goofygrin

iTrader: (5)

OK, so the DTC disable stuff has been out for a while and I am VERY hesitant to disable any of the airflow check DTCs (P123x).

In talking to Cobb (who's base maps have the DTCs disabled by default), they recommend that you DON'T disable them on custom maps; however they were getting beat up by people running their staged maps throwing the codes, so they turned them off by default.

I personally think that these checks are there to protect your car from big spikes in boost that can damage the motor. Disabling them is dangerous IMO.

So what do you think?

Clipse3GT

iTrader: (10)

If your car is tuned properly and the boost limit and timer are set up correctly. Your car will be protected from overboosting. The torque limit/ airflow maps will limit making power if left stock.

What are you using to tune?

I have my turned off for sometime now, but I my car tuned properly as well.

goofygrin

iTrader: (5)

if your car is tuned correctly, why disable the DTCs? They should never fire, right?

Clipse3GT

iTrader: (10)

Well the only time this wasn't the case is with a aftermarket BOV.

It will throw a limp mode with some... thus far I know it will throw a limit mode with:

Forge RS
HKS SSQV
GFB Stealth FX (least of the 3)

LaXGSR

goofygrin, I am in the same boat. I am very hesitant to disable those DTC's. I did hit P1235 once in 35 degree weather. I then re-logged and adjusted by BTEL as well as airflow limit tables (<15%), and haven't hit it since (in the same or colder weather).

I agree that if tuned properly, it's probably safer to just adjust the limits in the tables rather than disabling the codes completely. I'm very conservative though.

murlo26

iTrader: (9)

Well the good news is that if you boost spike or hit too high of load with them disabled you still get this if you airflow limits aren't dialed in.



I would turn them off so you don't have to deal with limp mode assuming you trust your tuner. Otherwise if you are tuned right, I think you are correct to assume you shouldn't see them unless you spike from weather or another factor in which case they are doing their job.

Hiboost

iTrader: (9)

I adjusted mine perfectly but there was always that slight chance with the right airflow combination that at low RPM's just as the turbo was spooling that it would trigger a limp mode if the stars aligned poorly. So while my WOT operation was dead on perfect the parts of the table where the boost threshold was kicking in would be tricky under different conditions.

The last straw was running limp mode in the finals at the '09 Buschur Shootout and I ended up running at 30% throttle the entire quarter mile. What's ironic is that the my competitor was having the stationary launch triggering the same limp modes all day while I wasn't until the last round. Lucky for me and really unlucky for the guy I was racing in the finals he did a 1-2-1 shift and was out of the race completely.

Even though I won I was pissed since all day I couldn't do better than a 12.0 @ 119 mph in the 90* F track temps. I was either bogging off the line or getting mad wheel hop with tires spinning, nothing in betwee. After the disable code I never get a stupid limp mode from doing a stationary launch and I will never go back after what I went through trying to eliminate it!

LVSBB6

iTrader: (4)

Just turn it off if your car is tuned properly. No point to having the chance of runing into limp mode.

RogueValley

Agreed, you're tuner should be more then compitent. If you didn't trust them on your car, you should have been tuned elsewhere. A tune from someone who works on your car that long to make sure your part throttle airflows are spot on deserve more then you probably paid them.

Just get them disabled. How many cars come with this feature and how many of them seem to be doing just fine without it?

goofygrin

iTrader: (5)

the logic you guys are displaying makes NO SENSE.

If your tuner is competent and your tune is correct, then YOU SHOULD NEVER HIT THESE PROTECTIVE DTCs, so there should be no need to disable them.

That's my opinion.

Clipse3GT

iTrader: (10)

Just leave them on.

Call it day, we will just go in circles.

murlo26

iTrader: (9)

Pretty much what I said, I agree, if they are dialed in for sure leave them on. If you tuner is having trouble and you just can't get them dialed up, then disable them.

Hiboost

iTrader: (9)

I'm not sure I follow the blanket statements you are making here condemning disabling the DTC codes so I'll explain my position again in more detail so that It makes more sense.

I've tried just about every combination of increasing or decreasing values on the airflow and torque limits tables to avoid the stationary rev limiter triggering limp modes. For daily driving they worked 99% as good as they could and initially wanted to avoid using the disable codes, but rev the car at the stationary limiter and only build 8 psi at 6k with 100% throttle versus 27+ psi at 6k with 100% throttle while moving 95 mph in 4th gear and you can see that trying to match expected airflow curves to avoid limp mode with these two extremes isn't going to be easy. As soon as I upped boost to 30 psi on 100 unleaded I needed to increase the limits higher, but that caused the stationary limiter launches to trigger a "low airflow DTC" every time. Unless someone has detailed how each of the three airflow and torque limits tables comes into play without me noticing, there was simply no other way to accomodate my setup without keeping the values lower and limiting boost levels and that's no fun.

I still have boost limit tables set so that if my load percent stays consistantly 20% higher for longer than 1 second it shuts down the party. The DTC airflow codes triggering the car to fall on it's face when detecting "not enough airflow" were extremely annoying and I fail to see how not running enough boost at 2000 rpm is going to cause such harm to your car that it has to limit you to 30% throttle. In fact I'm quite sure that if my internal WG failed without the DTC disable code in place I would have been stuck driving in perma limp mode until I got everything replaced which would have made the car completely undriveable.

At some point you have to accept that the tables they gave us will NOT allow you to accomodate all extremes of airflow levels without causing problems. Specifically the stationary limiter airflow versus WOT in 4th gear airflow being so drastically different yet using the same table based on TPS.

You can't expect people to take you seriously if you open a thread labeled "Discuss: Disabling DTCs Yes or No" and then refuse to listen to any discussions.

I support keeping the limits tables active if possible but in my situation I'll be damned if someone is going to label me as incompetant for using the disable codes when I spent countless hours and reflashes to my ECU in order to work around my particular issue before throwing in the towel.

goofygrin

iTrader: (5)

My issue isn't with discussion. My issue is that people say "get a good tune and then disable" -- which makes no sense.

It seems to me that for MOST people disabling the checks is simply a shortcut.

Your case is likely a fringe case and I'm interested to see if there are other people that have taken the time to determine if they need to disable them or if they just jump to disable.

My concern is that by disabling these codes, simply to make life easier, I'm going to blow my motor due to prolonged "overboost" conditions.

Optiblue

iTrader: (5)

I'm running stage 1 maps and if both cobb and perrin say it's okay to have it off, I'm not arguing~