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ECMlink MAFComp Sliders High

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Mham2k

15+ Year Contributor
306
57
Feb 8, 2008
Dallas, Texas
Can someone help me out, I took my surge tank out and now am just running from the intank pump only. Pump is a Aeromotive 340.

Why are my MAF Sliders so freaking high, they were max of 20% before.
See the attached log
 

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  • log.2018.11.24-01.elg
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You just need to dial in your MAF with the sliders. Your settings are kind of crazy right now and your BoostEst and AFRs show it.

I understand that, my question is why my MAF sliders are going so high.

Before when I tuned I maxed around 20% on the MAF sliders to get my wbfactor hovering around 0 up to 2000hz.

Now I'm close to 50% and it wants me to add more. If I keep going I will max out the chart. Trying to understand why I have to push them so high now.

I cant tune my car to 20psi the way it's going.
 
The highest MAF reading I'm seeing is about 1100Hz. You are adjusting 1200+ for no reason IMO. Even your BoostEst and actual boost is way off because of the added MAF signal. You need to zero things back out and add global fuel if need be. Adjust and dial in both your MAF and injectors.
 
The highest MAF reading I'm seeing is about 1100Hz. You are adjusting 1200+ for no reason IMO. Even your BoostEst and actual boost is way off because of the added MAF signal. You need to zero things back out and add global fuel if need be. Adjust and dial in both your MAF and injectors.

So your saying increasing global fuel will decrease the amount of maf comp I have to use to get my wideband to meet the afr estimate?

Example increasing global fuel from -47.7 to say -30.3 and my MAF should require less compensation to make the wideband and afr estimate match?

Trying to explain the history better to ensure I get the best answers.

I changed my injectors from 450 to 850 and removed my surge tank. I adjusted my global fuel per ECMLink calculate then I started dialing in my MAF and noticed it was going way high.

Previously when I had it dialed in before on 450cc injectors, I was running the car at 20psi up to 2000hz and the MAFComp didn't go above 20% through the 2000hz range. Then, global fuel was at 0 and injectors dead time was at 0. My wbfactor hovered around 0 through the range and my wideband afrs matched afr estimate through the range.
 
Yes, closer to zero is more fuel. Use the MAF sliders to dial in the MAF(match BoostEst and actual boost at or near 5500) and use the global fuel to dial in injectors. Lots of fine tuning besides that but that'll get you started.
 
Yes, closer to zero is more fuel. Use the MAF sliders to dial in the MAF(match BoostEst and actual boost at or near 5500) and use the global fuel to dial in injectors. Lots of fine tuning besides that but that'll get you started.

OK thanks will try it and report back.


When you say at or near 5500 what do you mean?

I normally do pulls in third gear from 2000 - 7500rpm using maf raw to adjust sliders based on the wbfactor and mafraw.

Are you saying only use the reading at 5500rpm to adjust?
 
On a stock cams/intake manifold vehicle 5500 seems to be the most accurate in terms of ve of the engine. After that you'll notice the BoostEst will slowly drop even if actual boost status stays flat. At this point you really are just adjusting MAF sliders to keep your AFREst a close to actual AFRs as possible.
 
On a stock cams/intake manifold vehicle 5500 seems to be the most accurate in terms of ve of the engine. After that you'll notice the BoostEst will slowly drop even if actual boost status stays flat. At this point you really are just adjusting MAF sliders to keep your AFREst a close to actual AFRs as possible.

ok thanks!
 
On a stock cams/intake manifold vehicle 5500 seems to be the most accurate in terms of ve of the engine. After that you'll notice the BoostEst will slowly drop even if actual boost status stays flat. At this point you really are just adjusting MAF sliders to keep your AFREst a close to actual AFRs as possible.

So none of this solved the issue, I think i'm going to put my surge tank back in to see if it solves the issue. Maybe the pump in my tank is dropping pressure while in boost. The Bosch 044 in the surge tank may hold the pressure better because it is 6 inches from the rail.
 
Can someone help me out, I took my surge tank out and now am just running from the intank pump only. Pump is a Aeromotive 340
What fuel regulator are you running with that fuel pump? Might want to verify that your holding pressure correctly.
 
What fuel regulator are you running with that fuel pump? Might want to verify that your holding pressure correctly.

I have the one below, with a different gauge. With my bosch 044 in a surge tank the needs holds steady, with this pump it jumps maybe 1 psi while idling.

I'm not sure what it is doing while i'm running. Can't tell.

https://www.summitracing.com/tx/parts/tnk-afpr1/overview/

I have an Aeromotive 340 in the tank so it should have no issue. Charts show it flows just as much as the 044.
 
I have the one below, with a different gauge. With my bosch 044 in a surge tank the needs holds steady, with this pump it jumps maybe 1 psi while idling.

I'm not sure what it is doing while i'm running. Can't tell.

https://www.summitracing.com/tx/parts/tnk-afpr1/overview/

I have an Aeromotive 340 in the tank so it should have no issue. Charts show it flows just as much as the 044.
Did you end up figuring out what was causing your sliders to go so high? I might be having the same issue and I'm digging through the forums to see how people handled it.
 
I just needed to do the siphon mod, I was pulling to much fuel, once I drilled out the siphon per vfaw spec, all of my fuel issues went away.
 
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