2002 Lupo 1.4 16v (BBY)hiive a misfire on my girlfriends Lupo that I cannot get to the bottom of.it starts fine, and idles fire but one warm when driving when it's not under load it's misfires/hunts quite badly on partial throttle.its had a full service, throttle body cleaned and reset on VCDS, new coil packs and sparkplugs and all vacumn pipes checked.also replaced a leaking section of exhaust.A scan showed up 17961 Barometric/Manifold Pressure SignalsP1553 - 35-10 - implausible Correlation - intermittentThis was cleared and hasn't returned, yet the misfire is quickly getting worse.
Done a compression test this morning, and got an almost identical 250 PSI off 3 cylinders, after repeating the test many times; but the cylinder next to the cambelt only managed 225 PSI after testing time and time again.any suggestions what I can check? (I've got VCDS)