Hello all,

Aforementioned '90 744GL w/224K has been off the road for about 8 weeks now. The problem began as a intermittent no start and eventually quit altogether. I replaced the Crank Sensor and Fuel Pump Relay to no avail. Eventually I got it to start by clamping the line from the Fuel Pressure Regulator back to the rail.

I replaced the Fuel Pressure Regulator and now it will start but will only idle while you give it some revs. The one time I got it running for long enough to idle on it's own the revs surged up and down and you could see the motor rocking on it's mounts(they're new!).

I suspect it's a fuel issue of some sort and I should really test the fuel pressure, to this end I borrowed a home-made tester from a colleague but I can't figure out where to attach it...the main hose at the back of the rail does not have a clamp but a graduated plastic fitting which I'm scared of breaking. Oh, I should have said, the car is Regina. I now suspect it's the pump which definitely runs but might be weak I suppose. I am loath to throw any more parts at this thing. Could the fuel filter cause symptoms like this? probably not a bad idea to replace it anyway but I want resolution here.

Any suggestions would be greatly appreciated. Otherwise I'm thinking it'll have to go to the shop and I could really do without that.