TD4 turns over but will not run after work done

Hi folks...I'm having a bad hair day
After replacing the water pump and a few other jobs, put everything back and the engine turns over but will not run apart from trying the instant the glow plug lamp goes out for a second or so.
It's a 2002, TD4, manual with Synergy 2A & Pierburg MAF. The car has had no problems starting in the past. As a "Newbie" of sorts on diesels, I am stumped
This is the work done:
Removed Camshaft cover and Injectors to check condition of Camshafts & chain-call it preventative maintenance inspection (All is good).
Replaced frayed vac. hose from turbo valve to plastic vac. tank.
Replaced water pump/stat assembly.
Oil & filter change, air filter change, main serpentine belt change.
Upon reassembly, new gaskets fitted to Camshaft cover & inlet manifold.
Injector seals replaced and Injectors refitted to original positions.

During dismantling, the fuel rail was disconnected from injectors. When the engine would not run I cracked the fuel feeds to each injector in case there was air in the pipes..there was and I tightened the nuts when fuel was flowing freely from all injectors-I understand the TD4 is supposed to be self bleeding.
The electrical connectors I recall unplugging were : MAF, Inlet manifold, camshaft sensor and injectors....all have been treble checked and the synergy MAF connector will only go one way.
The battery has gone flat through trying so I have put it on charge overnight.
Apologies for the long thread but I wanted to give as much information as possible.
I look forward to getting any input, especially from TD4 gurus.
Cheers guys

Morning bud i had a similar problem check the low pressure pump in the tank is working ok all the best Ryan

if you are getting fuel to the injectors then the pump should be fine ,as you have not done any major jobs like removing any of the pumps ect. all should be fine just go over electric connections again making sure all plugs are fully home and if you battery was flat make sure it is full charged up ,it is surprising what a difference it can make .

Thanks for the input guys-appreciated
Just gone out again to the car, the battery was fully charged overnight.
It spun over like an express train, but it's still not starting. As my first post, it tries to "Catch" a split second after the glow plug light has gone out but after that initial kick just spins over without any signs of firing.
Regarding the fuel pump, with the ignition onbut not cranking, The low pressure pump (Behind the rear wheelarch) can be heard running then stops after a while. Yesterday I cracked the injector connections and bubble free fuel flowed freely. When I cranked the engine fuel gushed out at a higher rate.
Looks like yet another top cover stripdown and connector check
Failing that, will remove the inlet manifold and Cam cover just to double check that the gaskets are sitting correctly....I am pretty sure though that they are.

It does point towards a leaking back injector, or rail not pressurising, have seen it once before , engine running fine, injectors removed put back in and it caused the issue.

I know a lot will say don't do it, but as a easy test, use a squirt of easy start, if it fires and runs fine till its switched off then problem could be the injector.

When I changed my thermostat a couple of weeks ago I removed all of the bits you did.

Upon reassembly I noticed that there were two plugs that could connect to the cam sensor. One came from a lead attached through the main fuse box, the other was part of the loom that sits around the engine. For me, it's the former that is the correct plug. You might have the same arrangement.

Also - make sure you have pressed the 'out of fuel' button that sits below the crossed out petrol pump on the RH side of the bulkhead.

sijwhite said:

When I changed my thermostat a couple of weeks ago I removed all of the bits you did.

Upon reassembly I noticed that there were two plugs that could connect to the cam sensor. One came from a lead attached through the main fuse box, the other was part of the loom that sits around the engine. For me, it's the former that is the correct plug. You might have the same arrangement.

Also - make sure you have pressed the 'out of fuel' button that sits below the crossed out petrol pump on the RH side of the bulkhead.

Click to expand...

:behindsofa:

Many thanks for that.....I will pop the front air duct off in the morning and have a further check of the connectors, especially the one you refer to. Regarding the "Out of fuel button", the sign is there-on the bulkhead foam insulation but I cannot seem to see the button referred to, only a lone relay just to the right of the sign. I have looked all around the area, especially by the large, downward pointing white arrow. Is it under one of the plastic covers which house the engine bay electronics and fuses ?

Irishrover said:

:behindsofa:

Many thanks for that.....I will pop the front air duct off in the morning and have a further check of the connectors, especially the one you refer to. Regarding the "Out of fuel button", the sign is there-on the bulkhead foam insulation but I cannot seem to see the button referred to, only a lone relay just to the right of the sign. I have looked all around the area, especially by the large, downward pointing white arrow. Is it under one of the plastic covers which house the engine bay electronics and fuses ?

Click to expand...

I pressed the top of the box that's under the arrow and it clicked - it has some sort of button on the top that's a bit like those tamper evident seals you get on a jam jar, if you know what I mean.

I'll take a photo if that helps.

the td4 is self priming so no need to crack the fuel lines,

you mention the maf, but not the map sensor, have you reconnected it ?
do you have any engine management lights on ?

sijwhite said:

I pressed the top of the box that's under the arrow and it clicked - it has some sort of button on the top that's a bit like those tamper evident seals you get on a jam jar, if you know what I mean.

I'll take a photo if that helps.

Click to expand...

:behindsofa:
All the times of looking under the bonnet during the last year + of ownership..and there's been many of them !!-I have never seen the switch. Yes, a photo would be of interest. The car is one of the early facelift versions. I have been told by the main stealers that according to the VIN the fuel filter is under the bonnet when in fact it's behind the rear wheelarch. If needs be, I will upload a photo of the area after your photo has been posted

john t said:

the td4 is self priming so no need to crack the fuel lines,
:behindsofa:
Yes, I know but when it wouldn't fire up I knew that the fuel rail had been hanging free after removing the injectors so had probably drained itself. The injectors were left on the bench for about 3 days awaiting new seals and studs so they may also have drained. I remember last year after changing the fuel filter that it took quite a while before the juice came through and it fired. When it wouldn't fire up this time, my thoughts were to help things along by cracking open the injector connectors, one at a time until there was a steady flow of fuel. I am aware that the system is supposed to be self bleeding.

you mention the maf, but not the map sensor, have you reconnected it ?
do you have any engine management lights on ?

Click to expand...

I am 99.9% certain that all connectors were refitted in the correct place. Where is the location of the MAP sensor ?

No- the EML lamp is acting normally, even when cranking

Thanks for your input guys

booboodag said:

It does point towards a leaking back injector, or rail not pressurising, have seen it once before , engine running fine, injectors removed put back in and it caused the issue.

I know a lot will say don't do it, but as a easy test, use a squirt of easy start, if it fires and runs fine till its switched off then problem could be the injector.

Click to expand...

:behindsofa:

Thanks for your reply.
As a relevant "Newbie" to diesels, having always had petrol cars before, I am finding this a baptism of fire....but not where it should be-in the cylinders !!!
Thanks for the tip but I have a question-As it is unlikely that all 4 injectors would fail I would expect that the working ones would still cause the engine to fire up albeit running lumpy-is my logic correct ?
There seems to be a good steady flow of fuel from the injector connections when cracked open with the ignition switched on and the flow is considerably greater when the engine is cranked and the high pressure pump is activated. Bit like a stream and a torrent !

Due to it being a common rail system it not like a petrol where if it was a spark plug failure it would run on 3 cylinders.

If 1 injector fails it will not pressurise the common rail and will not start, on cranking if memory serves you need to obtain around 2000 psi on cranking once it fires it then runs at 28000 psi.

Thanks for the clarification Booboodag-appreciated.
The injectors were removed as per RAVE, numbered per their position in the engine and replaced in their original locations. They were not subjected to any damage or dropped etc. whilst they were out. I cleaned the rust which had accumulated around the top end, under the coil, where the clamp sits with a brass wire brush-The fuel inlet was covered with masking tape to prevent any dirt etc. getting in. A new "O" ring was fitted to the body and the copper washer at the bottom of the injector was fitted.
So....if an injector has failed, how can I identify which one it is and how can the problem be resolved ? Is it a case of sending all 4 injectors away for repair or service ?
Is this a common problem ?


As an additional comment to another post regarding the MAP (Not MAF) sensor...If this is the one located under the inlet manifold on the l.h. side looking into the engine from the front-Yes it is connected. It is a square(ish) plug with a wire spring clip.

I bet you wish you had not started and the button you are on about is square and black right there on top of the insulation on the right as you look at it

I have just been Googling "Injector checks" and came accross this site
Diesel Injector Testing FREE Bosch Delphi Test Solenoid Spray Pattern

They are based in Birmingham. Should I send them off for checking and which check should I go for...The minor check at £10 each or the full check at £30 each.

I was reading about a diy check for leak off rates using 4 identical bottles connected to the leak off pipes but I would rather send them off to somewhere with the right equipment and who know what they are doing and looking at plus give a report of their test results.
Just can't get my head around why this happened after pulling the injectors out and replacing them Surely, this must happen often and is not just an isolated incident ?

teddywood1 said:

I bet you wish you had not started and the button you are on about is square and black right there on top of the insulation on the right as you look at it

Click to expand...

:violin:
Hi TW...Yes it's there !!! Tucked down low and in a corner, has a red top-I must have a trip to Specsavers !!:hysterically_laughi

Yes, I have wondered why I started the job
It's my first encounter with a diesel and boy, am I paying for it. With all the complexities of the P38, V8 and it's electronics it was a walk in the park compared to this hassle. Stripped the V8 down to it's bare bones, rebuilt it and always fired up first turn of the key. Can't get over this "If one injector goes down,that's the engine start scuppered". It's years of working on petrol cars that makes me automatically think of them when trying to trouble shoot. After Googling Injector problems etc. I can see where other posters to this topic are coming from and really appreciate the input. In order to rule out the injectors I am now seriously thinking of pulling them out and sending them off for testing/servicing. Luckily we have Er Indoors Vectra which we hardly use so we are not stuck. Only downside is, living in a very rural location it's not easy just popping down the road to a reputable repair specialist-everything has to be done by post etc.
When we lived in the Midlands, it was easy and at worst, if I couldn't get a lift there was always the bus !!

I'd be surprised if after the work you've done then suddenly you're injectors have failed and prevent starting.

You really need to get the fault codes read and some basic diagnostics carried out on T4 etc. to pinpoint the root cause of the issue.

Have you checked the crank sensor wiring and made sure the pins have been pushed backwards and are not making the connection anymore?

td4van said:

I'd be surprised if after the work you've done then suddenly you're injectors have failed and prevent starting.

You really need to get the fault codes read and some basic diagnostics carried out on T4 etc. to pinpoint the root cause of the issue.

Have you checked the crank sensor wiring and made sure the pins have been pushed backwards and are not making the connection anymore?

Click to expand...

I didn't remove the CPS. I have a Rovacomlite and am seriously thinking of getting the engine diagnostic module after this pantomime !!

One reason I don't like doing do much engine work/messing at the same time as it's harder afterwards to back track to where you buggered up !!

Sorry can't help any more, the wifes got a 2001 TD4 with has had the "mill light" on for the last 3 years , 320 000 Km's and it's never missed a beat ! Touch wood !

if you removed the air box (plenum chamber) you would have disconnected the map sensor (mass air pressure), its located at the lhs as your looking at the engine