Slow Warm Up Issues So some people are reporting very slow warm-ups on the 1.4 tfsi engine; that's something that typically doesn't affect a good 1.4 TSI or TFSi engine. There are aluminum blocks; they're quite small; they're very efficiently designed; and to meet emissions regulations, they are specifically designed to warm up quickly. Problem: the car runs rich, and can't pass emissions test. Engine runs ok on petrol, but runs a little bit rough on cng. Still, the same condition both fuels. There is no check engine light or dtc's stored. Checked with vcds and odis. Things that I have done. 1. New sparkplugs and ignition coils, checked the wiring also --> ok 2. It spins freely, is extremely quiet at idle, or with the standard stop-start on it restarts with noticeably less rattling and shuddering than a diesel motor will produce. 18Nhp0w.

passat 1.4 tsi ecofuel problem