how one engine flows different from the next. If you go to link's page injector data page, you'll see the global & deadtimes for the popular dsm injectors and when you run it through the calculator, they all turn out to be smaller sized injectors. I've seen several car's dyno tuned and I never see the tuner making a pull, then go under the hood to turn up the fp.

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If you go to link's page injector data page, you'll see the global & deadtimes for the popular dsm injectors and when you run it through the calculator, they all turn out to be smaller sized injectors. I've seen several car's dyno tuned and I never see the tuner making a pull, then go under the hood to turn up the fp.
You're using 42psi base fuel pressure instead of 43.5.

And ok, so every dyno tuner chooses to assume that the manufacturer is wrong about injector sizes and chooses to believe the mechanical fuel pressure gauge instead. 2-5psi off is fairly common and 4.3psi fuel pressure = a 10% difference in flow rate.

Two ways to skin this cat. Both will work, but no way to know which one is correct without spending money on some testing. If you're close to maxing out the idcs then definitely raise fuel pressure. OP has a re-wired 255hp so that would be my choice in this instance.
 
You're using 42psi base fuel pressure instead of 43.5.

Even with 43.5 bfp, global is 850 for 1000’s. I agree, more than one way to skin a cat. I’ve learned this way and it works for me, and I’m sure same applies to you. Curious what the pro’s do.
 
Not saying anyone is right or wrong or agreeing or disagreeing, however I will say in my experience the only time I’ve seen base pressure increased is when trying to stretch injectors beyond what they’re capable of.
Or to combat knock
 
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