BlackZ28629

iTrader: (8)

I have HP tuner and it seems like the rear end is either got slack or something is wrong with tuning...when I let off the gas and coast, the car surges like... ... ... ... ... ... ... like it catches and then releases something...its so annoying..any suggestions? I have new gears and I checked it all and it looks good...Im thinking it's the tune/fuel related...

rosey

iTrader: (13)

Sounds like its in the tune. I have had similar problems with decel bucking, mostly at low rpms. Playing with the throttle cracker helped a little, but I couldn't get completely rid of it. I'm curious to hear what methods others have used successfully to cure this problem.

BlackZ28629

iTrader: (8)

so maybe lower the values in the throttle cracker airflow tables?

DaveX

Mine was almost undriveable before I spent alot of time tuning it. Get the AFR and spark right and then work on airlfow. Get your IAC counts down (under 60?) and then work on the t cracker as well as the learning tables. It adds airflow from several places and it's hard to know for sure where it is coming from so you have to be creative when logging to figure it out. I'm still learning myself.

bluehawk2

iTrader: (74)

I will have to try that with mine..........i can't stand the bucking

dmart

iTrader: (3)

I was/am having similar issues, I increased the throttle cracker tables in the low rpm regions (1600 and less) and pulled 2-4* of timing in the same area, car got about 80% better. I'm going to try pulling a little more timing today and see how she does.

BlackZ28629

iTrader: (8)

Ill have to try the same

litle88

iTrader: (20)

My tuner is also HP and mine does the exact same thing, lol I also thought there was some slack back there too! Keep us posted so I can let my tuner know!
Goodluck
Zeke

98-mongooSSe

iTrader: (2)

I have the same problem with my car, but only under 2K RPM. My tuner said that at that low of RPM, it's just a characteristic of the cam that I have (228/232/.588/.595/112LSA) & that a Camaro doesn't have throttle cracker, due to the IAC on these cars. Does that sound right?

Shay

98Z28CobraKiller

iTrader: (17)

If you look at that area of the timing table, you will see that from the factory there is over 40* in that part throttle low RPM region. On mine I had to bring the timing down to 17* in order to help smooth it out. Also, I found that running a little richer in that region helped out as well. Seems like the cams in question here are pretty small so some of you guys should double check your plugs and wires.

bluehawk2

iTrader: (74)

My cam is a 232/236 595/601 on a 112 XER lobe. I have problems cruising around at between 40 to 55 mph under lockup. The car bucks fairly bad...........sometimes I just pull it down in third.

I am hoping once I learn a lot more about using HP tuners I can fix a lot of the little issues I can't stand.

98Z28CobraKiller

iTrader: (17)

I suspect that you are at about 1800-2200 RPM correct? I would expect something like this from your cam. What I wrote above should definetly help you out.

dmart

iTrader: (3)

I have a 228/232 110 so mine has more overlap than that and I've got rid of almost all of my bucking, only thing that remains is under 1400 rpm and its very mild. And your car does have a throttle cracker table ;]

BlackZ28629

iTrader: (8)

so what g/cyl are we talkin here in the high octane table(from what to what)? What about DFCO?..throttle cracker=increase or decrease airflow in it?

Jpr5690

iTrader: (13)

I Have Found Thay My Ms3 Cam Does This Arround 40-55 Mph In 4th Gear

Aftr Playing With Some Stuff I Found That It Only Happens When The Converter Is Locked.. My Solution Was To Bump Up My Lockup Points On My Stall To 55pmh

My Tuner Said This Had To Do With Too Sharp Of A Transition In Spark Between 2 Regions I Tried Quadrouple Smoothing My Spark Table And That Although It Helped I Still Had Some Bucking (so I Just Left My Lockup Points @ 55mph To Avoid It All ToGether)

DaytonaTA

iTrader: (6)

Mine does it too, also only when the converter is locked. Tapping the brake unlocks the converter and makes the problem go away (obviously not a long term solution).

Some day I'll learn how to tune it myself and work on fixing it.

Tom
Ormond Beach, FL

BlackZ28629

iTrader: (8)

I turned the lockup off under 70MPH and it doesnt do it anymore...wish there was another way to fix it...only happens under lockup at low speeds

Jpr5690

iTrader: (13)

Again Guys From What I Was Told Its A Timeing Issue... Im Working To Resolve This Issue But I Dont See Why You Guys With Smaller Cams Are Having This Issue