Citroen C4GP 1.6 HDi: Crank > rough start, choppy revs > white smoke from engine bay > cuts out

[uzigon]

I figured I could start a new topic as this is looking to be a separate issue now.

I recently replaced the clutch on my EGS, as somewhat detailed here: viewtopic.php?t=85589

Now I have put everything back together and I can no get the motor to run. I am recollecting having some funny behaviour along these lines before I did the clutch replacement, and I am wonder if these were symptoms that I had mistaken to be the clutch (which definitely needed to be changed). I was getting a loss of throttle response, and then the engine would cut-out. I was able to restart it before, but there was a erratic loss of power in the low revs. This only happened a couple of times before I parked the vehicle for the clutch replacement.

I have attempted to start the motor several times now, and I have tried to get the revs up to 1500 rpm but I don't get the power I am requesting, the engine struggles to reach idle and eventually cuts out and the battery needs to be removed for recharging.

Other work I had done while it was parked up for servicing.

-Replaced coked up EGR with a cheap knock-off from amazon
-Replaced butterfly doser/throttle body with an OEM part from eBay
-Fuel system was disconnected and fuel filter removed for 5 weeks
-Removal of DPF and cleaning of temperature sensor
-Gearbox removed and cleaned and 'rebuilt' to an extent

Suspects:

EGR:

I am inclined to suspect the EGR at the moment, but I feel like it would be unlikely for it to completely stop the motor from running.

I performed as many actuator tests as I could find using Diagbox and everything is sounding out, although the electronic whir from the EGR doesn't sound great, it does click (I am in process of removing this for a visual check of actuator moving.

HEAD GASKET:

I also noticed a massive loss of coolant, there are no leaks to be found. Some coolant got out when I was moving the rad in order to access DPF, but the level is below the minimum mark now that it is lower back to ground (on a slight slope). What concerned me was the amount of white smoke coming from the engine bay on each attempt to get the motor idling. It is a thin but heavy white smoke with maybe a slightly sweet smell, but mostly smelling like exhaust. The coolant in the reservoir is murky and dark brown, with a grimey smell to it. No signs of 'milky oil' under the cap

FUEL PUMP/FUEL RAIL SENSOR:

Without being able to get it to idling I haven't been able to collect any good data about the fueling, the cam and crank sensors synchronise, the fuel pressure while in ignition seems ok.

I was definitely having problems with fuel aeration, but I feel like the system is still priming properly (I can feel fuel moving through the lines and the primer bulb gets very firm but not ever impossible to squeeze).

I'm not sure what kind of tests I can do on the Fuel Rail Pressure sensor in order to ensure it is working properly, any tips? I have only performed visually checks and it seems ok.

IMMOBILSER:

I doubt this one as I was already able to start the motor, unless the immobiliser has a delay that cuts the fuel. My key seems alright, but I don't get a beeping when I leave it in the ignition, plus why the white smoke?



Any suggestions? I am nearly two months in and thousands of euros already on this one, it would be a real shame if I couldn't get it running again.

Cheers!
CB

[RichardW]

If the EGR is stuck wide open it can recirculate enough exhaust gas to cause running issues. A cheap one from Ebay / Amazon is never likely to be any good.... Where is the smoke coming from?

[uzigon]

Smoke appears to be coming from the bottom of the DPF area, likely from under the shield. It seems like something is blocked, like as if the EGR doser was closed and not letting air in - maybe the EGR is open and creating a vacuum.

Would it be wise to remove the EGR and blank it, the try starting the engine without it?

[uzigon]

New part that I had just installed already coated in sludge from the few attempts at starting. I am going to start dismantling the EGR system to see if the cooler is damaged.

[uzigon]

I've also noticed that while I have been using Diagbox, what I suspect to be the fuel injection pump continues to make a buzzy whir, unlike I have noticed before. I thought it only would run for a moment upon ignition on and after stopping the vehicle. While I was connected to Diagbox it ran continuously which I thought might be odd.

[uzigon]

Does anyone know what this port connects to? Does it connect with the EGR somehow? It is a fifth port on the exhaust manifold, I had oil coming out of the bolt holes.

Dismantled turbo today to find completely dry oil return line. The banjo bolt at the top looks normal, although there was quite a bit of play in the feed pipe even when tightened up. I assumed this was normal. Will be dismantling turbo for a inspection/rebuild.

[uzigon]

To try to answer my own question, I think that port might connect to the EGR port on the backside of the motor. Why I have so much oil in those threads is still a mystery.

Upon pulling apart the turbo, I see why my oil drain pipe is dry. Bear in mind this system had been checked by myself and two mechanics and the trace amounts of oil in the intake system were being blamed on the PCV (which needed replacing along with the O ring on the turbo pipe). Unfortunately my oil dip stick broke last November and I have been holding in good faith that the oil has been good since having the oil changed out in December. Now I am wondering what the inside of the sump looks like, I found chunks of gunk mixed with the oil inside the turbo housing. The screens had been removed from the banjo bolts but it looks like the seals gone on the cartridge.

This car has become alarmingly expensive to maintain, quickly outweighing any fuel or tax savings.