I was very lucky to receive a phone call from my uncle before Christmas about a 1987 Jetta GTI that a man was selling with 83k miles, dry stored for 20 years but not started in nearly 15. I was told by the previous owners mechanic that it would only occasionally start but run very rough, and that it was definitely a fuel issue. I changed all fluids and filters before trying anything but have also checked pretty much every part of the K-jet fuel system - metering head piston moves freely, plunger looks and feels right, injectors are all spraying nicely, even measured the fuel pressure when primed ('system control' pressure?) to be 70psi. Smoke tested and no air leaks, timing is definitely spot on and I'm getting good spark at each cylinder! I'm tearing my hair out on this one after replacing the CSV and hoping that would sort it but no luck. Funny thing is when I had the CSV off and the gap into the inlet open, it started straight away and ran slightly rough until I plugged the gap with my finger and it just died straight away! The next things I plan to check is the distributor cab for timing of the spark, ECU for any damage like burning on the board and all the coolant sensors at the side of the block. I've ordered a new ECU coolant sensor but it feels like I'm stabbing in the dark here, everything seems right to get it started at least and I can suss rough running from there! Any ideas or assistance would be much appreciated!
If it has spark and you are sure it has compression, then, timing aside, spray some carb spray or brake cleaner into the manifold. If the engine pops briefly, then you have a fuel issue and can start looking at the fuel pump and so on.
