Brake snip issue

[Christopher Léger]

I just did the brake snip and seems to work i could get it to 3500 rpm... i did not luanch it but just tested it...

I now have an issue where when i put it on D it feels like the tranny is giving the car a jerk on start off even without fuel.. i tried putting R, then N and D and still giving me a jerk... i will see if it does it every time i leave a stop or red light, and also on R... but im a little concerned about it

 

[Christopher Léger]

I suppose its the transmition but could be something else like driveshaft or anything related to make all 4 wheels start rolling (i know nothing about mecanics)... maybe rwd is delayed possible....

 

[Helo58]

A few questions...
1) How long did you hold your car at 3500 rpm while brake boosting?
2) How many times total did you perform this "maneuver?"
3) How many miles are on your car currently?

 

[MIGULZZ]

also this may sound dumb but I must ask, did you add a switch? or just snip the wire.

 

[Christopher Léger]

A few questions...
1) How long did you hold your car at 3500 rpm while brake boosting?
2) How many times total did you perform this "maneuver?"
3) How many miles are on your car currently?

1. I held it total 4-6 secondes.. it goes upto 2800 then 2500 goes up to 3k and then 3500 and let go at that stage...

2.Tries it twice... the 2nd time i help the 3500 an additional second and i think my speed gauge started going up to 12 mph even if i was standing still..

3. My car is at 18k miles, waited 12k before any mods on car and been running map 2 for last 1k miles

also this may sound dumb but I must ask, did you add a switch? or just snip the wire.

Added a switch to correct wires, everything is well sealed up, no wires touching anything else - clean setup.


I would like to add i feel it going D to N just a tad, and i feel a high vibration from the rear going N to D. It only does this N -> D not moving and doesnt do it after stopping on stops/lights. Same effect is going on weather im on Eco or Sport

 

[washguy]

RUT ROE ! The problem is you got it up but didn't launch....you teaser you ! Wash

 

[Christopher Léger]

RUT ROE ! The problem is you got it up but didn't launch....you teaser you ! Wash

Saving it for the track lol... was at a buddy house and that road is bumpy as hell, didnt want to improvise something on the road...

 

[Christopher Léger]

View attachment 27620 its prolly hard to see by pictures but the wheel moves foward with a minor rotation (5°-10° maybe) sorry says my 13 sec video too big to upload...
If ya'll say its nothing too serious i could live with it, just dont wanna being into dealership for nothingView attachment 27621

 

[brancky3]

Does it happen with the switch in either position?

 

[Christopher Léger]

Does it happen with the switch in either position?

Yes with both on and off.. but haven't tried to do another test launch control with it on back to stock.

1st-2nd attempt switch was on tried twice for normal 2200 - 2500 rpm launch.

3rd attempt switch was off got it to 3500 rpm.

4th attempt switch off got it to 3500 rpm and held 1 second more and speedometre started going up standing still.

Accidently drove 5 miles with switch off but the symptom was already present. Turned the switch back on to stock and its still there.

 

[Christopher Léger]

Anyone suggest trying another launch control with switch on to see if seitch working properly? It was working before i switched it off

 

[Helo58]

A piece of mind check would be checking the transmission fluid level and transmission magnets for metal particles. You could also have a faulty speed sensor that might cause irregular engagement. I have no way of knowing, these are just some ideas. This might be unrelated to your wire snip.

 

[ZyroXZ2]

I don't know that I can shed proper light on this, as I've never had to snip a brake pedal sensor (and funnily enough this thread shows up as I've been looking it up learning I can't do burnouts in the Stinger to clean the tires off for a drag strip run, thus making a trip to the drag strip not at all worth it until I can).

BUT, I've noticed when I'm parking that if I am barely touching the brake to hold the car in place and put it in Park, sometimes my car SLAMS into Park in a very jarring way. The whole car feels like I got rear-ended and slams forward a few inches. I've noticed that as long as I have the brake pedal depressed a little harder, it never happens at all. I've found similar analogous behaviors with my early attempts to clean my tires off: if I am barely on the brake pedal, my RPMs actually shoot up really quick, but the moment I press the brake down to hold the car, the RPMs drop to about 1.5k, and then upon holding the brake harder, up to 2k RPMs which is the max holding point the ECU/TCU allows (including launch control).

Short story shorter: I think that the brake pedal sensor affects more things than just standing RPM... You might have adversely affected something else by snipping it. Granted, you spliced in a switch, so maybe you need to reset the car (disconnect the battery).

 

[Adamdan]

Stingers have two different shifters. One is drive my wire. I wonder if that would cause any issues.

 

[Christopher Léger]

This shows how much i know about cars... is the transmission oil somewhere under the hood or directly under the car?

Thanks for enlighting other possibilities, i will try disconnect and reconnect the baterry since i dont even have a code ...

Ive tried another launch control and the switch is ok. Its on and LC blocking off at 2200 rpm

 

[Christopher Léger]

I do know what your talking about that jerk on P, i know mine did it also but the N -> P is much more powerfull than that little jerk

 

[ZyroXZ2]

This shows how much i know about cars... is the transmission oil somewhere under the hood or directly under the car?

Thanks for enlighting other possibilities, i will try disconnect and reconnect the baterry since i dont even have a code ...

Ive tried another launch control and the switch is ok. Its on and LC blocking off at 2200 rpm

You don't have to have a code for a power cycle to reset certain systems in the car. I always do it if I feel something is way off or seems "learned" a little funny. The Stinger is just an extra PITA because I have to remove the spare to get to the battery.

 

[Helo58]

This shows how much i know about cars... is the transmission oil somewhere under the hood or directly under the car?

The unit in the Stinger is a "sealed" unit. Checking the level is done using a certain procedure with the trans at a certain temperature.

 

[StungBlueGT2]

Did you write Terry about it here or on the N54 Kia thread? Since he created the mod I assume he would be able to help you more than most.

 

[RandallK]

These mods including the JB4 are do it at your own risk .. this holds true with anything we fo to our cars from any manufacturer..

Did you write Terry about it here or on the N54 Kia thread? Since he created the mod I assume he would be able to help you more than most.