Annoying - Fitted replacement fuel rail and won't start

[dunc]

So my old rail had a small leak, replaced it today with another and now it won't start.

The rail looks identical, the two main fuel lines are definitely in the correct location as I kept the rear one connected to the pressure regulator and swapped the regulator over instead. For the front one I identified that they were the same part no. and just put the pipe into the new (s/h) regulator.

Now the car's just turning with no sign of starting, I may have had a DME relay failure at the same time (which seems a bit unlikely) but either way I've tried starting the car with the pump running with the relay bypassed and no difference. I took a plug out expecting to see it fouled but it's dry.

I can hear fluid in the rail when running the pump, or at least buzzing like fluid being pumped through.

I suspect it's coming off again but thought I'd try on here first. When I'm back at it I'm get a multimeter onto the injectors and also try to see if there's a spark or not.

Cheers,

Dunc.

 

[ChasR]

Have you disconnected an injector lead yet? See if it runs in this state .

 

[Indi9xx]

Reduce the variables, put your old fuel pressure damper onto the replacement rail, it could be that the diaphragm is ruptured in the new one and it is dumping fuel down the vacuum hose (but I would still expect it to start), or possibly there is something else at fault with it... But reducing the variables of what has changed is often the path to success.

It could also be that the injector wiring did not like being disturbed, but I would have expected something else than a total loss of starting to be the result of that, unless one of the injector wires is now shorted, which will completely upset the electronics

 

[DC911SC]

have you removed the cap and bearing at the rail end to see if there is fuel in the rail?

 

[J.C944TurboMan]

I removed the DME relay when I replaced my rail recently , then forgot I removed it and it would not start !
After I plugged the DME back in it struggled to start and then it run really ruff as if on three injectors .
I was well peaed off as they were sold as recon injectors , anyway after about 5mins or so they cleared up and so far no further issues .
It will take a while for the fuel rail to fill up again once it has been removed and drained .

 

[dunc]

Massive thanks for all the responses, I went back to it a few days later and it started [&:]

Madness, it's running fine, have used it a few times now.

Dunc.

 

[T3rra]

Could off been battery playing up ?

 

[dunc]

Was turning over fine and tried it hooked up to my big diesel too, really weird not fussed now it's working []. Is it possible to get some kind of air lock in the rail? If so is that what the end cap on the rail is for? Not seen one in a rail before.

 

[tref]

I believe it is purely for putting a gauge on to check fuel pressure... that and cracking it to check there is actually fuel getting to the fuel rail!

 

[Eldavo]

When I've had the fuel rail off it takes a while to get it started again after all you need to get the fuel the length of the car and build up sufficient pressure!

 

[dunc]

Cheers for the info tref

One thing I don't think think the problem was was leaving enough time to get fuel up there. Had the pump running with the DME bypass in for at least 15mins plus about 10mins turning over in addition to that. It shouldn't take all that long to get fuel there if everything is correct, a few mins at a very big push but remember there will already be fuel in all the lines just the rail won't have fuel in it (think the fuel pump delivers about 850cc every 30 seconds, there must be about 200cc in the rail!)

Dunc.