Have to check the ball on my T31.

 

hi, you said it its fine when the temp is up so glow plugs? or maybe early sighns of SCV problems.

 

Sounds like fuel running back due to the non return valves in the primer not holding the diesel

 

As above .Pretty sure there is a non return valve in the priming bulb so might be worth changing for new, or getting a good known working one to try.There are after market Non return valves you could maybe retro fit inboard of it . I have had this happen to me after changing the fuel filter, and the morning of the day after It stalled on me after initial start .I primed the bulb again till hard, but has been fine since.

 

Thanks all,

Yes, I was wondering about the primer bulb and I did buy another one (albeit a cheap no-name one on eBay), however, the problem persists. I'm starting to wonder if I've got a duff fuel filter? I might get another one and swap it again, just in case it's that.

I did also wonder about the dreaded suction control valves...!

Could I trouble you all to examine your primer bulbs (I won't say balls again!) when you come out to the car after it has been standing overnight and let me know whether they're hard or not, please? The only thing that is making me dubious about it all, is that once the engine has been run up to temperature, I can leave the car for 3 or 4 hours and it will start OK, even though the temperature gauge will say it's cold (albeit that the engine will still be slightly warm). That strikes me as a long time for the fuel to drain back!

 

I just checked the bulb on my T31 after standing all night & it was slightly soft. I have had no trouble starting.

 

and mine is soft on a cold start but can be pumped hard doesnt stay that way for long but mine is old :smile: but on a serious note could it be an air trap? Avocet if you have smone to help the thing to do is slaken of the feed pipes fittings where they meet the injectors one at a time or all and then pump the primer as it eases of you shopuld see the diesel leaking out if its to firm then get your helper to give the engine a crank and again if you see diesel.

 

Thanks all. Well, I fitted a new fuel filter yesterday and...

...it's no different. :sad:

I shall keep you all posted!

Just wondering if anyone who has done the dreaded suction control valve job could give me a rough idea how long it takes, please?

 

Also borrowed a generic fault code reader and there are no codes stored.

 

Just an update. The local Nissan dealer has had it for the last couple of days and they're flummoxed too! He was wondering about a stretched timing chain, but I'm dubious about that (having already replaced it about 15,000 miles ago, and it isn't rattling...

He said the Suction Control Valves were fine. Is it possible to check these?

 

Thanks all. Well, I fitted a new fuel filter yesterday and...

...it's no different. :sad:

I shall keep you all posted!

Just wondering if anyone who has done the dreaded suction control valve job could give me a rough idea how long it takes, please?

If you can be botherd or have the time its possible i have been led to bieleve you could take them out and then replace them upside down thus the flow pressure is now pushing on the outher side this is only a temp fix. i got new and did mine in around 5 hours i took my time and expect it could be done faster, i followed the forums how to it was easy and was allmost fun

 

I know you and i doubt it, but search for a 2 channel Pico scope and check the cam and crank signal

 

I know you and i doubt it, but search for a 2 channel Pico scope and check the cam and crank signal

Thanks, I think that's where I should look next. However, I would have thought that if the signal from the cam sensor was either breaking down or not as the ECU expected to see it, there would be a fault code? I'm also surprised that this only happens when the engine is absolutely cold. If I hold it at 1500 revs for even 1 minute (30 seconds is often enough) the problem goes away. I can't see how the tiny increase in temperature should make the problem go away, if it is a misalignment (or some sort of vibration) of the cam sensor / sprocket?

Anyway, pico scopes look expensive here in the UK. I'm a bit of an electronics numpty, but was wondering about something like this:

https://www.ebay.co.uk/itm/New-Assemble ... rk:35f:0

or this:

https://www.ebay.co.uk/itm/Hantek-6022B ... rk:20f:0

or even this:

https://www.ebay.co.uk/itm/Fully-Welded ... :rk:3f:0

?

 

I would have thought a fault code would have been store if this was a sensor or chain issue. Any fault with erratic fueling issues is likely to involve SCV valves. I noted when I changed my timing chain, that with the engine mount removed and the engine jackeed up, there was more clearance at the back of the engine. I need to change mine soon, and I think that's what I will try. I have seen somewhere that the job is about as difficult as changing the fuel filter, so maybe not as daunting as it may seem.

 

I would search for garage who has a Pico.
It has to be 2 channel scope to compare the signals.
What i heard that the pico has one the best softwares.

 

Ok thanks. I was tinkering with it again this evening, and have made an important discovery! The non return valve in the new priming bulb that I fitted DOESN'T WORK! I can blow through it both ways. I've put the old bulb back on (which I couldn't find anything wrong with when I took it off, and I definitely can't blow through the non-return valve in it the wrong way), so I'm eagerly waiting for the morning to see if that has cured it!

 

Correct me if I'm wrong, but I believe the priming bulb only serves to fill the empty filter after replacement, and should not affect normal running.

 

It acts as an one way valve too, not let the fuel flow back in the fuel tank.
It may be have some micro cracks, air is thinner than fuel.

 

Alas, it was no different this morning. Problem still there! Back to the drawing board....

 

More updates.

Searching around the internet in general, I came across this:

https://www.picoauto.com/support/topic14611-10.html

which I think it pretty much what Ah2 was talking about?

I went out to the car, cold, and started it. As usual, it stalled after a few seconds. I did this three times and each time, it stalled after a few seconds. I then unplugged the cam sensor and started it. I had to crank it over for a bit longer, but once it fired, it idled with no problem at all! I then plugged the sensor back in and it stalled. Unplugged it and it idled. This was very repeatable, so I am now in no doubt that the problem is related to it.

I'm guessing that there is nothing wrong with the sensor itself (or there would have been a fault code), but that the signal from it and the crank sensor are in some way out-of-phase? It's almost as if the ECU sees that there's a mismatch in timing between the two signals and then simply gives up!

In the link, you can see that various people are suggesting a "stretched" timing chain. As most on here will know, I replaced my upper chain only 15,000 miles ago, so I'd be surprised if it WAS that, but what else could it be?

Clearly, whatever mismatch it is, is SO small, that the TINY bit of heat you get from running it under no load for a minute, is sufficient to put things back in-step. That being the case, I'm toying with the idea of slotting the holes for the cam sensor to allow me to move it a tiny bit...

I'll let you know how it goes....

 

I note with interest the last post in the thread you linked to. I doubt the engine would run very well, if at all, if the valve timing was out. I have read somewhere that Almera and X Trail Vacuum Pump camshaft gears are different, and given your issues with this pump chain, maybe you have the wrong gear, or there is some damage causing sensor issues.

 

should it look like this notice the the 4 rased points and one with a ramp tdc perhaps? mine has that if the one thats in fitted is not the same and perhaps a spoke design like in the kits on ebay.

 

Yes, Avocet, I was talkt about that topic. My car was also for a benchmark, the faulty car had the timing 2ms off.

Maybe the aftermarket cains for nissan are rubbish, Maybe for Eastern europe, Japanparts uses a better supplier.

Des Marples uses BG Automotive kits. I do no know is the upper chain avaiable separetly from BG, With OEM is no problem to order the parts separetly.

 

Just wondering if the Dual Mass Flywheel is starting to go as this will effect the timing for the crank sensor.Take the crank sensor out,is it covered in lots of iron filings ?.Does the engine vibrate more than usual when running.Worth a look at anyway.

 

if it goes hard youve built up the pressure and the non return valve is fine start engine fuel spent presure drops to normal and so now soft....did you bleed it via the tap for air etc.