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Old 01-21-2007, 12:46 PM   #1
Scooby Specialist
Member#: 88676
Join Date: Jun 2005
Chapter/Region: BAIC
Location: North of SCIC
Default Do Ecutek reflashes learn additional mods back to original state?

I borrowed a sticky from the Access Port section regarding mods that you can add to your cobb AP that yield little to no results because the computer learns the new modifications back to its original state. Is this true for Ecutek reflashes and custom tunes? Kinda like to know if I'm wasting my time with these mods until I tune for them.

Below are a list of things you can add to your Cobb Stage X:

P&P throttle body
High flow foam or K&N type air filter
Snorkle removal or delete
Silicone intercooler hoses
Silicone turbo inlet
TGV deletes (you'll need a fix for the CEL if applicable)
P&P exhaust manifold
Lightweight Pulley
Bigger TMIC
FMIC (this one is kinda shakey as results are a mixed bag, not sure if the FMIC or the associated intake is/was to blame)
Walbro fuel pump
One step colder spark plugs
Catless uppipe
Deadbolt Monster P&P turbo (stage 1 or 2)
Deadbolt Monster P&P VF30/34 (stage 2.5)

Remember though....anything you add to your Cobb Stage X will more than likely NOT give you the results that others who are tuned have seen. So don't think that headers will net you 17 WHP because that's what the manufacturer has on their website. So it's fine to add the mods now and not realize the mods' full potential or add the mods now knowing that soon after you will be getting a custom tune for the full benefits.

Cobb's mapping still uses the OEM computer's learning function. This means when you add something new and a parameter changes, you may see some differences either "good" or "bad", but after the learning process of the computer occurs, it will settle everything back out as near to it's original state as it can.
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Old 01-21-2007, 07:33 PM   #2
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Member#: 7327
Join Date: Jun 2001
Chapter/Region: NWIC
Location: Seattle, WA
2008 Mazdaspeed3
2006 Wrangler Sport


Wow. So much of what you have listed I would consider to represent a SIGNIFICANT change that needs to be tuned for. Especially the header and FMIC.
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Old 01-22-2007, 01:11 AM   #3
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Join Date: Jun 2005
Chapter/Region: BAIC
Location: North of SCIC

I agree with you, but more of what I'm looking to figure out is if the computer relearns to bring it back to original map conditions or if it sees the change in air flow and allows an increase of power to occur.
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Old 01-22-2007, 02:21 AM   #4
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Join Date: Jun 2005
Chapter/Region: MWSOC
Location: Indianapolis, IN
2009 BMW 135i


Ehh, yes and no.

The ECU has its own learning maps it sets up to adjust for conditions like knock and feedback from the O2 sensors to regulate the engine operation. It constantly adjusts idle timing, fuel trims, ignition advance numbers, etc. The best examples are fuel trims and the ignition advance multiplier.

The ECU has to constantly adjust things like fueling and timing because you can't predict everything perfectly. Say, there is no humidity sensor in the car, but humidity might affect how the mass airflow sensor measures, or affect best timing. So the manufacturer can increase cost and add a new sensor to fix it, or if it isn't a very big effect, let the ECU's smarts compensate on the fly. There is a trade-off for the manufacturer here. Thus, the ECU needs to learn for anything for which it can't be tuned beforehand. With a good set of sensor data and the right compensations, it has to learn less itself. I tend to think minimizing the amount the ECU has to learn is preferred though some will argue.

When you tune the car, you can change any values in a huge number of tables.

While the ECU can learn, it cannot specifically on the technical side of things overwrite the same maps the tuner initially used to tune the car.

If looked at on a specific basis one can come up with circumstances when the ECU will "unlearn" what it was tuned it for. Like if you do nothing but add timing and you're already on the edge of knock, the ECU adjusts by lowering timing. It does NOT do this by changing the map you just added timing to, but using its own learned data maps. The result might be similar to if it had actually changed the tuner's timing map back to the lower timing value, but technically it is not the same thing. It is it's own compensation map, table, or value. This can show up when you log if you look at the right data. In this circumstance if you had a ignition advance multiplier running at 0.9 most of the time, then retuned for more timing, your IAM might just drop to 0.7 and you end up with the same timing anyway.

However, if you lowered timing way further back from stock and you were not even close to the knock threshold to begin with, the ECU can't really tell. It doesn't "go fish" on timing further than the tune allows (set by KC maps), thus it would never know to advance timing back to stock conditions. It isn't smart enough. In this circumstance it woudn't even seem to go back to stock.

There is an indirect correlation here. It depends on specifics, and what you want to nitpick over. I would agree in principle that the ECU can "unlearn" specific things in specific circumstances, but the way some of you are trying to describe it is technically incorrect. The maps that the tuner changes cannot be reverted by the ECU. A person would have to reload a backup of the original maps. You're describing a possible (not guaranteed) real world symptom, but incorrectly accounting for it. If you read the ECU back out after driving, nothing changes in the tune.
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Old 01-24-2007, 04:06 PM   #5
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Join Date: Aug 2006
Chapter/Region: Tri-State
Location: Pittsburgh, PA
2002 WRX


Originally Posted by nhluhr View Post
Wow. So much of what you have listed I would consider to represent a SIGNIFICANT change that needs to be tuned for. Especially the header and FMIC.
I must be lucky considering I've put numerous mods on my car without a tune and have had no abnormal side effects...

I've tried 3 different intakes, never any abnormal a/f's on the eugo... Never any idle problems.

I've used an atmospheric BOV and never stalled or had a rough idle, i'm sure I ran rich between shifts though.

Put a FMIC on and no changes EXCEPT for the fact that throttle response went down a slight amount, nothing noticable after ~5 minutes driving the car.

I was going to test my luck with sti pinks because they CLAIM they dont screw up your idle, but instead I'm going with 650's and a tune with my bigger turbo.
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