No engine start - U01400 fault

[bluezie]

Oh sorry I missed that bit on the thread

I missed that too, but going through the posts, there was a mention of the failed EGR at post 4, but not what was repaired, then a mention of a damaged engine at post 35, but not what was damaged, then at post 38, it turns out the engine was hydro locked! This is all very significant information, and very likely the root cause of all of this.
I think you need to post an exact timeline of everything mechanical that has been done to the engine.
In my view, if it ran before the hydro locking, it's extremely unlikely to be anything else that has coincidentally failed. The no. 1 suspect is camshaft timing, be it spun lobes, spun camshafts or basic belt and pump timing.

 

[gonze]

Thank you for the replies. Please see below my time line:

- I purchased the caravelle as a non runner. Had been diagnosed at a VW main dealer as failed EGR and bent con-rod then was sent direct to auction.

- I then stripped the engine down and replaced the EGR, con-rods, pistons, piston rings, head gasket, head bolts, inlet & outlet valves, timing belt, water pump, dual mass flywheel, clutch, cam belt & tensioner, aux belt & tensioner, main bearings, piston shells, cylinder three pressure sensor with glow plug. I sure I have missed a few bits from the purchase list .....

- I have now had the injectors tested and replaced them with 4no. refurbished injectors

Currently something is stopping the high pressure fuel pump from activating. I have fuel in the low pressure flow and returns but nothing out of the high pressure side. I have tried another complete fuel rail but it made no difference.

A couple of the valves where slightly bent but not drastically.

I had cylinders honed and installed over sized pistons. Whilst at the machine shop I had the crank checked and it was perfect.

Lastly, I have tried starting with the cam sensor unplugged which didn't make a difference

 

[n10n]

Currently something is stopping the high pressure fuel pump from activating. I have fuel in the low pressure flow and returns but nothing out of the high pressure side. I have tried another complete fuel rail but it made no difference.

Fuel metering valve is what controls how much fuel is let to the rail in order to build up the pressure. Since the HPFP spring was ok I guess next it would be in order to check if the metering valve is activated by the ECU. Please log the following advanced measuring values while cranking for a bit. Do tick the Group UDS requests checkbox and select by 7 from the dropdown before starting logging.



IDE00021 Engine RPM (U/min)
IDE00589 Fuel pressure (kPa)
IDE07821 Fuel metering valve: activation (%)
IDE05633 Valve for fuel metering: feedback value measured (mA)

 

[n10n]

Must assume that the air filter box is not in place as no indicated airflow during cranking.

Also the airflow mystery @mmi noticed in post 11 is still unaccounted for - if there really is no airflow the engine cannot run. I suppose engine should run with MAF sensor disconnected but would it start after a major engine overhaul without airflow information?

 

[bluezie]

Also the airflow mystery @mmi noticed in post 11 is still unaccounted for - if there really is no airflow the engine cannot run. I suppose engine should run with MAF sensor disconnected but would it start after a major engine overhaul without airflow information?

Yes it will start and run without any air flow information. It really doesn't need much information at all to start, most sensors are redundant. As soon as the engine is put under load, limp mode values of MAF data are substituted, and the engine will drive at significantly reduced power.

 

[gonze]

I will do VCDS log of the metering valve tomorrow. The air box sensors are connected but the charge cooler is removed to enable access to the injectors and fuel rail so I guess that’s why it’s showing no airflow.

Found a post about a faulty crank sensor being identified by the rev gauge not moving when the engine is cranked. Mine does not move at all, until I use easy start, but VCDS gives a value of circa 300rpm. Could the crank sensor be the issue?

I have read a number of posts where people have adjusted the timing due to being a tooth out etc. If my timing aligns with the timing kit can it still be out?

Thank you all for the help

 

[bluezie]

I have read a number of posts where people have adjusted the timing due to being a tooth out etc. If my timing aligns with the timing kit can it still be out?

Yes, as explained before, if the engine has hydro-locked, the camshafts can rotate on their sprockets, and the lobes can also rotate on the camshaft. This will put the cam timing, and cam sensor timing out, despite the belt timing being perfect.
If anyone is purposely putting the timing 1 tooth out, this not right, it's basically covering up something else that's out of time, which should be sorted not bodged. !
1 tooth out is a big deal on a diesel engine!

 

[gonze]

My van is still not starting

Had a mechanic and now an auto Electrican go over the engine and neither found the issue.

The only fault showing is the (U14000) U0140 LIN fault. I have replaced the LIN cable from beneath the battery to the alternator/BCM/Battery shunt but the fault remains. What else is there to check to try and resolve this fault?

Would the LIN fault stop it starting?

Any advise is appreciated!

I have replaced the crank sensor and the van is getting a crank speed and fuel rail pressure reading even with the sensors unplugged. Is that normal?

Auto Electrican’s findings:
- 205v to injectors. No signal & no active voltage
- 5V on MAF sensor
- 12v from fuel pump relay. 10.38v by-Pass from ECU
- no control (Pulse width) on ECU B block
- fuel rail pressure without sensor plugged in

He seemed to think the ECU was the fault and advised replacing but was not sure

 

[gonze]

As the crank sensor pick up is in the rear main seal have I messed up aligning the seal? Should the centre of the oil seal align with the blind hole on the crank end rather than 180' opposite?