rough/missing slightly when i blip the throttle...

[whit]

when the car is idling and i lightly blip the throttle it's very rough as it's it's missing slightly. it's only for an instant and if you rev up to say 1.5k revs or above it's fine or if you lift off it returns to idle and is ok.

it's just that initial touch of the accelerator...what's the likely cause??

 it wouldn't be the battery would it as it has coincided with difficultly starting it after not using it for 3 days??

[rubjonny]

what engine

[whit]

what engine

2.0 8v AGG

[rubjonny]

what have you done already? id start with the usual suspects, plugs leads cap and arm, check timing etc. put it on vag-com, ecu and pump relays worth a look as is ecu temp sensor. coil common fails on these, maf prob worth a look too

[Christo77]

Sorry to jump in.. Just to say mine does the same thing,  i've nothing left to fix as i've tended to every suspect area and all the common faults over the last couple of yesrs.
It doesn't affect normal driving at all but just a little annoying if you happen to blip the throttle in abrupt fashion it coughs slightly.. still, any new suggestions welcome..

[whit]

well after letting the engine run for 10mins this morning (when it was doing this), i've just been out to see if it would start, i was hopeful as battery was still reading 12.65v. and sure thing it fired up straight away not only that but it was no longer doing the above when blipping the throttle slightly.....strange???

leaving it to run for 10mins to boost the battery back up a little i noticed i could see a very slight flicker of the odd tiny spark from the HT lead on the dizzy so i guess this warrants further investigation even though its appear to be running ok now....

[rubjonny]

yeah you'll be needing a new set of leads + cap & arm

[whit]

yeah you'll be needing a new set of leads + cap & arm

wouldn't just a new lead suffice?

anyway seems to be running ok for now?!?! well apart from the usual 50% non start due to dodgy ignition switch!!! LOL

pretty sure the cut-out and trouble re-starting is my battery is on the way out because i hadn't used it for a few days. well it is nearly 7 years old so it's done well!!!

[rubjonny]

have you seen the price of a cap and an arm? not worth messing about
http://www.vwspares.co.uk