ok I have a 2008 gsr 4800miles, with a cobb intake, sp test pipe and a 90degree exhaust dump over the axel, and a cobb ap, no wb yet...I know it's a big NO NO, so it's in the mail. I loaded up stage 2 sf anc 91 map for cali gas, and I got a tank of 91octane mixed with 100octane. I would get knock retard up to 1.8 under load and hit 2.8 under 2800rpm. So I switched to stage 2 sf 91 and it was no better. I am on stage 1 sf anc map now and I am hitting 1.4 under load and I hit 3.8 in 5th gear at about 2500rpm. I will say it's random knock not always there or the same. I swapped fuel relays with drl I think...no change. I also noticed some fluttering come from wastegate or bov...not sure. Anyways anyone else having this much of an issue with cobb ap ots maps? I thought cobb was the easy way to go....what do I do?

 

First of all it is normal. I see many X's do this that have some miles on them.. stiffer suspension, motor mounts, exhaust resonance, and of course our TOB. The knock sensor is just a microphone. The X sensor is very sensitive down low in the rpm range. It needs a high threshold.

So if you get 1.4 knock counts, then 1.4/.35 = 4 counts of knock. Which is safe.

All turbo cars knock, that's a fact. You can't tune out all the knock. It is impossible.

This is nothing you should be worried about. I say leave it alone. Enjoy your car.

 

If you read read the notes accompanying the AP OTS maps, you will notice you deviated from both S 1 and S 2. What exactly did you expect?

 

This thread is useless without logs.

Clipse3GT shouldn't be giving that advice without seeing them

2.8 = 8KS
3.85 = 11KS

Clipse3GT probably didn't see that part

 

Indeed that is some significant knock there, 1-4 counts (or .35 to 1.40 on the Cobb scale) is about as much as I would tolerate without investigating. What kind of boost is it hitting in 5th as boost comes on when it knocks? Sounds like you are running lean in that area for some reason, I would get it sorted asap and a wideband would really help shed some light on figuring it all out.

 

I had something similar to me happen as well. I had flashed the car started driving and seeing my initial impressions. I had seen anywhere from .7 knock all the way to 3.2 counts of knock.

The car needs to re-learn the fuel trims and it will settle. The LTFT and STFT are calculated %

I realized that after driving around for 50 miles or so and did another data log I was getting a max of 0.7 of Knock under heavy boosting.

I think especially that you are flashing between multiple maps and not letting the car settle is not helping any.

 

+1

Without 3 good WOT logs in 3rd or 4th nobody can really help you out. Even 1 log would help some.

 

Don't hold me to this but if I remember right just by flashing to map or switching does not reset your LTFT. Taking the - side off the battery it will.

 

The AP will reset all learned parameters after a re-flash. On a side note, the COBB OTS maps are not tuned with "test-pipes"; only TBE with HFC.

 

A good suggestion to the op is if he is not planning on tuning in ATR he should just skip the headache and get it professionally tuned. The cobb OTS maps are great starting points when you deviate from the designated mods you need to make the proper changes.

 

This is from another thread about LTFT with the AP. Im Ecuflash guy so don't hold me to it.

Your car is warm, your new map is loaded, you have made sure that you can connect with ATR and you have selected all the correct parameters to log. Good now unhook the positive side of your battery so you can reset your ECU. This is to make sure that all save long term fuel trims are wiped clean from the memory so your logs aren’t contaminated for tuning. Once the positive terminal is disconnected hold your brake pedal down for about a minute then let the car sit for about 10 minutes. When this is done and you reconnect your battery your clock should say 1:00 and all your preset radio stations should be gone. If not disconnect again and add a few minutes.

 

COBB AP can reset the learned LTFT's with the reset function no needed to disconnect ECU/Battery.

 

I think you are making too much of deal about this... these cars knock in lower rpms, while in closed loop, on a stock timing map, with no mods. So it does not surprise me that his is knocking in lower rpms...

There is probably nothing to worry about...

 

Yes, I also get the knock at lower rpm's (typically 1000-2000 rpm's), but only when leaving from a complete stop and at very low load. I believe it's the throwout bearing as someone alluded to.

However, it appears he is getting knock even in fifth gear. It's possible he is overboosting or running lean, so it would be useful to see a log. Also, it's important to see if it's happening at low load (< 100) or higher load.

 

I know my car makes 25psi at around 2800 rpm so I would be a little concerned with the knock.