Black Smoke After Tune

[SidewinderGTS]

Used the SCT DCX Flash.Car pulls hard and runs cooler.Racing road course and people were telling me that black smoke was coming out my tail pipe. Here's a pic.

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I'm thinking rich?
Anyone else used this have the same problem?
Thanks

 

[dansauto]

yes too rich, it could be anywhere under the fuel curve, need to re-tune

 

[Casey]

"I'm rich, ******"

Well, maybe not, but your GTS is!

 

[Viper Specialty]

Likely rich in the decel fuel curve area, or pig rich on the multipliers. Conditions? Under accel? Decel? etc?

Possibly a factory map installed on a Cammed car running a processor code for a "creampuff" car?

Injectors changed and offsets all wrong?

Could be a number of things...

 

[Jack B]

Likely rich in the decel fuel curve area, or pig rich on the multipliers. Conditions? Under accel? Decel? etc?

Possibly a factory map installed on a Cammed car running a processor code for a "creampuff" car?

Injectors changed and offsets all wrong?

Could be a number of things...

The only real answer is to install a wideband or go to a dyno that has a wideband.

 

[SoCal Rebell]

Used the SCT DCX Flash.Car pulls hard and runs cooler.Racing road course and people were telling me that black smoke was coming out my tail pipe. Here's a pic.

You must be registered for see images

I'm thinking rich?
Anyone else used this have the same problem?
Thanks

That happened to me also at Willow Springs. The car runs rich to protect the motor, but the PCM should "learn" in a day or so and correct itself, at least it did on my RT/10.

 

[Viper Specialty]

The only real answer is to install a wideband or go to a dyno that has a wideband.

Not neccesarily, you could likely correct most of it with a bit of knowledge and the ability to read all of the adaptive cells. There are a lot of things the wideband wont tell you, and being a closed loop system, a lot of things will also be hidden from the wideband. The Wideband is only going to tell you where the problem lis, but it cant tell you how much of the problem is being hidden, and the root cause of the issue. The adaptives tell a bigger story for starting an investigation on this one.

For instance, if the decel fuel shutoff is not working correctly, you may assume your base tables are too rich, when in reality you just have an incorrect vacuum range.

 

[Jack B]

Not neccesarily, you could likely correct most of it with a bit of knowledge and the ability to read all of the adaptive cells. There are a lot of things the wideband wont tell you, and being a closed loop system, a lot of things will also be hidden from the wideband. The Wideband is only going to tell you where the problem lis, but it cant tell you how much of the problem is being hidden, and the root cause of the issue. The adaptives tell a bigger story for starting an investigation on this one.

For instance, if the decel fuel shutoff is not working correctly, you may assume your base tables are too rich, when in reality you just have an incorrect vacuum range.

I will wager you the issue is at WOT (open loop). A typical PCM flash is not going modify anything, but, low vacuum operation.

 

[Viper Specialty]

I will wager you the issue is at WOT (open loop). A typical PCM flash is not going modify anything, but, low vacuum operation.

When we write a flash, we alter anything and everything based on what the car has done to it (keep in mind, we have had this software since day 1 as well).

My point was that whoever wrote the tune may have overlooked a simple change that is causing this problem (such as the parameters for Decel Fuel Shutoff) as the program it started as for a baseline may have been a creampuff program. I am just saying it may be a simple oversight- but a Wideband may not show you the right info unless you can view any and all other possible changes.