740 GLE 1988/89 Engine not Firing

Try pulling an injector out with ignition on then lift flap in metering unit and see if it sprays fuel out. If it sprays fuel out air flow meter is ok if not replace. Mike

This sounds like fuel starvation either fuel filter is blocked (replace every 60,000 miles item) or the in-tanlk pump has developed a fuel delivery problem. How much fuel is in your fuel tank? If it is less than half full you will need to take the in-tank pump out and replace the hose which will have split or thoroughly clean the sock filter fitted to the in-tank unit. The extra noise from the main fuel pump is the clue. All the best, Peter.

thanks for the info Peter; the only thing which makes us think it is not the fuel pump or some sort of fuel blockage is that when the fuel line is removed from the pressure compensator/metering unit, the said line squirts out fuel with a degree of pressure.. do you think this would still occur if there was a pump problem?

The main pump (under the floor) is a pump/reservoir unit. It is one thing for the main pump to keep up a pressure in the reservoir and hence the rest of the system (going forward to the engine) but without the support of the in-tank pump it will start to make much more noise than normal. To avoid removing the in-tank unit in the first instance, take off the petrol cap and have the ignition switched on. Listen for the in-tank pump working. Once the system loses pressure it will cut out.

:-) Fantastic Advise! Thanks very much both of you for that advise... You were correct it was a blockage in the fuel pipe which was stressing the pipe and making the noise. Looks like with the fuel line off, there was enough ommph to push fuel out (thus confusing us into thinking all was ok there) but obviously once connected to the system, the blockage was preventing the pump from being able to push the fuel through the system into the injectors.