ECMlink Very high VE table values under boost. Running lean.

[jakk220]

Post a good 3rd gear pull and I'll tweak your VE table, and set global where it should be. You can then do a pull on that tune and see where you're at. I also need a shot of your injecor flow rates, and the voltages if you have them.

Here is the injector flow chart. Getting ready to go get the log now.

 

[GST with PSI]

Set your base fuel pressure back to 43.5psi before you grab the log.

 

[jakk220]

Set your base fuel pressure back to 43.5psi before you grab the log.

Ok, so here is the log. I went to set my base fuel pressure back to 43.5 before I did the pull. The sensor would not seem to go below like 58. The car eventually stalled out because I lowered it too much. Odd. So the sensor is not reading below 58. Which might be out of its range or something. So I went to put my mechanical gauge back on and picked it up and heard a little rattle. I put it on and its not working properly.

So I took a guess and set it back close to where it was based of my logged fuel pressure sensor, actually a tad higher. Now the car was much more rich. Long story short, I'm wondering if the original mechanical gauge was reading inaccurate when I originally set it, and now the electrical sensor one is just not reading right because its not specifically designed for the regulator.

Im going to hit the gym for a little while to blow some steam off and then head to Summit racing and pick up a new mechanical gauge and see what the fuel pressure reads on the new gauge.

 

[GST with PSI]

I'll take a look at the log when I get home later on. Sounds like your base fuel pressure has been the problem all along.

You'll definitely need to get a good mechanical gauge to verify base fuel pressure. Without knowing exactly what your base fuel pressure is, and if it's accurate, tweaking your VE table and global fuel values are going to be worthless.

Verify your base fuel pressure, and then upload another log later on.

An easy way to set base fuel pressure is with the car off and ignition on, activate the pump with ECMlink and set the regulator to your desired pressure (43.5 in your case). Once it's set, start the car and let it get up to temp. At idle, remove the vacuum line from the regulator and check the pressure again. It should be close, if not perfect already. If it's not, make any small adjustments necessary and you should be good.

 

[jakk220]

I'll take a look at the log when I get home later on.

You'll definitely need to get a good gauge to verify base fuel pressure. Without knowing exactly what your base fuel pressure is, and if it's accurate, tweaking your VE table and global fuel values are going to be worthless.

Verify your base fuel pressure, and then upload another log later on.

An easy way to set base fuel pressure is with the car off and ignition on, activate the pump with ECMlink and set the regulator to your desired pressure (43.5 in your case). Once it's set, start the car and let it get up to temp. At idle, remove the vacuum line from the regulator and check the pressure again. It should be close, if not perfect already. If it's not, make any adjustments necessary and you should be good.

Will do. Im hoping that gauge was broken when I first used it to set the pressure so I can get this issue sorted out.

 

[Vegas Smith]

Ok, so here is the log. I went to set my base fuel pressure back to 43.5 before I did the pull. The sensor would not seem to go below like 58. The car eventually stalled out because I lowered it too much. Odd. So the sensor is not reading below 58. Which might be out of its range or something. So I went to put my mechanical gauge back on and picked it up and heard a little rattle. I put it on and its not working properly.

So I took a guess and set it back close to where it was based of my logged fuel pressure sensor, actually a tad higher. Now the car was much more rich. Long story short, I'm wondering if the original mechanical gauge was reading inaccurate when I originally set it, and now the electrical sensor one is just not reading right because its not specifically designed for the regulator.

Im going to hit the gym for a little while to blow some steam off and then head to Summit racing and pick up a new mechanical gauge and see what the fuel pressure reads on the new gauge.

I almost bought that fuel pressure sensor but it had a lot of bad reviews due to quality and inaccuracy. I guess that comes with a $20 parts when it's next competitor is $120.....I guess we will both have to save for the Autometer one

 

[SOADweskey]

I have had great luck with the 0-150psi sensor from Zeitronix. It isn't the cheapest but it quality and made to last.
http://www.zeitronix.com/installation/mapinstallation.shtml

 

[jakk220]

I almost bought that fuel pressure sensor but it had a lot of bad reviews due to quality and inaccuracy. I guess that comes with a $20 parts when it's next competitor is $120.....I guess we will both have to save for the Autometer one

I guess from what Kenny said the purpose was just to check if boost was going up 1:1 with boost. Not necessarily accuracy. I might be able to adjust parameters to get it to read properly. Im at summit racing now picking up the gauge and then heading home to put it on.

 

[jakk220]

I'll take a look at the log when I get home later on. Sounds like your base fuel pressure has been the problem all along.

You'll definitely need to get a good mechanical gauge to verify base fuel pressure. Without knowing exactly what your base fuel pressure is, and if it's accurate, tweaking your VE table and global fuel values are going to be worthless.

Verify your base fuel pressure, and then upload another log later on.

An easy way to set base fuel pressure is with the car off and ignition on, activate the pump with ECMlink and set the regulator to your desired pressure (43.5 in your case). Once it's set, start the car and let it get up to temp. At idle, remove the vacuum line from the regulator and check the pressure again. It should be close, if not perfect already. If it's not, make any small adjustments necessary and you should be good.

Ok I got the base fuel pressure set. 43.5 on the dot. It looks much better but still seems a bit lean for how high the VE table values are. Should I add more fuel via the global and lower the VE numbers or should I give the fuel pressure a little bump?

Here is a log for you to look over and tweak if you have the time. I just need to get it somewhat right so Kenny can continue on with tuning

 

[GST with PSI]

I just looked over your log, and something is just not adding up.

Your global fuel value should be the following:

You must be logged in to view this image or video.

Now, given your global fuel is already set way richer than the value above, and your VE table is also set ridiculously rich, there should be no reason why you're not seeing this in your actual AFRs. Also, your injector duty cycle is low, which to me would not indicate them being overly worked by the current tune.

Something else has to be awry, here. I've got a few additional questions:

1) Have you tested the ethanol content of your fuel? Is it actually E85 grade?
2) What brand and model of wideband O2 are you running, and when was the last time it was calibrated?
3) And you absolutely positive your base fuel pressure is currently 43.5 PSI?

Your actual AFR tracks target AFR fairly well. However, your VE table is completely jacked, and your global is way off from where it should be. I could absolutely dial in your VE table, and bump global richer to get your AFRs lining up, but it wouldn't be right. There's still some underlying issue here, and tuning around it isn't the solution.

BTW, you don't need a fuel pressure sensor to verify your AFPR is raising fuel pressure 1:1 with boost. You can use a hand held vacuum pump, or an air compressor with an adjustable regulator to verify that. Simply set the compressor regulator to say, 10 psi, and hook a vacuum line from the AFPR to an air nozzle on the compressor. The mechanical gauge on your AFPR should read whatever your base fuel pressure is plus whatever the air compressor's regulator is set at. Much easier, and a more accurate way to check fuel pressure is rising at the appropriate rate.

 

[jakk220]

I just looked over your log, and something is just not adding up.

Your global fuel value should be the following:

You must be logged in to view this image or video.

Now, given your global fuel is already set way richer than the value above, and your VE table is also set ridiculously rich, there should be no reason why you're not seeing this in your actual AFRs. Also, your injector duty cycle is low, which to me would not indicate them being overly worked by the current tune.

Something else has to be awry, here. I've got a few additional questions:

1) Have you tested the ethanol content of your fuel? Is it actually E85 grade?
2) What brand and model of wideband O2 are you running, and when was the last time it was calibrated?
3) And you absolutely positive your base fuel pressure is currently 43.5 PSI?

Your actual AFR tracks target AFR fairly well. However, your VE table is completely jacked, and your global is way off from where it should be. I could absolutely dial in your VE table, and bump global richer to get your AFRs lining up, but it wouldn't be right. There's still some underlying issue here, and tuning around it isn't the solution.

BTW, you don't need a fuel pressure sensor to verify your AFPR is raising fuel pressure 1:1 with boost. You can use a hand held vacuum pump, or an air compressor with an adjustable regulator to verify that. Simply set the compressor regulator to say, 10 psi, and hook a vacuum line from the AFPR to an air nozzle on the compressor. The mechanical gauge on your AFPR should read whatever your base fuel pressure is plus whatever the air compressor's regulator is set at. Much easier, and a more accurate way to check fuel pressure is rising at the appropriate rate.

Thanks. To answer your questions:

1. I have not tested the ethanol content. I get it from the pump so it could vary and I figured there was not really a point in testing it. I will order a test tube tonight and test it asap. I would imagine that if the Ethanol content is lower than advertised it would be more rich, not lean.

2. I am running an AEM wideband which cant be calibrated as I'm sure you know. The sensor has probably about 10k miles or so on it.

3. The base fuel pressure I just set with a brand new fuel lab gauge that I bought at summit racing. My regulator is also a fuel lab so I am fairly confident that it is right.

Also, I verified that boost was going up 1:1 with boost via the sensor that Kenny had me buy and install. It just was not being logged in the last one because I had my new mechanical gauge hooked up in its spot.

I would be willing to do the test that you stated above just to 100% confirm. It never hurts to test something more than one way. I will do this test here in the next day or so and report my findings. But from what I have logged with the electronic sensor, It is going up 1:1.

Now I have one question as well that I am hoping you can answer. My math may be off here but I'm getting a scaling of 850 injectors from my math. Here is how I have come to the conclusion from ECMlink's website.

The injectors that I have flow 11% less right of the rip with E85 due to viscosity differences. This is a chart from FIC showing their test results. The flow testing done in my chart was based on gas not E85.

You must be logged in to view this image or video.

So with this being factored in 1450*11%=159.5 with 159.5 being the amount of CC's less that they flow
1450-159.5=1290.5

So then I ran the calculations from this ECMlink page by this chart



Fuel Stoich AFR Gas ratio
Gas 14.7 1.00
E10 14.08 0.96
E70 10.6975 0.7287
E85 9.8526 0.670
E100 9.0078 0.613


For E85 on injectors that flow 1290.5 on E85: 1290.5*0.670 = 864.6cc

Then the formula used to calculate the global%: Adj = (100 * ( 450 / NewInjFlow ) ) - 100

(100*(450/864.5))-100 = -47.9%

Just manually doing the math from the ECMlink sites that is what I am getting. I do not want to doubt the way you are calculating it, because that should work as well, but I just want to know why mine is wrong so I can better understand.

I do feel as though even scaled with lower injectors the VE table still is not right. However I will upload another settings file that Kenny sent me that we have been using since the injectors were scaled based on my calculations and the fuel pressure was fixed. The attached file is what my VE table currently looks like and we still have some room to pull more off of it. I will upload a log on those settings when I get home tonight.

 

[GST with PSI]

The calculator in ECMlink is just used to give you an approximate starting point. It's not the end all be all. However, most of the time if you start deviating too far from the calculated values, that would suggest there's an underlying issue. If you suspect your injectors are flowing less than they should be on E85, then make the appropriate adjustment and run with it.

 

[jakk220]

The calculator in ECMlink is just used to give you an approximate starting point. It's not the end all be all. However, most of the time if you start deviating too far from the calculated values, that would suggest there's an underlying issue. If you suspect your injectors are flowing less than they should be on E85, then make the appropriate adjustment and run with it.

I was just going off of what the calculations were from the website. I might call FIC and email ECMlink and see what they can tell me. deep down I feel there is still something that is not entirely right. I will check the fuel pressure rising 1:1 manually like you said and see what the results are. Were supposed to keep tuning the car here this week sometime so ill see how that goes as well.

I will send the picture of the global fuel you posted to ECMlink and my calculations as well and see if they can verify which one is closer to being correct and report back.

 

[miliman13]

2. I am running an AEM wideband which cant be calibrated as I'm sure you know. The sensor has probably about 10k miles or so on it.

????? Really

 

[jakk220]

????? Really

Yeah the only calibrating you can do is adjusting the voltage settings or something like that to get the numbers link shows to match your gauge. That I have had to do before because they used to not match up quite right.

 

[jakk220]

The calculator in ECMlink is just used to give you an approximate starting point. It's not the end all be all. However, most of the time if you start deviating too far from the calculated values, that would suggest there's an underlying issue. If you suspect your injectors are flowing less than they should be on E85, then make the appropriate adjustment and run with it.

Still waiting on the E85 tester. In the meantime I'm going to be replacing the feed line with -8 AN and using the stock feed as the return. I have heard that the stock return can be a restriction not allowing enough fuel to return to the tank fast enough causing a lean condition.

Have you ever heard of this happening? I'm also going with a summit racing fuel filter to eliminate that restriction as well.

There will be a bulkhead fitting off of the pump to do what kenny suggested.

 

[Vegas Smith]

I have heard of those things happening but never owned a car fast enough to experience them.

 

[Mello]

A restriction after the injectors could not cause a lean condition. If the regulator or return line was a restriction the fuel pressure would start not being 1:1, pressure would increasing more than 1:1 & should cause things to drift rich the more the pressure goes beyond 1:1.

 

[jakk220]

I have heard of those things happening but never owned a car fast enough to experience them.

I don't think its even an issue of the car being fast but just the size of the fuel pump .

A restriction after the injectors could not cause a lean condition. If the regulator or return line was a restriction the fuel pressure would start not being 1:1, pressure would increasing more than 1:1 & should cause things to drift rich the more the pressure goes beyond 1:1.

I think the pressure not being 1:1 would be more of a feed issue or a vacuum line issue going to the regulator. Anything after that I believe the FPR would compensate for. Either way I am doing it to eliminate the possibility that somehow it is the issue. While the VE table looks better I'm not convinced that its entirely fixed.

 

[Mello]

Your logic on your fuel system is flawed. When there is a resistriction you will have high pressure before & low pressure after. You could only have a lean condition if the restriction is before the injectors/regulator. If the restriction was after the injectors/regulator (ie: the return line) you would get a high pressure condition at the injector which would upset the 1:1 linear pressure increase & cause a rich condition. Another thing that does not add up is your issue is at trottle. You're using more fuel WOT & there should be less trying to return to the tank. Proper balanced with high IDC almost no fuel would be returning as it's all being injected. If the return was a restriction it should show up at idle & low fuel demand, not when more fuel is needed. I would look for a leak. It may not leak at base pressure but it may start leaking & not holding pressure as the fuel line pressure increases (similar to coolant leak testing with a coolant pressure tester).

 

[jakk220]

Your logic on your fuel system is flawed. When there is a resistriction you will have high pressure before & low pressure after. You could only have a lean condition if the restriction is before the injectors/regulator. If the restriction was after the injectors/regulator (ie: the return line) you would get a high pressure condition at the injector which would upset the 1:1 linear pressure increase & cause a rich condition. Another thing that does not add up is your issue is at trottle. You're using more fuel WOT & there should be less trying to return to the tank. Proper balanced with high IDC almost no fuel would be returning as it's all being injected. If the return was a restriction it should show up at idle & low fuel demand, not when more fuel is needed. I would look for a leak. It may not leak at base pressure but it may start leaking & not holding pressure as the fuel line pressure increases (similar to coolant leak testing with a coolant pressure tester).

I understand where you are coming from. But I have tested the system at 70 psi and there were no leaks. I have also tested the fuel pressure in boost and it goes up 1:1. I truly am running out of options here. The only things I can think of to even replace anymore are the fuel pump, the wideband, and the fuel lines.

I highly doubt that it is any of those, but after that I can say I have replaced and tested the entire fuel system.

 

[jakk220]

Your logic on your fuel system is flawed. When there is a resitriction you will have high pressure before & low pressure after. You could only have a lean condition if the restriction is before the injectors/regulator. If the restriction was after the injectors/regulator (ie: the return line) you would get a high pressure condition at the injector which would upset the 1:1 linear pressure increase & cause a rich condition. Another thing that does not add up is your issue is at trottle. You're using more fuel WOT & there should be less trying to return to the tank. Proper balanced with high IDC almost no fuel would be returning as it's all being injected. If the return was a restriction it should show up at idle & low fuel demand, not when more fuel is needed. I would look for a leak. It may not leak at base pressure but it may start leaking & not holding pressure as the fuel line pressure increases (similar to coolant leak testing with a coolant pressure tester).

Also the way I'm thinking of it is yes, a return line issue would raise the pressure but it would also lower the flow throughout the whole system. It would essentially be backed up. Which I couldn't see it making it run rich that way.

And yes, you do use more fuel when at WOT, but I doubt I am using enough to not have any returning to the tank. In my head that would require me to be maxing out my fuel pump which I am not doing. Not to mention im not even at a high boost setting yet.

 

[Mello]

I understand your frustration. From everything I've read, it's like everything is inside out. I don't think I agree with a restriction causing a lean condition due to less flow. Example, if you completely block the return & could go max IDC's your flow would eventually equal almost 6 liters. In your case the flow would stabilize at whatever pressure 4 x 1450cc would be. The only problem with no return is you can't control pressure making the throughput flow irradic.

Just a thought but I have seen software (tuning software actually) that when looking at the input setting, they look correct. But they were actually screwed up because of a software glitch. The fix was go back & re-enter the data & up load. I'd try it some of your fuel stuff like the injector dead times. Can't hurt.

 

[Mello]

Have you test your fuel pump voltage as this is happening? I checked your profile; have re- wired your 450? Are you see a voltage drop at your fuel pump? What shape is your alternator in?

 

[jakk220]

Have you test your fuel pump voltage as this is happening? I checked your profile; have re- wired your 450? Are you see a voltage drop at your fuel pump? What shape is your alternator in?

Yes I rewired it with the STM kit. I have not tested the voltage while it is in boost but at idle I believe it was 13.5 when I checked it. The alternator is brand new as I was just fighting charging issues right before this.