Engine not starting.

[Heath Robertson]

Hi all. Recent engine swap from Rx into stx and been running for a few weeks..

Recently had the car in for a road worthy to get registered.. needed a ball joint, tap rear wheel bearings and changed scv as it occasionally stalled.
Did all the work and turned car around and swapped out the SVC ready for reinspection... And it's not started since. I changed out the SVC back to original and still no go. So since then I've changed orings and gasket on SVC, and checked power at injector. Nothing with rest lamp.

Today I checked ECM power from the idpr and power in fuse okay and relay power out with ignition on.

So not sure what's next. Or what else could be the issue? Engine turns over. Glow plugs have power.. pressure to rail...

Any ideas or suggestions?

 

[Heath Robertson]

I've checked the opv for leaking. Nothing.

Primer bulb goes hard and I'm guessing as I have pressure on rail from odb2 reader probably okay.

What stops injector power?

Any ideas??

 

[bshrngr]

I've checked the opv for leaking. Nothing.

Primer bulb goes hard and I'm guessing as I have pressure on rail from odb2 reader probably okay.

What stops injector power?

Any ideas?? View attachment 38546

1000 kpa isn't enough rail pressure to start ... disconnect the SCV plug and see if it starts ... Don't drive it like that though ... It might need a SCV re-learn performed on the ECM ...

 

[Heath Robertson]

1000 kpa isn't enough rail pressure to start ... disconnect the SCV plug and see if it starts ... Don't drive it like that though ... It might need a SCV re-learn performed on the ECM ...

I've done a few ECM relearn pedal dance tries. And had the engine light show 0000 for no codes. Left it for a bit and then final 10 second depress to clear learner values.

Still no joy.

Is it safe.to run the engine/pump with scv disconnected?

 

[bshrngr]

Yes it will rattle a bit on start up because it will have max fuel press and push over the rail relief but will settle down and run after a few seconds ... The pedal dance does that but sometimes it doesn't re-learn even though it says 0000 ... speaking from hard won experience !!!
Disconnecting the SCV is just a test to aid the diagnosis not a fix ...

 

[Heath Robertson]

Yes it will rattle a bit on start up because it will have max fuel press and push over the rail relief but will settle down and run after a few seconds ... The pedal dance does that but sometimes it doesn't re-learn even though it says 0000 ... speaking from hard won experience !!!
Disconnecting the SCV is just a test to aid the diagnosis not a fix ...

Thanks for that explanation.

I disconnected scv and then tried to start. No change in behaviour, and to confirm I also ran the odb2 scanner and it showed very similar results. So, can same be done with the rail pressure sensor? Or that be broken so car thinks there is not enough pressure..

 

[bshrngr]

Well that test tells you you possibly have no rail pressure ... to confirm this leave the SCV disconnected and remove the hose from the rail relief at the rear of the fuel rail ... crank the engine and see if there is any fuel coming past ... if it's a trickle the relief is leaking and needs replacing ... if it pisses out you have rail pressure and we're looking in the wrong area ... another quick test whilst your doing this is to make sure the engine will run on "aerostart or start ya bastard" just to confirm it's not some other major mechanical failure that's stopping the proceedings ... it's very rare that the fuel pressure sensor is the problem but it's possible ... normally the engine will have a fuel sensor related fault code if it is ... disconnect it and try to start it while the SCV is disconnected as well ... the engine should still run and the scan tool should display 50mpa rail pressure with it disconnected ... as well as 3 fuel system related fault codes ...

 

[Heath Robertson]

Well that test tells you you possibly have no rail pressure ... to confirm this leave the SCV disconnected and remove the hose from the rail relief at the rear of the fuel rail ... crank the engine and see if there is any fuel coming past ... if it's a trickle the relief is leaking and needs replacing ... if it pisses out you have rail pressure and we're looking in the wrong area ... another quick test whilst your doing this is to make sure the engine will run on "aerostart or start ya bastard" just to confirm it's not some other major mechanical failure that's stopping the proceedings ... it's very rare that the fuel pressure sensor is the problem but it's possible ... normally the engine will have a fuel sensor related fault code if it is ... disconnect it and try to start it while the SCV is disconnected as well ... the engine should still run and the scan tool should display 50mpa rail pressure with it disconnected ... as well as 3 fuel system related fault codes ...

I'll try the start ya bastard and pressure sensor test this evening. I did disconnect the banjo/ line from opv. Nothing leaked from valve but in cranking motor there was fuel out the opv return line. Should that be expected? Same seen when using priming bulb too, once it was hard then noticed diesel from opv return line.

 

[bshrngr]

Yes that's normal as it is plumbed to the return circuit ... you can just cap it off with a plastic plug ... if you have rail pressure pushing over the relief you will have fuel spraying everywhere so be careful and don't get too carried away with the aerostart ...

 

[Heath Robertson]

So went through the various tests. With the scv disconnected I removed the fuel rail pressure sensor too. The reading was high on my odb2 app but still no starting.

The fuel rail pressure remained low.

Then I disconnected cool side intercooler pipe and sprayed engine starter in. The engine fired ran for a moment.

Final test was to disconnect the cam sensor to ensure we're not suffering from stretched cam chain. So cam sensor error and no starting.

So at this stage engine seems okay, but no fuel so electrics or diesel.. not liking where this is heading...

 

[bshrngr]

Firstly, congratulations on your good efforts so far ... this is the first time I've tried this sort of remote diagnosis ... usually it ends up like a game of "Chinese whispers" but your doing a good job ... so lets press on ...
It would seem you don't have rail pressure and therefore no injector pulse as the ECM looks for around 28mpa before it attempts a start ... so I would be supplying fuel directly to the fuel pump to eliminate the rest of the fuel system as a cause ... take the line off the pump inlet and feed it directly in there from a jerry can with gravity feed ... cleanliness is important as there is no filter when doing this but the filter or fuel primer may well be the cause so it's a necessary step ... leave the SCV disconnected ... and the relief to if you've still got it off ... look for pressure on the OBD2 or fuel pushing over the relief ... if all this still leaves you without pressure then I'm afraid your looking at a stuck SCV, failed pump or possibly a stuck injector ...
To try to determine which I would undo the feed line to the rail and see if the pump is at least pumping something up to the rail ... it wont look like much as a CRD is all about pressure and there's not much flow involved ... if it's stuck an injector open that can be enough to dump the cranking rail pressure back to the tank ... if that's the cause often tow starting can get you through that phase then you can work on diagnosing which injector after it's running ... if nothing tow starting whilst watching pressure on the OBD2 will give a clue too ... if your good with a spray can you can master the art of running it on aerostart or WD40 (less volatile) instead of tow starting but it's tricky to do and they make horrible noises when you get it wrong ... not to mention the backfires caused by the glow plugs ... have a fire extinguisher handy if you try that method ...

 

[bshrngr]

As an after thought in regards the the Cam Sensor test ... I seem to recall that they will run without the cam sensor but not the crank sensor for some reason ... which is weird as I've no idea how it knows whether to fire No1 or 4 but some how it does ... it should be the other way around ... maybe they just try both till one works ... weird science ???
So don't rule out some sort of crank sensor fault ... but if you've got a RPM signal I wouldn't think it's the problem ... rail pressure would be my focus for now ...

 

[Heath Robertson]

As an after thought in regards the the Cam Sensor test ... I seem to recall that they will run without the cam sensor but not the crank sensor for some reason ... which is weird as I've no idea how it knows whether to fire No1 or 4 but some how it does ... it should be the other way around ... maybe they just try both till one works ... weird science ???
So don't rule out some sort of crank sensor fault ... but if you've got a RPM signal I wouldn't think it's the problem ... rail pressure would be my focus for now ...

Thanks for the detailed reply, and information.. it's very appreciated.

I've got my local mechanic heading over with his workshop odb2 scanner. Hoping that it will show details I'm not seeing on my phone app and generic Bluetooth scanner..


I'll have a think about how I could jerry rig a gravity feed for fuel to the pump. I've also got a second Spain filter and pump I could fit, and have a Thai filter mount, with the plunge pump..i got it.to fit to use the cheaper filter and preferred that primer.. but as I never had the return valve thingy so I never fitter it.. but could try one of those combinations as an alternative?

The Thai primer water trap has two wires and a different connector to the Spanish one with three wires.... So that was an added inconvenience to the swap. And I had too much else on getting the engine swap finished.

 

[Heath Robertson]

So updates... Had mechanic come over and we went through our various tests to get to this point.

He setup his scanner and had a look at the car. The scanner shows that I have pulse to the injectors..so that's good. And we checked scv again. Both connected and disconnected.

We then removed the injector return line and again turned the engine over. Nothing there!!

So cracked a injector line on the common rail and no seeping.. so no pressure.

So I think I'm now looking at the fuel pump. These is plenty of fuel..

I have since taken external line off pump that connects top and bottom pistons on pump and run air and fuel through pump. And blown in return to tank line with SVC out. And then reassembled..nothing

Anyone got further suggestions?

Can pump have some service done while installed on engine?

 

[Heath Robertson]

SO had the mechanics in with their scanner and they have checked to he fuses and relays and so far found .... Nothing....

All injectors bleed up to rail output connectors. Starts on engine start.. removed filter and tried to run on diesel pump/injector cleaner. Nothing new there. Used second primer I had to pump cleaner into engine pump and then turned over with engine start to get diesel cleaner into injector pump and rail. But cars still not running.

Almost outta ideas.