Still try taking it apart. It normally is a sticky diaphragm especially if random nozzles on different sections.Have changed all diaphragms in chemsavers at beginning of year
On my ones I normally just break them where the diaphragm is take it out and put it back. Normally does the trick. Save the vas for better uses.Take the whole chemsaver apart?
They take a bit of vas too don't they to aid lubrication?
What's a chemsaver?