Hi, newbie here. My 89 Jetta GLI has been stalling lately when the engine's cold. I've replaced the fuel filter and the mini filter. Replaced the fuel line from the filter to the gas distributor as my old line had a leak in it and have run fuel cleaner through it. The problem started after I replaced the line. I'm thinking that there may have been some very small debris in it even though I could blow through it well because it was used. But I've decided that it's probably the cold start valve going out or something since it only happens when the engine is cold. Please enlighten me on this.