vauxhall ecotec engine with poor vacuum

X14XE in 1997 Astra F

Engine very sluggish, vacuum is 9" at normal idle; should be 18 - 22"; compressions are all OK; brakes are crap because of insufficient vacuum. Have checked for leaks from the easy-to-treach hoses.

Is this a known problem with these engines?

diesel

I don't know if it's a known problem with these engines but you must have a leak as you suggest. Look to the servo unit,the diaphragm could be holed.Try clamping the pipe to the unit and see if engine tickover improves,if it does change the servo unit.

if its low and steady your looking at vacuum leaks or incorrect valve timing

Get a tin of WD40 spray around the inlet manifold, particulary near to where the manifold meets the head.

X14XE's are prone for the inlet manifold gaskets bridging. If your engine revs increase while you are spraying WD then its drawing air.

Is the engine running a bit lumpy ? this will also point to the gasket.

Have you replaced the pollen filter recently ? There is a vac pipe running near the pollen filter that operates the recirculation switch inside the car. These are easily disturbed if replacing the pollen filter.

Have a good spray around pipes and unions with the wd, Good luck.