A3 engine problem??


Wrench Pro
A3 1.8 T sport
hi, i have a 1998 1.8T A3, when i lift off the throttle the car seems to jerke forward as if im pressing the break, aslo sometimes in third gear the turbo seems to hesitate when accelerating then kicks in after about 4-5 seconds? i have fitted forge split r dump valve and pipercross viper induction kit. i have also replaced the MAS and the temp. sensor, but has not helped can any one help?
take off the splitter valve and refit the standard DV. see if that helps
or full close the spliiter valve
when you said MAS did you mean MAF ?
if its nether of these id start looking for split vacum pipes.

have you ran a diagnositc on it ?
the car came with a forge dump valve when i bought it but i upgraded to the splitter i will try closing the valve fully.(wouldnt that remove the noise) it is 20 clicks clockwise at the mo,

yes i did mean MAF sorry, i will look fully to see if if i have a split in vavum pipe, :)

i put the car on a rolling road and engine fault code check and it didnt come up with anything
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yes closing it would remove the noise, but as the ECU runs it in closed loop it looking for the air. with the valve open at all some of this air is being put to the atmosphere.

might also be worth taking off the throttle body and cleaning it out with carb / electronic cleaner. should beeasy enough on the 98 as it will still be cable operated.
have you recently cleaned the air filter ? if so did you re-oil it ? could be that the oil has contaminated the MAF causing it to give lower readings.
An induction kit will take about 300 miles for the engine to get fully used to. Have you added this recently?
It should have settled in then. It would be worth just putting the standard airbox back on to see if that is where the fault lies.

It is possible that you need to upgrade the exhaust to balance the flow of air through the engine. A few of our members noted a flat spot until they added a sports exhaust to their induction kits.

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