May someone please help diagnose my data log?

[kevinmoua1]

i dont know what is going on with my car! my first day data logging with my friend and he said my numbers are very odd. my car feels nothing like his and we have very similar mods. car is a 2002 wrx. catless turboback, cobb stage 2 ACN1 91, and a aem short ram.

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[SouthernWRX]

Post the data log so folks can take a look at it. You can use google docs to do this, just make sure to change permission from private to public.

[tmcgraw]

It looks to me like there is something wrong with your air/fuel ratios. Cobb is usually on here in the mornings and may be able to help more but it looks to me like you need to try a different map or have some major modifications done to your current one.

[Cobb Tuning]

Originally Posted by kevinmoua1

i dont know what is going on with my car! my first day data logging with my friend and he said my numbers are very odd. my car feels nothing like his and we have very similar mods. car is a 2002 wrx. catless turboback, cobb stage 2 ACN1 91, and a aem short ram.

You have a major mechanical problem with the car that is causing extreme perceived lean condition and the resulting extreme positive fuel trims (A/F Learning 1). There are a number of potential causes but the first thing that stands out is that you are using an unsupported intake for the map. Only the Cobb SF or stock intake are supported by our OTS maps for this car. Use of any other intake can potentially cause load errors which will cause fueling and ignition timing to be off. This is not only bad for performance, but can also cause knock and possible engine damage. You have some extreme learned knock in the higher RPM range and the DAM has dropped low as well that is likely due to the fueling issue.

You could have other mechanical issues as well, but for now I would not do anything (and no more WOT or heavy throttle runs) until you get the stock or Cobb SF intake installed. When you do, reset the ECU via the troubleshooting menu on the AccessPORT and then drive through about a tank of gas and check your A/F Learning 1 A, B, C, and D values again. They should generally be within +/- 5%. If you still have a problem then, you might have another issue such as intake tract leak, bad MAF or bad front o2.

Bill

[kevinmoua1]

Originally Posted by Cobb Tuning

You have a major mechanical problem with the car that is causing extreme perceived lean condition and the resulting extreme positive fuel trims (A/F Learning 1). There are a number of potential causes but the first thing that stands out is that you are using an unsupported intake for the map. Only the Cobb SF or stock intake are supported by our OTS maps for this car. Use of any other intake can potentially cause load errors which will cause fueling and ignition timing to be off. This is not only bad for performance, but can also cause knock and possible engine damage. You have some extreme learned knock in the higher RPM range and the DAM has dropped low as well that is likely due to the fueling issue.

You could have other mechanical issues as well, but for now I would not do anything (and no more WOT or heavy throttle runs) until you get the stock or Cobb SF intake installed. When you do, reset the ECU via the troubleshooting menu on the AccessPORT and then drive through about a tank of gas and check your A/F Learning 1 A, B, C, and D values again. They should generally be within +/- 5%. If you still have a problem then, you might have another issue such as intake tract leak, bad MAF or bad front o2.

Bill

so before i even checked this thread again i put the stock intake back in and resetted the ecu. car feels much better and looks like better numbers but still not hitting full boost.

[kevinmoua1]

stage 2 hwg map

[tmcgraw]

That's a step in the right direction from before.

[Cobb Tuning]

Originally Posted by kevinmoua1

stage 2 hwg map

If these logs are with the stock intake after ECU reset, you still have a problem with fueling. Your "C" range A/F Learning 1 is rapidly increasing and the last log show it at 7%. I would keep driving to see where they end up. There may still be a problem that you need to address (such as an intake tract leak, bad MAF or bad front o2). I would do that before trying to solve the low boost issue.

Bill

[kevinmoua1]

Originally Posted by Cobb Tuning

If these logs are with the stock intake after ECU reset, you still have a problem with fueling. Your "C" range A/F Learning 1 is rapidly increasing and the last log show it at 7%. I would keep driving to see where they end up. There may still be a problem that you need to address (such as an intake tract leak, bad MAF or bad front o2). I would do that before trying to solve the low boost issue.

Bill

did the stage 2 map with the stock intake look better or the one with the hwg map?

[Cobb Tuning]

Originally Posted by kevinmoua1

did the stage 2 map with the stock intake look better or the one with the hwg map?

The fuel trim issue won't be effected by the different maps you are trying. That is a mechanical issue. Reflashing a map will clear your trims and make them look better temporarily and the trims can vary over time, but I would drive through about a tank of gas without reflashing or resetting the ECU and see where they end up. I wouldn't do any more WOT runs for now.

Bill

[kevinmoua1]

Originally Posted by Cobb Tuning

The fuel trim issue won't be effected by the different maps you are trying. That is a mechanical issue. Reflashing a map will clear your trims and make them look better temporarily and the trims can vary over time, but I would drive through about a tank of gas without reflashing or resetting the ECU and see where they end up. I wouldn't do any more WOT runs for now.

Bill

should i reset ecu and reflash and then run through a tank of gas?

[Cobb Tuning]

Originally Posted by kevinmoua1

should i reset ecu and reflash and then run through a tank of gas?

If you reset the ECU when you put the stock intake back on, then you don't need another reset. Just do some normal driving for about a tank of gas periodically taking a peak at the A, B, C, D trims.

Bill

[kevinmoua1]

Originally Posted by Cobb Tuning

If you reset the ECU when you put the stock intake back on, then you don't need another reset. Just do some normal driving for about a tank of gas periodically taking a peak at the A, B, C, D trims.

Bill

will do so and i will update you with a data log once i've done so.

[kevinmoua1]

after a tank of gas

[Andrewxxcarlson]

Hmmm, got sum knock again. Based on your MAF seeming relatively low through the higher rpms I'd reccommend cleaning the MAF. See how that goes and try again.

[Cobb Tuning]

Originally Posted by kevinmoua1

after a tank of gas

Your DAM has dropped which is an indication of knock. Your long-term fuel trims for "C" is still a problem.

Try swapping out your MAF sensor with your friends temporarily, reset the ECU (via the troubleshooting menu on AP) and do the same WOT run as the last log. We can then compare the peak mass airflow and see if it is noticeably higher than your previous log. If so, then the MAF sensor is the likely cause of your issues. If that is the case, you can try cleaning yours and if that doesn't work, you may have to get a new one.

Besides the MAF sensor, the two other most common issues that can cause extreme fuel trims are post-MAF intake tract leaks (do a pressure/smoke test of intake tract to be sure) and bad front o2.

Bill