Verified VCDS User
- Sep 14, 2016
- Reaction score
- VCDS Serial number
Thank you for this. I replaced the N80 and thought I might have resolved the issue but after 500miles, I just had the same issue. One thing to note, it seems to happen often when the ambient air temperature is hot. I can't recollect any times it has happened when it has not been in the hot sun, predominantly after having just driven it. That could be a coincidence but would that lend any one way over another? Planning my next course of action...Hi,
I understand that the is a intermittent problem, engine can be hard to start, one fault code that was displayed was not for day of incident?
The above N80 valve has already been discussed.
Check Air mass meter, if this fails, this will have affect on ECMs mapping of fuel air mixture, causing lean/rich, is it visually contaminated, if so clean and test again. This can also be funtionally checked with vagcom or Oscilloscope.
Using Vagcom you can monitor the rail pressure, compare pressure against time taken from start of cranking to engine start. If pressure takes time to build, could be fuel pump issue or seeping injector(s), however if pressure gets up quite fast it is getting interesting.
Either with Vagcom or an oscilloscope connected to rail pressure sender might tell you better with respect to time for pressure build up, use caution and drain pressure from rail, test again. Measure time it takes from start of crank to pressure has built up in rail.
Remember also that this engine has a control valve on camshaft, item 13 in link
for variable timing, if this control valve acts up, engine can be hard to start. Using an oscilloscope for checking timing, measuring camshaft sensor and crankshaft sensor, this can tell you wether there is a longer gap between camshaft and crankshaft. If longer when engine takes a lot of cranking, suspect VVT control issue.