Cobb E30 Logs - Help Please

[Danny271]

I loaded the Cobb OTS E30 map today. I filled up with 6 gallons of E85 and the rest 93 octane.

I logged 2 runs, please see .zip file. The first run is a 3rd gear pull, and the second run is a 4th gear pull.

Manual transmission, all wheel drive, DTC left on (I think...)

Mods:
Evolution Racewerks FMIC
Evolution Racewerks Chargepipe w/Forge DV
CP-e Downpipes
BMS DCI & OCC

Any input as to how my graphs look would be greatly appreciated. I'm heading to Englishtown Raceway next Saturday for some glory 1/4 mile runs and wanted to see if I should switch back to the non-e30 map or if this new map is safe to run without any ATR changes.

The car registered a P2AAF code, fuel pump plausibility, when I first went WOT after installing the E30 tune. I cleared the code, and it never came back after all of my runs (30 minutes of hard driving).

Thanks for your help in advance!

P.S. I may or may not have ran into a FBO E92 M3 while datalogging. He was certainly surprised with the outcome! :dance:

[ATP]

My noob interpretations on the 4th gear pull:

Looks like several timing corrections on several different cylinders (1, 2, and 6).
Your AFR seems to lean out a bit at the initial WOT (I am guessing thats when you went WOT, you should log TPS) but I dont think its anything to be concerned with.
STFTs hit the low-mid 20's so you arent maxing those out which is good.
Your LPFP seems to be struggling to keep up in the lower RPMs and thats probably the reason you triggered the code.

Overall, probably not too bad. You need to log TPS and the actual throttle blade position. Might need to narrow down what the timing pulls are related to as well.

[lulz_m3]

4th gear pull look looks good, your fuel scalar could be increased to lower the STFT's if your comfortable making those changes in the Cobb ATR program, but as long as you are not pegging out at +/- 34% you're good.

3rd gear log is weird, like the data was reversed since it starts at high rpms and ramps downward, not sure what that is about.

The P2AAF is nothing to worry about, it will show everytime you start the car, and wont illimunate the CEL. Its always shown on my car, and even after having the HPFP changed under the recall its still showing.

How does the car feel to you?

[ATP]

4th gear pull look looks good, your fuel scalar could be increased to lower the STFT's if your comfortable making those changes in the Cobb ATR program, but as long as you are not pegging out at +/- 34% you're good.

3rd gear log is weird, like the data was reversed since it starts at high rpms and ramps downward, not sure what that is about.

The P2AAF is nothing to worry about, it will show everytime you start the car, and wont illimunate the CEL. Its always shown on my car, and even after having the HPFP changed under the recall its still showing.

How does the car feel to you?

For my own curiosity, are the timing pulls on the 4th gear log of no concern?

[lulz_m3]

For my own curiosity, are the timing pulls on the 4th gear log of no concern?

Not in my opinion. The general consensus has been to look for adjacent cylinders pulling 3.38 or more *'s of timing under the same conditions consistently (same load, same rpms). To really analyze things, you should do atleast 5-10 pulls within about 45 mins and look for these consistent timing pulls.

The DME is overly sensitive. I can do 10 pulls and have 5 logs that have 0 timing corrections and the rest pull timing on various cylinders and at different RPM's/load.

[Danny271]

Not in my opinion. The general consensus has been to look for adjacent cylinders pulling 3.38 or more *'s of timing under the same conditions consistently (same load, same rpms). To really analyze things, you should do atleast 5-10 pulls within about 45 mins and look for these consistent timing pulls.

The DME is overly sensitive. I can do 10 pulls and have 5 logs that have 0 timing corrections and the rest pull timing on various cylinders and at different RPM's/load.

So general consensus is to get 5-10 more logs with TPS recorded and come back?

It broke up a little at redline on the 4th gear pull, but every other pull I did (maybe 15 pulls) was very healthy. I was heading home after doing some data logging and ran into an E92 M3 with full bolt ons. We did 1 pull from 60-120 with me starting in the same lane behind him and I had to let off of the throttle as I was catching up to him too quickly. So all-in-all the car feels very strong.

I'll be back with some more logs for you guys to analyze. Thanks for all of your help!

[Carl Morris]

I concur that either your LPFP is almost failing to keep up OR your LP pressure sensor is going bad. I was getting the same code and showing low pressure and thought my pump was going out and the dealer replaced the sensor and I never get that code any more and my logged values are good. I realize that (most?) other people have seen the sensor fail the opposite way.

I think those timing pulls just show that the tuning is being pushed. I personally prefer to tune out the timing pulls so that I know I have more headroom under extreme conditions. So I bumped up the scalars to 1.2 and made it an E50 map and also pulled a bit of timing in a few spots to get it to where I was happy with it. It's an aggressive timing map for E30.

[Danny271]

I concur that either your LPFP is almost failing to keep up OR your LP pressure sensor is going bad. I was getting the same code and showing low pressure and thought my pump was going out and the dealer replaced the sensor and I never get that code any more and my logged values are good. I realize that (most?) other people have seen the sensor fail the opposite way.

I think those timing pulls just show that the tuning is being pushed. I personally prefer to tune out the timing pulls so that I know I have more headroom under extreme conditions. So I bumped up the scalars to 1.2 and made it an E50 map and also pulled a bit of timing in a few spots to get it to where I was happy with it. It's an aggressive timing map for E30.

I also forgot that I didn't turn DTC fully of, I never lose traction being AWD so I often overlook this. I'm also running a higher E85 content than E30, as I filled up with 6 gallons of E85 and 9 gallons of 93 Octane. Could any of these variables have affected my logs?

Either way, I'm going to do some more logging tonight (if time permits) and remember to turn off DTC completely as well as enable the TPS recording. If recommended, I can also add a gallon or two of 93 octane to dilute the fuel mixture and make it closer to E30.

[lulz_m3]

I concur that either your LPFP is almost failing to keep up OR your LP pressure sensor is going bad. I was getting the same code and showing low pressure and thought my pump was going out and the dealer replaced the sensor and I never get that code any more and my logged values are good. I realize that (most?) other people have seen the sensor fail the opposite way.

I think those timing pulls just show that the tuning is being pushed. I personally prefer to tune out the timing pulls so that I know I have more headroom under extreme conditions. So I bumped up the scalars to 1.2 and made it an E50 map and also pulled a bit of timing in a few spots to get it to where I was happy with it. It's an aggressive timing map for E30.

I have a brand new Low pressure fuel sensor and brand new HPFP. I have had the P2AAF code since installing the tune at 20k miles. I agree his LPFP might be on its way out, the logs show his actual Low pressure drop to about 40-45psi, but if your insinuating that the P2AAF code is related to the LPFP i have to disagree.

[bigdnno98]

I have a brand new Low pressure fuel sensor and brand new HPFP. I have had the P2AAF code since installing the tune at 20k miles. I agree his LPFP might be on its way out, the logs show his actual Low pressure drop to about 40-45psi, but if your insinuating that the P2AAF code is related to the LPFP i have to disagree.

+1 P2AAF is a common code when installing Cobb. Cobb was my first tune with 20k miles on the car on 93 oct. I always had P2AAF. When I switched to jb4 code went away. I'll have to check if it came back since I installed the backend flash. I'm not saying the code is never related to fuel pressure sensor or lpfp/hpfp issues but it does sometimes appear when there are no issues. Best to keep an eye on fuel pressure logs.

[Danny271]

I have a brand new Low pressure fuel sensor and brand new HPFP. I have had the P2AAF code since installing the tune at 20k miles. I agree his LPFP might be on its way out, the logs show his actual Low pressure drop to about 40-45psi, but if your insinuating that the P2AAF code is related to the LPFP i have to disagree.

Is my LPFP really operating that poorly? Should I switch back to the non-E30 maps and look into replacing my LPFP and/or my LP Fuel Sensor?

I certainly don't want to continue to run on something if it's going to leave me/my car stranded.

[themyst]

You should be running less E85 than 6 gallons on that map. Explains the issues your fuel system is having. If you want to tune for higher ethanol mixtures change the fuel scalar using the info in the ATR help file.

[VNeBLOB42]

You should be running less E85 than 6 gallons on that map. Explains the issues your fuel system is having. If you want to tune for higher ethanol mixtures change the fuel scalar using the info in the ATR help file.

+1

@Danny271

5 gallons E85 @ 85% ethanol and 11 gallons 93 @ 10% ethanol you will be @ E33 (33% Ethanol). @ 6 gallons you are at E38. (16 gallon tank)

Try to get a better blend and log again. if my calculations are correct, at 3/4 tank (12 gallons) you should add another 4 gallons of 93 to put you at E31. Remember this is all based upon E85 being 85% and 93 being 10%.

try to calculate your best @ each fill up. 4.5/11.5 E85/93 Full tank. Roughly calculate gallons to full and pump in ~29% E85 to 93


I know its splitting hairs easy math is 30% E85 but will put you at E33 which is probably fine.

[Danny271]

Thanks for all of the help/advice everyone!

The E85 that I added 6 gallons of said that it had 68% ethanol content. I decided to add 2 gallons of 93 octane tonight. I drove around for 15-20 minutes and did 3 pulls. The car didn't break up near redline like it did yesterday in one of the pulls. It felt strong tonight, but so did the pulls from yesterday...

Please have a look at my new logs.NewLogs.zip

[Carl Morris]

but if your insinuating that the P2AAF code is related to the LPFP i have to disagree.

All I know is that I've had that code before and since they replaced the LP sensor I haven't had it any more. What does it normally indicate?