Problems--Help Please

[94 Stangg]

94 Mustang GT 5 speed I just finished a complete trick flow top end kit including heads rockers pushrods lifters cam upper and lower intake I have a novi 2000 on it and I deleted the air, smog , egr. I tried to get it tuned and dyno today and the place said i would have to address a problem with the bucking that is taking place in basically all gears when I release the gas and the car starts to slow down.. anyone have an idea

 

[Venom351R]

if they were tuning it they should have been able to cure the bucking issue and they can delete the EGR/Smog so that the ECU doe not detect it anymore

 

[94 Stangg]

They didn't want to tune it until the bucking issue was resolved. They said they did not know what was causing it. They checked timing, ignition, plugs everything seemed fine.

 

[94 Stangg]

I was thinking maybe IAC, or TPS Im not sure?

 

[Venom351R]

Not to sure, it must be excessive bucking for them not to want to tune it. It's a fairly common issue

 

[94 Stangg]

Any suggestions on what you think I may have to lookinto

 

[HISSIN50]

Any codes?

Does the IAC have any issues that you know of?

The IAC duty-cycle increases during closed-throttle deceleration, so if the IAC is acting up, it could cause issues.

 

[94 Stangg]

i was thinking maybe iac i bought a new one today and i am gonna replace it tomm. ill keep u posted
Thanks

 

[94 Stangg]

Not throwing any codes except for egr which i eliminated. At least that is what the performance shop said. Still putting in a new Iac I will keep u posted. Also i will kepp my ears open for you on that t5

 

[toyman]

Is there a chip/tuning device already in place? If there is and the fuel decel is not properly set that will cause bucking as the fuel is turned on and off.

 

[94 Stangg]

No tune/ chip Car has a paxton novi 2000 charger there is a fuel regulator and the novi came with a fcu. any ideas

 

[64post]

I had bucking real bad at low speeds in any gear except first, changed rear end gear from 3.73 to 4.10 and now the bucking is only noticible in 5th gear at low, low speed, I can live with it, the gear change only masked the problem. I had mentioned the bucking to someone at DirtyDirty racing and he told me to check for dist. wear and the dist. shaft must turn very easy or it could cause bucking?? I never did but might sometime. Good luck.