Need some datalog help .... Seems rich to me or am I wrong

[ehazel]

Ok so thats ok then. I just gotta figure out the fat lamda then

Ive never messed with SCT so I cant really give much guidance on that front with the fuel source, It could have a different name or just not exist.

If there is a big discrepancy between commanded vs actual and your trims are all over the place then I would think your looking at maf sensor issue, stuck injector, or an aftermarket intake that wasn't tuned for, or vise versa being tuned for a intake that you don't have. (Maf housing with a different ID from stock) If your boosted you could have a big air leak between the maf sensor and cylinders under boost.

Uncommanded rich when na = over metered air or bad injector data.

But with any of those your worry wouldn't be about running rich, you would be lucky for it to idle.

My guess is your tuner is just commanding it for some reason or exhaust protections.

For reference I looked at a stock Mach 1 file and here are the commanded values for both WOT power demand and the exhaust protections including catalyst.

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[horsepower addiction]

High flow cats without a tune sometimes throw a check engine light and this could explain the problems. Also vacuum leak or dirty maf sensor

 

[dragonfueled]

Ive never messed with SCT so I cant really give much guidance on that front with the fuel source, It could have a different name or just not exist.

For reference I looked at a stock Mach 1 file and here are the commanded values for both WOT power demand and the exhaust protections including catalyst.

Damn ok thank you. Yeah I'm way richer. I did remove the carbon trap in the stock mach1/350 cai which the tuner knows about. I would think if anything that would of leaned it out though.
I'm gonna do a complete datalog again and send it in.

High flow cats without a tune sometimes throw a check engine light and this could explain the problems. Also vacuum leak or dirty maf sensor

Has o2 spacers. Trims at idle are perfect. Mass air is clean . Car only has 4k on it.
It feels fine just seeing 10.8 on the dash infered air fuel prompted me to log and see the .76. I'll ask em to look at the log hopefully they do

 

[Pistol_91]

Max enrichment = .70 lambda @ 1650 degree cat temps.

This is what he's talking about. Power enrichment will bring it to the .82 lambda and cat protection can potentially bring that .82 to .70.

Meaning .76 is normal.

This is literally nothing to worry about. If you have concerns I'd contact your tuner and ask them about it since they're the one with your file.

 

[ehazel]

Max enrichment = .70 lambda @ 1650 degree cat temps.

This is what he's talking about. Power enrichment will bring it to the .82 lambda and cat protection can potentially bring that .82 to .70.

Meaning .76 is normal.

This is literally nothing to worry about. If you have concerns I'd contact your tuner and ask them about it since they're the one with your file.

Exactly this.

One thing to add is Cat over-temp doesn't equal instant max enrichment. That is the maximum the ecu is allowed to hit while attempting to cool the catalyst temperature and get it back below 1630. So if it can achieve < 1630 at .76 that is as far as it will go and start heading back to .82 if the temperature will allow.

 

[dragonfueled]

Exactly this.

One thing to add is Cat over-temp doesn't equal instant max enrichment. That is the maximum the ecu is allowed to hit while attempting to cool the catalyst temperature and get it back below 1630. So if it can achieve < 1630 at .76 that is as far as it will go and start heading back to .82 if the temperature will allow.

I get that. But logged with inferred cat temp at 1100 and still went rite to .76. seems like as soon as it hits 6k it drops from .82 to .76.
Would the stft still pull 18% during cot? Genuine question.

 

[ehazel]

I get that. But logged with inferred cat temp at 1100 and still went rite to .76. seems like as soon as it hits 6k it drops from .82 to .76.
Would the stft still pull 18% during cot? Genuine question.

Think of the trims as a air/fuel error %. Say the ecu is commanding 1.0 lambda, but the front o2 sensors are saying we are only measuring 1.01 lamda.

The cause of the difference between the two could be any number of things, old, dirty, out of spec, maf/o2 sensors, air leaks/small amounts un-measured air, injectors that spray slightly more or less than they are suppost to. Then on the tuning side there can also be bad calibration data behind those sensors and injectors. So even if they work correctly the ecu is interpreting the feedback slightly incorrectly or telling the injectors to fire at or for the wrong amount of time.

The ecu uses the longterm + short term trims to fix those slight inaccuracies automatically by saying, I know I'm suppose to be at 1.00 but for some reason I'm actually at 1.01, so Im going to "trim" by adding 1% fuel, check my o2 sensors again, and verify I should now be measuring 1.0 lamda. This is the Closed loop logic where the ecu is constantly making sure we are running at the fueling that the tuner has defined.

So this is why commanded vs actual measured lambda comes into your question. If you are seeing .82 commanded, but measured is .76 there is something going on that the ecu doesn't know about, it would then be correcting for with the trims.

If you are seeing .76 commanded and .76 measured, Then the ecu is fully in control of the lambda and following whatever logic is defining the commanded lambda.

This is purely an example of what that logic could look like:

WOT table says to run .82 then there is a multiplier table that says its really hot outside so add 5% fuel. (could be any number of different factors) As this is logic, our trims would still be 0 because yes we are adding 5% fuel but that's just what the ecu has been programed to command.

Now layer on the Exhaust temp protection, Some smart person figured out you can in fact add fuel to a fire to cool it down. So we hit our temp limit and start adding 20% fuel to cool it down. We run into the same thing, we are now technically adding 5% + 20% fuel, but our trims should still be 0. (at-least in a perfect world)

So with that you should be able to look at the logs and see my commanded is .76 and my measured is .76 with 0% trims, so for some reason my tuner has decided that's where I need to be running at.

Or my commanded is .82 and my measured is .76 with crazy fuel trims, then its time to start working with your tuner to figure out if there's potentially something wrong with the vehicle, or there is something incorrect on the tune side causing the ecu to not 100% know what is going on.

 

[dragonfueled]

Think of the trims as a air/fuel error %. Say the ecu is commanding 1.0 lambda, but the front o2 sensors are saying we are only measuring 1.01 lamda.

The cause of the difference between the two could be any number of things, old, dirty, out of spec, maf/o2 sensors, air leaks/small amounts un-measured air, injectors that spray slightly more or less than they are suppost to. Then on the tuning side there can also be bad calibration data behind those sensors and injectors. So even if they work correctly the ecu is interpreting the feedback slightly incorrectly or telling the injectors to fire at or for the wrong amount of time.

The ecu uses the longterm + short term trims to fix those slight inaccuracies automatically by saying, I know im suppost to be at 1.00 but for some reason I'm actually at 1.01, so Im going to "trim" by adding 1% fuel, check my o2 sensors again, and verify I should now be measuring 1.0 lamda. This is the Closed loop logic where the ecu is constantly making sure we are running at the fueling that the tuner has defined.

So this is why commanded vs acutal measured lambda comes into your question. If you are seeing .82 commanded, but measured is .76 there is something going on that the ecu doesnt know about, it would then be correcting for with the trims.

If you are seeing .76 commanded and .76 measured, Then the ecu is fully in control of the lambda and following whatever logic is defining the commanded lambda.

This is purely an example of what that logic could look like:

WOT table says to run .82 then there is a muliplier table that says its really hot outside so add 5% fuel. (could be any number of different factors) As this is logic, our trims would still be 0 becuase yes we are adding 5% fuel but thats just what the ecu has been programed to command.

Now layer on the Exhaust temp protection, Some smart person figured out you can infact add fuel to a fire to cool it down. So we hit our temp limit and start adding 20% fuel to cool it down. We run into the same thing, we are now technically adding 5% + 20% fuel, but our trims should still be 0. (atleast in a perfect world)

So with that you should be able to look at the logs and see my commanded is .76 and my measured is .76 with 0% trims, so for some reason my tuner has decided thats where I need to be running at.

Or my commanded is .82 and my measured is .76 with crazy fuel trims, then its time to start working with your tuner to figure out if theres potentialy something wrong with the vehicle, or there is something incorrect on the tune side causing the ecu to not 100% know what is going on.

Lambse which I believe is commanded is .82.. so yeah something is causing it to go rich. Stft was .87 so it's trying to lean it out.
Log sent to tuner. We shall see

 

[horsepower addiction]

Any time you go wot the tune defaults to open loop so the fuel trims aren’t doing anything. It goes straight to a preset lambda based on engine temp and rpm. Has nothing to do with fuel trims and cat temp does not do anything until you hit 1630

 

[horsepower addiction]

Your tuner probably set the wot lambda to what it is showing

 

[horsepower addiction]

Sorry it compares open loop to closed loop with the wide bands and adjust from there

 

[Pistol_91]

The only time the car should be in open loop is at start up for 30 seconds or so. Other than that. It's a closed loop system.......

There's also a temp table under temperature tab that dictates enrichment per exhaust manifold protection via load rpm and mapped point being used.

There's 4 main ways it will enrich, all due to temperature.

EGT control
Exhaust manifold protection
Catalyst protection
Component protection which includes o2 sensor temp protection and exhaust valve temp protection.

All these things enabled can enrich the fuel ratio.

Your cats might not be at 1650 degrees but all these other components may be exceeding that temp, causing enrichment.

I'll repeat, this is normal. Nothing to worry about. Again, this is the way Ford set up this logic. You aren't going to hurt your engine. Contact your tuner if you want it disabled or to raise that .70 max enrichment.

 

[Pistol_91]

Sorry it compares open loop to closed loop with the wide bands and adjust from there

Open loop is never considered in the logic. The model reads fuel trims based on MAF and compares it to the SD model but still, it's primarily based on MAF curve and corrects. Open loop hasn't been used since Ford put widebands in their vehicles and ti-vct was introduced.

 

[ehazel]

One thing I did think of, that I didnt mention before.

Is your stoich set point vs the actual fuel you are running. If this is an e85 tune and you are running 93 or a 93 heavy mix you would see a rich condition that was being corrected for by trims. (lots of negative trim, Like 15-30% if the tune allows it to correct that much) I would however expect a check engine light for running rich on banks 1&2.

 

[dragonfueled]

The only time the car should be in open loop is at start up for 30 seconds or so. Other than that. It's a closed loop system.......

There's also a temp table under temperature tab that dictates enrichment per exhaust manifold protection via load rpm and mapped point being used.

There's 4 main ways it will enrich, all due to temperature.

EGT control
Exhaust manifold protection
Catalyst protection
Component protection which includes o2 sensor temp protection and exhaust valve temp protection.

All these things enabled can enrich the fuel ratio.

Your cats might not be at 1650 degrees but all these other components may be exceeding that temp, causing enrichment.

I'll repeat, this is normal. Nothing to worry about. Again, this is the way Ford set up this logic. You aren't going to hurt your engine. Contact your tuner if you want it disabled or to raise that .70 max enrichment.

I would have to datalog fuel source to know for sure. Odd though that is would be in some sort of protection basically all the time. It's not like I'm beating on the car then dataloging. My point is literally the first wot hit after warming up is still rich as hell. Can't see any of the protection kicking in when all I was doing is low rpm cruising then one quick gear pull.

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