smarty & accelerator = disagreement

[CBrabec]

I have the "Wild" version that came with my smarty. Today I downloaded SW #9 to see what it had. My truck took off like a bullet but the thing that scared me was when I took my foot off the accelerator my truck keep going. I applied the brake and it wouldn't stop. I had to put into neutral to actually slow down, then my brakes worked. Has anyone else experienced this? Why would it do it?



I've run the smarty on many other settings and this didn't happen. This doesn't make me want to try #9 again. Any help would be appreciated.



Chris



P. S. My TST box was off during that run.

 

[JJPage]

There have been more than a few that have experienced the same "hanging throttle" syndrome, and not just on "wild".



I re-installed the program and it had not done it for several weeks until last weekend, then it did it while I was approaching a stop sign. I had to stand on my brakes fairly hard to stop, it just would not idle down for several seconds. I could not get it to do it again, but when you least expect it... .

 

[GOT-Torque]

I have no personal experience with this, however taking with someone about their truck it came up. He believed it was partly due to his pressure box raising the rail pressure above stock settings. The way he explained it was when he got on the throttle, rail pressure would spike and then when he got out of the throttle, it didn't drop off like normal. Kind of like the only way out for the high pressure fuel was to go thru the injectors, thus power was still being seen at the wheels for 3 seconds or so until the pressure bled off.



I could be way off base here, just what I heard... .

 

[nickleinonen]

smarty doesn't go over the max rail pressure the stock software is programed to allow. just gets there quicker

 

[DGStrate]

I have the "Wild" version that came with my smarty. Today I downloaded SW #9 to see what it had. My truck took off like a bullet but the thing that scared me was when I took my foot off the accelerator my truck keep going. I applied the brake and it wouldn't stop. I had to put into neutral to actually slow down, then my brakes worked. Has anyone else experienced this? Why would it do it?



I've run the smarty on many other settings and this didn't happen. This doesn't make me want to try #9 again. Any help would be appreciated.



Chris



P. S. My TST box was off during that run.

As others have said, not just in the wild setting... !



I have commented on other threads that I have seen/experienced the same thing on an 03 and an 05 truck, both Auto-transmission rigs... the condition has happened on the 30 and the 60 hp settings (as both those trucks are relatively stock, so were not running the high HP settings due to transmission protection)...



Bob/Marco - any thoughts on this?

 

[Bob4x4]

Stock trucks do it also... ... ... ... .



Bob

 

[DieselFiend]

I've experienced the hanging throttle with the demo smarty that Bob Wagner sent me. I asked him to address it several times over private messages but never got a response. It was pretty scary. Almost put me into the back of a couple cars on a trip I took. It was definetly a safety concern. Right now I run the mild torque management on #3 and I don't have any problem at all. I think it has something to do with all the added power and the almost non-existant torque management on your "Wild" program. I'm no expert as I'm still learning myself but maybe an after market transmission will work out better with the "wild"

 

[Bob Wagner]

Stock trucks do it also... ... ... ... .



Bob

and I think the added hp may amplify the defuel lag.



can't say for sure though

 

[CBrabec]

I think it has something to do with all the added power and the almost non-existant torque management on your "Wild" program. I'm no expert as I'm still learning myself but maybe an after market transmission will work out better with the "wild"

I have a full billet DTT, so the aftermarket transmission is covered.



So Bob, you think the extra HP may have amplified the defuel lag? Or were you referring to the stock trucks only?

 

[Giachino]

I'm going to try and artucliate this as good as i can. On my 05 (100% stock)... one time in a parking lot, i was rolling about 5mph and i juiced it... . just a quick hard stab on the throttle... . it surgrd forward and kept going for a second or so..... scared the **** out of me... . thought i was going to run something over..... I was able to replicate this again under safer circumstances.



Someone can correct me (as i am speculating), but i believe there's an ecm function (on the stock trucks) that doesnt allow instant throttle chop in order to prevent barking the turbo... . it's prevelant in the scenario above, not so much on the freeway becasue the rpm's are up and cant drop as much as in my scenario...



I'd go try to replicate on my 06, but i have a broken leg and no driving for 11 weeks! OUCH!

 

[Bertram65]

Funny how everyone is always saying how great the smarty is, then people post problems or CELs it causes and everyone replies that "oh yeah it does that"

How come no mentions any of this when they are reconmending smarty to someone who asks which box to buy?

 

[Regcabguy]

Mindless.

I've noticed in second gear in a parking lot that the rpms will not drop off completely. I think it is a built-in safeguard to save the transmission/clutch. My solution has been to downshift to 1st. This gear selection will accommodate rpm reduction to 800rpm. I wish D/C would let us stall the truck a couple of times,instead of speeding down the parking lot @ higher rpms. We'd learn by our errors and voluntarily downshift instead of the computer mandating it.

 

[ColemanR]

My truck did the same throttle hang with out the smarty scared the crap out of me the first time it. As Bob said just amplified it Love my Smarty Randy

 

[Giachino]

Funny how everyone is always saying how great the smarty is, then people post problems or CELs it causes and everyone replies that "oh yeah it does that"

How come no mentions any of this when they are reconmending smarty to someone who asks which box to buy?

In my post above, my truck was STOCK! It hasn't done it with the smarty on my 06, but it did on a 100% stock 05!... . Thats personally why i dont ever say anything bad about the smarty, because it's been awsome to me!

 

[betterthanstock]

The stock trucks do that too, if you build very high boost, it takes 2 seconds for the power to die down. It's for turbo bark.

Watch your boost gage, and if power dies when boost hits zero, put on a blowoff valve and dump the boost when you hit the brakes.



It can be a solenoid operated plastic sprinkler valve, 24 volt may work ok.

 

[JCasper]

I have heard of this before also, but I have never experienced it.



Someone I know who has a rail pressure gauge on a heavily modified truck explained it as the CP3 is pumping so hard it takes it a second or two to stop fueling. Or something like that, I would have to look up the post.

 

[DGStrate]

I think we are talking about a different thing...

All,



I think we are describing a different thing happening... Let me try to clarify what I experienced, as I have seen both of the situations being described here...



#1 - Stock OR with SMARTY (03 and 05, both Auto transmission rigs)

When you stab the throttle and then back off the accelerator quickly, the common rail pressure surges and as mentioned, there is a "lag" for the pressure to decrease (whether it is for rail pressure, turbo bark, etc - doesn't matter)... Yes, the truck seems to hang a bit on the throttle, but there is a very marked decline in the rate of acceleration as the common rail pressure drops. This happens for a couple quick seconds after a throttle stab/release... I agree that this is just a function of the ECM and may be amplified by the additional power of SMARTY. I think Merrick has also noted this "slow rail pressure backdown" lag in another couple threads, as this behavior is drastically different than on a 12 valve where you chop the throttle and the truck immediately stops directional momentum



#2 - ONLY experienced with SMARTY (03 and 05, both Auto transmission rigs)

When I have grabbed some quick, heavy throttle and then chopped the pedal, the truck seems to be "stuck" at a higher rpm than idle. It also seems that the motor runs slightly rough during this time (almost a surging type of feeling, but both trucks have stock turbos). Truck has done this both when in lock-up TC mode (O/D) and when not in lock-up mode (under 45 mph). Truck seems to "idle" at about 1200rpms or so and will actually "propel" you down the road. If you stab/left off the throttle again, sometimes it goes away. If you apply the service brakes, the truck will actually work against them and attempt to maintain whatever speed the increased rpm translates to in the gear the truck is in at that time. Once - on an empty road, the throttle "hang" occurred and since there was no one in front of me, I decided to just let it go and see what happened... 1/4 to 1/3 mile down the road it was still bumbling along, so I had to press/release the throttle pedal a couple times to get it to "realize" that there was no throttle input, so it should return to idle.



As mentioned, this has happened on the 30hp and 60hp settings, both with timing. It darn near caused me to run over a car once in rush hour traffic! It is definitely a different feeling than the rail pressure slow bleed off that the stock truck does...



Anyone else have some to add to this? Have you experienced the same thing? Different thing?



I understand the anti-stall feature in the sticks - don't agree with it, but understand how it works... Why an Auto truck would do something like this is beyond me...



Bob/Marco - please let me know if you need more details or if I did not explain the way it happens adequately... This has scared me a couple times and would be very high on my "please fix it" list! The SMARTY is a great product, just needs a few little more fine tuning...



Thanks!

-DG

 

[JJPage]

Definitely #2

 

[RMalone]

DGStrate, gives the best description of this phenomenon that I have seen. I too have noticec that a quick stab on the throttle is the best way to get the throttle to "let go", for me it has always worked. I have only noticed the "thottle hang" when I let off the throttle as the truck shifts from 3 to 4 and/or ease into the 3 to 4 shift, right at the shift the truck hangs the thottle and as stated it sort of surges or bucks. I have seen it with the 307b programming that came on my Smarty and every programming I have tried in the 309b group. It happens to me at least every other day and frankly given the number of threads and posts on the matter, Mads should fix this issue YESTERDAY!! The Smarty has tons of potential, but just wait until this issue causes a major accident, can you say "prohibitive legislation".

 

[betterthanstock]

but just wait until this issue causes a major accident, can you say "prohibitive legislation".

Ha! Are you kidding? All performance enhancing devices are illegal devices that can legally only be used on private property, not on a public road. They all come with disclaimers, and their makers disappear overnight in case of a big lawsuit, leaving you no way to collect anything.

It's like suing the neighborhood drug dealer for you wreck:-laf



By the way, the victim of your runaway truck can sue you for running an off-road device on a public road.