16v Non starter

toddao · Post by **toddao** » Sun May 06, 2012 12:48 pm

After getting all the bits back together now she won't start, doesn't even fire, just cranks over.

I've had diesels for years and even though I had some petrols in the past I don't really know anything about fuel injection systems.

The 16v had always started winter and summer over the past four years but just before I did this recent load of work she was running then stopped and wouldn't go again.

I don't have any manual for the 16v so any pointers - a sort of check list - would be much appreciated.

Thankyou

JayW · Post by **JayW** » Sun May 06, 2012 2:05 pm

The obvious place to start would be fuel. Chech she's getting it at the fuel rail (either via the schrader valve or by knocking the hose off & cranking it briefly). Fire alert

If that checks out, move to electrical. Is EVERYTHING connected? Crank sensor, amplifier, LT lead etc etc...

Next, check for spark (the old fashioned way with insulated pliers and ground the sparkplug on something earthed).

Nine times out of 10 it'll be electrical... then just report back for the next list of checks

toddao · Post by **toddao** » Sun May 06, 2012 2:22 pm

Thanks Jay. I thought that the reason it had stalled previously was that the fuel filter was blocked so I've changed that but maybe I've disturbed the pump's operation?

Where is the 'schrader valve' re the fuel supply? I noticed there are two fuel lines at the engine end - one to the rail itself and one to a mystery component at the other end of the rail. I'm still finding my way around..

Post by **mat_fenwick** » Sun May 06, 2012 2:33 pm

From memory it's on the fuel rail the injectors are connected to but you can check just by cracking open any underbonnet fuel connection. If working correctly you should get a stream of fuel straight in your eye when cranking. Mystery component probably fuel pressure regulator.

toddao · Post by **toddao** » Sun May 06, 2012 2:39 pm

I already removed the pipe to the 'fuel pressure regulator' then and cranked without any petrol coming out..

What would be the possibilities if the tank had run low and sucked crap into the fuel line - could this damage the pump? And does the pump only work upon cranking or does it prime the system immediately upon ignition? Working out a way to check its operation.

Post by **mat_fenwick** » Sun May 06, 2012 2:46 pm

My guess is the fuel pump isn't running then. Connections OK after being disturbed? One permanent earth and switched positive (via a standard 4/5 terminal relay). If you can temporarily earth pin 2 of the relay does anything change?

EDIT - missed the last bit of your reply. It's possible it could have been blocked but IMO unlikely to be a total blockage. The FP relay is earthed via pin 20 of the ECU so not simply on with the ignition. Terminals 1 and 3 should be ignition live, and terminal 5 is the feed to the FP (so could be tested with a temporary jumper wire from battery).

toddao · Post by **toddao** » Sun May 06, 2012 3:14 pm

Any clue as to where this relay might be located?

toddao · Post by **toddao** » Sun May 06, 2012 6:40 pm

I've found the pump relay - next to the ignition relay between the LHM tank and the sphere.. no flow yet. It is apparently meant to come on for a couple of seconds to prime the system when the ignition is switched on.

Post by **mat_fenwick** » Sun May 06, 2012 6:49 pm

Is the relay clicking when cranking? If so the fault is with the fuel pump/pipework or wiring to it. If not clicking then the fault is with the relay, or what is triggering it.

JayW · Post by **JayW** » Sun May 06, 2012 10:26 pm

The 16V primes the pump briefly when the igniting is turned to the II position (before cranking). BUT, it is not uncommon not to hear it, some people do, some don't (it's one of those BX mysteries). You should however hear the relay click as Mat says.

Mine has blown the pump fuse on start-up after a long rest so also worth a check.

JayW · Post by **JayW** » Sun May 06, 2012 10:29 pm

As you don't have the manual, this: http://www.bxproject.co.uk/phpbb3/viewt ... =13&t=2477 may be of use to you.

toddao · Post by **toddao** » Mon May 07, 2012 10:35 am

Thanks Jay. I'll have another look this evening. I'm anticipating a bit of a palaver with this! I've checked the fuses already.

Kitch · Post by **Kitch** » Mon May 07, 2012 1:55 pm

On the 16v forum you can download a piece of software (can't remember the name right now) which is a fault-finding guide. You test pinouts on the ECU, perform certain procedures etc and the fault normally crops up (unless it was mine!)

toddao · Post by **toddao** » Mon May 07, 2012 8:11 pm

I grabbed a neighbour to sit in the car for a few minutes and activate the ignition while I listened: pump relay clicked when it was switched. Then when it was turned over I lay at the back and could hear the pump whirring away.

I disconnected the fuel line between pump and filter and turned it over again - fuel came out so I thought I'd better check the new filter. It tuned out that though it was a perfect fit in the rubber block that the flow was indicated going the other way on the casing! And it doesn't fit in the other way.

I put in the old filter and turned her over.. she fired into life then settled into a nice idle for a couple of minutes before gradually choking and stalling. And now won't start again.I'm hoping this is the old filter being clogged.. I've ordered the proper Bosch filter this time then we'll see if that was it..

I'm happy that it started at least ( dreading some ECU nightmare) and pumped up without pissing out any LHM after all the hydraulic work that I did over the last month.

Can anyone explain how these fuel filters work? It can be blown through both ways but why would liquid behave differently?

Thanks for help everyone.

Kitch · Post by **Kitch** » Mon May 07, 2012 10:27 pm

It shouldn't make a difference really. Sometimes they're arrowed because the connectors on each end differ in design or size, and sometimes the element inside is designed to retain crap on one side - the inference being if it caught it on the wrong side, it may block up quicker.

To be honest, something smells a bit fishy there

Gonna sound dumb, but is it on a hill? How much fuel has it got in it?