Chasing Knock with the AP = Ugh.

[Parkeway]

After trying to find a map that works with my mods (Nano, Cobb Inlet, TMIC) I thought I found the answer. Alas, the car went ape with the Stage 1+SF 93 after a 50 mile break-in.

My question is this: Looking at the log, why on earth would I be seeing 5.95 KR if the A/F and Pressure were within a decent range?

I've tried map after map, and still none that suit the car (yes I'm aware that I have a Nano and not a Cobb SRI). Is this something a professional tune could fix? On second thought, maybe it's time post the ole AccessPort in the "Marketplace" forum and start tuning suspension...

*sigh*

EDIT: Sorry for the huge embed

 

[dread]

Decent A/F ratio? Your a/f is 13.38 while boosting over 21 psi. That is why you have knock, and if you keep it up you are going to blow your engine. Your fuel trims are way off. You can see the ecu is pulling 14% of the fuel, once that drops out your a/f recovers. Get access tuner race and calibrate your MAF. Otherwise get a custom tune and only use the stock map until you do.

 

[Parkeway]

Decent A/F ratio? Your a/f is 13.38 while boosting over 21 psi. That is why you have knock, and if you keep it up you are going to blow your engine. Your fuel trims are way off. You can see the ecu is pulling 14% of the fuel, once that drops out your a/f recovers. Get access tuner race and calibrate your MAF. Otherwise get a custom tune and only use the stock map until you do.

Thus the question: Why would these Stage 1 maps allow this? The only thing different about my set up is Nano and not SRI.

Does this look like a tunable situation?

 

[lzcztq]

Get access tuner race and calibrate your MAF. Otherwise get a custom tune and only use the stock map until you do.

+1
Off the shelf maps IMO are just a baseline to get you in the ballpark so fine tuning can begin.

Go to Cobb's site and submit for download to tuner race. Got mine recently. I am so enjoying learning about tuning on this car. I've only done the MAF calibration so far and fuel trims are practically spot on now.

 

[dread]

The intake is the most important mod that affects map performance. Everything in this car is based on the MAF reading, and the map is expecting a different reading than what your intake allows. In other words You are using the nano, the map is tuned for cobb's intake. Obviously the nano throws off fuel trims, as your long term fuel trims are way off, which is what is causing you to run lean and to have knock. If the intake performs consistently it can be tuned out.

 

[Parkeway]

The intake is the most important mod that affects map performance. Everything in this car is based on the MAF reading, and the map is expecting a different reading than what your intake allows. In other words You are using the nano, the map is tuned for cobb's intake. Obviously the nano throws off fuel trims, as your long term fuel trims are way off, which is what is causing you to run lean and to have knock. If the intake performs consistently it can be tuned out.

That's good to know, as the swap back to the stock map (however healthy) is excruciating!

As for the calibration, I have completed the datalog on the stock map with my mods (step 2 in the guide), however, I am unclear how to make the adjustments to the base map.

I like a good challenge, but not at the expense of a good car.

Which begs the question: What is the likelihood that those moments of knock damaged my car?

 

[dread]

Every time it happens you are causing damage, eventually the rods will give out. Use the map you were on just don't go WOT until you calibrate the MAF.

 

[COBB Tuning]

That's good to know, as the swap back to the stock map (however healthy) is excruciating!

As for the calibration, I have completed the datalog on the stock map with my mods (step 2 in the guide), however, I am unclear how to make the adjustments to the base map.

I like a good challenge, but not at the expense of a good car.

Which begs the question: What is the likelihood that those moments of knock damaged my car?

It is hard to say how much damage has occured, but as you can see the ECU did, or is doing what it was designed to do, to try and limit knock and thusly engine damage. As someone said before, the intake on these cars is king and an improper intake for your tune or tune for your intake, can cause tuning issues.

If you are unable to get a tune or do not want to mess with race tuner, reinstall the stock intake and run that with a stock intake tune. You will make more power and be happier with your car.

Travis
COBB Tuning

 

[Blendercloud]

It won't really fix the problem, but will 'treat' the symptoms... have you considered swapping out the plugs for ones that are a step colder?

I'll be doing that this weekend in an effort to get as far away from detonation as possible. You can get the Denso ITV22's much cheaper by googling them and looking for a vendor. Mine were $48 shipped from LTB Motorsports.

 

[PCspeed3]

It won't really fix the problem, but will 'treat' the symptoms... have you considered swapping out the plugs for ones that are a step colder?

Yet another temporary fix suggestion, I wouldnt take that chance if I was you. I suggest taking Cobb's advice.....

 

[Parkeway]

So the consensus is to drop the aftermarket intake and go with AP only? With the Nano, Cobb Inlet, ETS TMIC and SU race pipe, what should I remove? Only the Nano?

At this point, if that was all I was giving up, I wouldn't miss it if I could run the Stage 2 maps with reliability.

 

[derspi]

What you should really do is download AcessTuner Race then either find a good tuner to help you tune it with the mods you have or if you're confident and/or brave enough, tune it yourself.

Like someone else already mentioned, the OTS maps are just a starting point as every car will perform differently based on many variables such as climate, elevation, gas quality, air quality, etc. not to mention variability in the mods installed.

 

[Mid_Life_Crisis]

Decent A/F ratio? Your a/f is 13.38 while boosting over 21 psi. That is why you have knock, and if you keep it up you are going to blow your engine. Your fuel trims are way off. You can see the ecu is pulling 14% of the fuel, once that drops out your a/f recovers. Get access tuner race and calibrate your MAF. Otherwise get a custom tune and only use the stock map until you do.

Most people don`t seem to understand that the extra fuel is not just to make sure there is enough to burn to keep the mix from going lean. With a high pressure injection system like the ones on these engines, the fuel atomizes when it hits the cylinder, and actually absorbs ambient heat. The extra fuel, believe it or not, acts a coolant. The aiming of the injectors and the shape of the combustion chambers are designed to maximize this effect.

 

[cpolly69]

but you can't just dump limitless amounts of fuel in the mix and never get knock and i believe you will always make the best power by leaning it to be just right

 

[Mid_Life_Crisis]

but you can't just dump limitless amounts of fuel in the mix and never get knock and i believe you will always make the best power by leaning it to be just right

No one said you could. There is an ideal point that only trial and error will find. Just hope the errors aren`t the kind that spit parts out the side of your block.