4rdkillr

I recently purchased a 2001 Z28 W/LS1. The car is equiped with the SLP 40 hp kit (cold air ind. and cat back). The car was taken to the local drag strip and run several passes time only. After manually unlocking the traction control the car launches beautifully only to fall on its face at the 1-2 shift. The traction control which should be off takes control of the throttle and I have to get completely off the throttle and back in it to resume full throttle acceleration. I do not understand why it would only limit the tire slippage on the 1-2 upshift. When the tires break loose on the launch and during the 2-3 upshift it works fine. The car ran 13.82 even with losing at least a full second trying to recover from this annoyance. Any one else have this problem? Any advice from you guys/gals would be helpful.........Thanx

Frost

iTrader: (45)

torque management if TCS is switched off..

4rdkillr

Torque management? It is my understanding that the tcs senses wheel slippage by way of the abs sensors. When slippage occurs the engine management system retards the timing thereby effectively removing any throttle response to stop the tires from slipping. It only does this when turned OFF during the tire chirp of the first to second gear shift. The tires "break loose" on launch and during the 2-3 shift with no reaction from the tcs. My question is with the system tunrned OFF, why would the car choose to turn the system on only for the 1-2 upshift?

RZRSEDGE

iTrader: (21)

As stated, torque management. It also pulls timing. Instead of traction, it pulls timing to take it easy on the drive train.

4rdkillr

So how do I stop the theft of my motor at the track? Or can I. Does everyone have this problem. Can I stop this from happening or am I just SOL

2xLS1

iTrader: (25)

Are you sure it's not just hitting the rev limiter on the 1-2 shift? If TC is turned off with the ASR switch, it is off all the time and the ASR off light will be illuminated on the dash. Some of your terminology is strange. What do you mean by manually unlocking the traction control.

4rdkillr

sorry my dad posted up the first post for me he was a little sketchy on his terms. I turn it off by pressing the button. And I thought it might be the rev limiter too but then why wouldn't it do it on the 2-3 shift? didn't make sense to me. The first time it happend I thought the tranny was slipping until I realised that it had broke the tires loose. I have only had it to the track once because of this frustration so I haven't tried making it shift at a different rpm to see if it is a rev limiter. Assuming it has a stock tune what would the rev limiter be set at?

Shallow Bay

iTrader: (3)

6200 RPMs

2xLS1

iTrader: (25)

The motor is reving faster in first gear so the tranns has less time to complete the shift after the rpm and mph shift thresholds in the PCM are passed and it commands the shift. Slower reving in second gives the trand more time to complete the shift before the rev limiter is reached. Make sure the trans fluid is not low. What do you have the gear selector in when running at the track?

4rdkillr

Well I just drop it into drive for now cause obviously it would hurt to put it in overdrive and I would shift it myself if not for the slip up between first and second. The trans fluid is fine I checked it before I went to the track and after as with all the other fluids. I think it would run high 12's without this happening so it is very frustrating

2xLS1

iTrader: (25)

Try running it in OD. It won't hurt anything. Don't shift it manually either. Still the stock converter or higher stall?

Z ROADSTER

Don't attempt to manually shift starting in low gear. My 02 did the same thing but only when I start off in low range and shift manually. Just put the damn thing in overdrive & leave it there.
Your times will NOT be any quicker shifting an automatic manually & could possibly be detrimental to the life of your trans.

4rdkillr

As far as I know it still has a factory converter, however I really have no idea what has been done to this car other than the slp intake and exhaust, the owner before me didn't do anything to it either so whoever had it before them did everything to it and I don't know who that is. So you why would my running it in overdrive solve my problem?

4rdkillr

Well I still don't know what the problem is but I I went to the track last night unexpectedly and let out about 5500 rpm let it shift and got back on it. Did it three times first pass was 13.93 at 105.63, second was 13.93 at 103.19 with my gf in the car, and third was 13.60 at 104.26

Z ROADSTER

Did you put it in drive or O/D & not hot brake it at the line , just nail it on the last yellow ? Your MPH is good for low 13's . If you did the above it should shift itself at about 6200 RPM thru first-second-& third gear crossing the line . But your MPH is lookin good.

jimmyblue

iTrader: (11)

If traction control is off, then it's off. It won't kick the pedal.

You may have some knock problem leading to a big spark
pullout when the motor hauls down after the shift, in
addition to torque management's "contribution". TM is a
"hard hole" that's overwith soon after; knock retard is a
"sand trap" that you crawl back out of slowly. You would
want to be logging the spark retard and spark advance
to see.

Knock retard can be air/fuel related, or it can be false
like exhaust banging; banging is worst in 1st because the
gear reduction of the trans rolls the motor more on its
mounts, as back-torque.

RUTAN TA

Does it have a TPS sensor code in the PCM?

4rdkillr

I don't know if it is showing any codes I have nothing to read them with, and I suppose it could be a knock but wouldn't that be noticeable? I am going to buy a tuner within the next few weeks, and I also plan on taking it to Tracy's to get the diagnostic and have them see if any codes are showing. Also understand that I am running at wichita international those of you who have been there no what I'm talkin about, for those that haven't its a little slick. No I don't just punch it at the line I stall it up and launch somewhere around 1200 but no matter what I do it spins through the 60 ft. Its not shifting at 6200 its shifting when I let out at 5500

Frost

iTrader: (45)

if it's shifting at 5200 when you "let out" I don't see what the problem is?

4rdkillr

The problem is that I have an inconsistant car if I have to let out wait for it to shift and then get back in it