ATX "bucking"

[jeffdjeffd]

After B6 install, my Festiva ATX is "bucking": let me descrbe.

Above 2200 RPM with very little throttle, it will either accelerate or kickdown into engine brake mode, but not allow for a soft throttle to maintain speed/RPM. Usually starts around 38-40 mph in 3rd gear. Also seems to shift later than before - possibly related?

I'm not sure how the engine braking system works. My guess is that the problem is vacuum related, but would appreciate some starting points (Jim, Yvan???)

thanks muchly!
jeff

[yvanlavoie20]

vaccum hose

check if you have vaccum on the small hose in the front of tranny...
you should have engine vaccum to the modulator.

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