rpenyan

New Member
First I would like to ask a question:
If the common rail sensor is disconnected + pressure regulator seems to at least work somewhat, shouldn't the injectors fire?

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Now to my problems that would explain the question:
I use the car very rarely due to lack of parking spaces, increased insurance costs in my country, fuel prices and so on. Last year for example I might have traveled less than 1 month, so it mostly just stays parked on a slight slope (now nose down, formerly backend down), starting it very rarely. Three years ago I couldn't start it and called some mobile service that checked a bunch of things, among them they took out the low fuel pump, the crankshaft sensor, checked the fuses and I can't remember what else. They decided the LP pump was the problem and eventually unclogged it (they still spent nearly the whole day to prime it cause engine didn't start). When I took the car out it wouldn't rev over 2000, searched the forums and realized they must have put the crankshaft sensor back in the wrong position. Called another "expert" told him it's the crankshaft sensor and that I want to put it on position, gave him indications. He was insisting it's not, and that he uses the tester.. I let him use the stupid tester, listened to all his bs and then told him to freaking put the crankshaft sensor or leave. He put back the sensor, car back running normally. End of story.

Until the next year, when car didn't start. Couldn't hear the LP pump, gave it a few bumps and eventually did start, but I decided to replace it with the cheapest available. Made a lot of noise and not consistent. Sometime would the pitch of the buzz was higher. Nonetheless car worked until this year. Battery dead in the winter, took it home and recharged it. The pump didn't start. I figured it's clogged again. Gave it some bumps still didn't start. Called another mobile service (I'm not to keen to work there myself since as I mentioned before, the parking space is on a small slope) that changed the LP yet again and charged me a lot. After he took it out, I put it on the battery and eventually started after more shocks (well, bad luck) I drove the car a few days then after few months I needed it again. It wouldn't start, while the LP made its usual noise. I used the multimeter to check the battery and it was 12.1 V. I took it again up to my apartment and recharged it till 14.something V, but when I put it back on, while fastening the negative wire nut, the wire did slide in an awkward position and took it out put it again, forgetting about the tailgate window reset. The window did slide only halfway. I said to myself that, I'll deal with it later, first thing first to start the engine. It didn't start on the first try. I had to let the LP end its cycle about 3 times until it did start. And when the engine started I let it idle, it would fluctuate and grumble like it would not get enough fuel and want to stop. I would rev for a min or two until it would stop doing that. (BTW, tried to reset the tailgate again after buying new car battery by unplugging the battery, it wouldn't go down fully and when pushing either the dashboard button or using the key on the back door it would just rise a bit, stop and then make 4 "clank" noises in short succession. I keep it closed and when I changed the battery last time I had someone push the button while I raised it with my palms)
The starting issues continued as at some point I had to let the LP pump run about 10 times. Engine started eventually, still grumbling like it wanted to die at idle. Searching the forums I thought to change the gaskets on the Pressure regulator and for that I had to order them from UK. There were some sellers from Latvia, too, but while they're closer to me, the estimated arrival time was like a week longer than the UK one (lol).
The gaskets did arrive and I tried to take out the intake manifold, but the lower 5 nuts wouldn't budge at all, but I still managed to squeeze my hand and take out the HP regulator connector and WD40d it). I bought a fuel filter and took the car in a service (the same one that changed the LP pump prior), told him the symptoms and that I want the regulator gaskets changed. After 2 days I took the car back, started alright, but at a stop, on idle again started to grumble a little. Next day it didn't start at all and couldn't start it till now.

The LP makes its usual noise, the intake pipe on the HP pump feels fuel coming in. Took the engine cover off and used the WD40 again on the common rail sensor connector, the injector connectors (saw some diesel in the left injector slot, looks like the service dude unscrewed the pipe to see if there's fuel coming from the rail). Again I tried to take out the intake manifold to see if the service really changed the gaskets on the regulator. I couldn't, do it, the same 5 nuts are stuck. It seems the scumbag charged me for it and didn't change the gaskets. I sprayed a lot of WD40 on those nuts and will try to unscrew them again tomorrow, yet I'm starting to doubt the regulator is the cause. Here's why:
When I put the contact on and feel the small return fuel hose coming out of the HP pump, it kinda feels like fuel passes so when I have someone turn the key it doesn't feel like fuel passes on the same return hose. So when I take out the common rail connector and the maf sensor connector shouldn't the ECU give green light to the injectors even if the pressure on the rail wasn't best ever?
Cause the regulator seems to work at least somewhat (if it would feel like fuel passes on the return hose when trying to start the engine, then for sure the regulator would be the problem, but i didn't feel it)...
Nonetheless, I'll still try to take that dumb manifold in the morning cause I'm running out of (stolen) ideas. What else can it possibly be? The ECU itself? I mean I can't think of anything else...
 
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TD4 ? A common rail engine, no enought fuel presure, no start.

Check any fuel leak, or cracked fuel hoses, air can go in.

Injectors can be an issue, test the return flow.
HP pump can leak from one of it’s cover.

Also fuel rail sensor should have the updated loom. No fuel presure reading, no start.

First you should put a descent LP pump, cheap ones aren’t reliable. And test the injectors return flow.
 
I finally managed to take out the manifold (this took so much effort... glad I finally managed), still pretty cramped for the regulator. There's those two annoying hoses (cooling or something) and the electromotor. I gave a lot of wd40 on the 2 regulator bolts, hopefully tomorrow I'll take it out. After that i'll remove the rail sensor too...

As for HP, now that I had a better look at it and could manage to fit hand mostly everywhere, it doesn't show any leaks. Likewise there aren't leaks on the hoses (at least nowhere under the hood as far as I could see), no sign of leakage under the car or on the shield.
 
I use the car very rarely due to lack of parking spaces, increased insurance costs in my country, fuel prices and so on. Last year for example I might have traveled less than 1 month
suggestion .. get some ,
smear it on all sensor contacts .. i.e. plug/socket pins.
and ..
this has a biocide in it .. to prevent diesel bug ..
and a water dispersant ..
.
 
Hi

You can use a fault reader, to get any fault code ( first erase all codes ).
Testing the fuel leak back on the injectors can spot a clogged injector.
 
I finally managed to take out the manifold (this took so much effort... glad I finally managed), still pretty cramped for the regulator. There's those two annoying hoses (cooling or something) and the electromotor. I gave a lot of wd40 on the 2 regulator bolts, hopefully tomorrow I'll take it out. After that i'll remove the rail sensor too...

As for HP, now that I had a better look at it and could manage to fit hand mostly everywhere, it doesn't show any leaks. Likewise there aren't leaks on the hoses (at least nowhere under the hood as far as I could see), no sign of leakage under the car or on the shield.
Did you fix it?
 
No. Not really.
Gone to some mechanic, changed the injection pump (along with the regulator). After a few days it would start like tractors, very slow, having to keep acceleration pedal and key on starting position for a long time. Few days ago same thing and the next day it wouldn't start at all.

Used some antibacterial diesel aditive (JLM diesel, cause the one recomended by @hd3 I couldn't find here), but still no luck.
Took the manifold out, took the fuel rail out too and cleaned it with high pressure water and indeed got some muck coming out of it. Put it back on after drying it for a day, mounted the pressure sensor back, but I left a pipe open to see if fuel comes. It didn't (though both the LP and HP make noise).
Next I might have messed something up even more as I took out the rail pressure sensor jack with the keys in the ignition and after I put it back on the yellow engine light came on and stays on...

I don't know. Tomorrow I think I'm gonna take out the feed line to the HP (injection pump), turn the contact on an see what comes out. Then if the diesel is decently clean, gonna take the regulator out again and clean it.
(when I took the old one out myself it was pretty clean the gaskets where ok, but I changed them anyway at the service afterwards. Next day after service changed them it didn't start again and after the service changed the injection pump with the regulator altogether, the rod on the old one was somewhat dirty and a bit sticky).

I'm thinking of also taking all the diesel out through that feed line to the HP while having the contact on and have the LP pump it all out through there... (there's about 30L as I have added some more since).

Also that rod on the regulator moves up and down, no? Would be safe if I test it directly on the battery?
 
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No. Not really.
Gone to some mechanic, changed the injection pump (along with the regulator). After a few days it would start like tractors, very slow, having to keep acceleration pedal and key on starting position for a long time. Few days ago same thing and the next day it wouldn't start at all.

Used some antibacterial diesel aditive (JLM diesel, cause the one recomended by @hd3 I couldn't find here), but still no luck.
Took the manifold out, took the fuel rail out too and cleaned it with high pressure water and indeed got some muck coming out of it. Put it back on after drying it for a day, mounted the pressure sensor back, but I left a pipe open to see if fuel comes. It didn't (though both the LP and HP make noise).
Next I might have messed something up even more as I took out the rail pressure sensor jack with the keys in the ignition and after I put it back on the yellow engine light came on and stays on...

I don't know. Tomorrow I think I'm gonna take out the feed line to the HP (injection pump), turn the contact on an see what comes out. Then if the diesel is decently clean, gonna take the regulator out again and clean it.
(when I took the old one out myself it was pretty clean the gaskets where ok, but I changed them anyway at the service afterwards. Next day after service changed them it didn't start again and after the service changed the injection pump with the regulator altogether, the rod on the old one was somewhat dirty and a bit sticky).

I'm thinking of also taking all the diesel out through that feed line to the HP while having the contact on and have the LP pump it all out through there... (there's about 30L as I have added some more since).

Also that rod on the regulator moves up and down, no? Would be safe if I test it directly on the battery?
Hi total curve ball and probably not the exact cause but I've had a very similar and very annoying problem with my own td4 the past 2 years. It was being misdiagnosed by diesel specialists as fuel rail problems but after changing my lp (3 times) and hp pump I mistakenly came across the fuel/water separator...
My lp pump was constantly clacking, which I was mistaking for failure, but you've got to remember the LP pump also primes the fuel... long story short my car was old enough that the O-rings in the separator were sucking enough air in that my fuel was constantly priming... not actually sending fuel through to the HP.

It worked when the HP kicked in because there was enough of a vacuum to pull the fuel through itself. Having read your thread, I would advise as a minimum to check your old rubber seals. I bypassed the separator myself and put an inline filter in instead for monitoring purposes. It starts up first time now.
 

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