Anyone any experience of a D-Jetronic Fuel Injection

[Skyedriver]

Car, Volvo 1800 ES, rough running, ignition seems sound, remove supply pipe to the fuel rail and turn on ignition, there's a 1.5 - 2.0 spurt of fuel then nothing. Relay clicks on and off again. Should it not be a continuous flow of fuel to the fuel rail?
Thanks

[finlo]

Skyedriver said:

Car, Volvo 1800 ES, rough running, ignition seems sound, remove supply pipe to the fuel rail and turn on ignition, there's a 1.5 - 2.0 spurt of fuel then nothing. Relay clicks on and off again. Should it not be a continuous flow of fuel to the fuel rail?
Thanks

Might be a safety thing that only pumps while cranking or running?

[GreenV8S]

Skyedriver said:

Should it not be a continuous flow of fuel to the fuel rail?

It's very common for fuel pumps to run a brief priming pulse when the ignition is switched on, and then only run while the engine is turning.

[Richard-D]

That sounds correct to me. EFI cars run the pump to ensure fuel pressure but it doesn't run indefinitely unless the ECU sees a signal from the crank sensor.

I don't know specifically for your car (and I'm sure there will be an oddity somewhere) but that would be exactly what I expect to see with the key on/rail supply disconnected.

[E-bmw]

As above the pump just primes the system for a few seconds when initially turning on & then properly when actually starting.

ETA.
You say rough running, what have you tried/checked/tested?

Fuel pump certainly wouldn't be anywhere near the top of the list generically.

[paul_c123]

I had a 1970s Merc with D-Jetronic.

[Skyedriver]

Having spent a while googling (more successfully than getting the car started) yes a 2 second burst to prime the line.
Gauge on the supply hose to the rail reads 60psi, regulator should knock that down to 30psi
I have decent spark at the plugs.
All I can think of is ither the injectors aren't injecting and they were when the car was used two weeks previous or the cylinders have been flooded somehow when starting but that's never happened before. Had the car about 4 or 5 months, done around 800miles.
Thinking out aloud, I haven't checked ignition timing but I haven't moved the distributor, just taken the cap off and checked the breaker points. And that was after it died.