[Avocet]

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....

 

[Colster]

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.

 

[pete-H]

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.

 

[Ahto42]

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.

 

[leafy]

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.

 

[pete-H]

Hard or soft?

I am, of course, referring to the priming bulbs on the T30 2.2 DCI diesels! I still can't get to the bottom of this problem on Mrs. Avocet's car. Go out in the morning, turn the ignition on, wait until the glow plug light goes out, crank it and it fires up, pretty much instantly...

...and then stalls a few seconds later.

It will re-start, without any trouble at all, but then stalls again a few seconds later. If I catch it and hold it at 1500 revs or so for about 30 seconds, it's fine, but idles roughly. After about a minute or two it is absolutely fine. No other poor running symptoms. Temperature DOES seem to be a factor, because on frosty mornings, it will have to be held at about 1500 revs for a bit longer before it will idle.

Now the only time it has ever done something similar, it is just after I have changed the fuel filter. However, after a couple of re-starts, it's fine. At present, when I go out to the car in the morning, the fuel priming bulb is soft. It takes about half a dozen squeezes to get it hard. I'm just wondering whether it should be hard all the time? (Hence the original question).

I've had the glow plugs out and they're all fine.

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.

 

[Avocet]

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.

Interesting thought! I doubt we've got the wrong one though. We've had the car since 40,000 miles and I assume it was original when we got it. I've had it off several times but can't remember if it is EXACTLY like that. It's certainly "similar"!

 

[Avocet]

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.

Thanks Pete. The kit I bought didn't have that sprocket in it.

 

[Avocet]

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.

I was actually quite impressed with the Japanparts kit. The problem with my OE chain (when I got it apart) wasn't actually with the chain at all. The long, straight chain guide had a bit of plastic snapped off the end and the chain was flapping about. The same guide in the Japanparts kit, had a longer steel section to support he plastic better. So far, the timing chain is absolutely silent.

I have to say that I am deeply sceptical about the notion of a "stretched" timing chain. When I took the original one off, I put a Vernier across as many links as I could (it was a 150mm Vernier - a good quality Mitutoyo one) and then did the same measurement on the new chain. Any difference was in the second place of decimals and very small! Certainly, the hydraulic tensioners projected more, but thinking about it, I feel that is down to wear in the plastic guides rather than any stretch or wear in the chain or sprockets.

I've spoken to Des Marples a few times - an excellent chap! He posted me a BG vacuum pump chain and tensioner (the ones that are on there now) but it's rattling again. not badly enough for me to want to DO anything about it, but there's a bit of a rattle at 1500 RPM.

I don't know whether I can be bothered changing the timing chain AGAIN, to be honest. The car is nearing the end of its life. I'm wondering about slotting the holes in the cam sensor mounting to see if I can move it a little bit to alter the trigger point.

 

[Avocet]

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.

Another interesting though, thank you! Engine is commendably smooth, to be honest, but it won't do any harm to check! Certainly the clutch and DMF are original. it's just coming up to 130,000 miles.

 

[Avocet]

Hard or soft?

I am, of course, referring to the priming bulbs on the T30 2.2 DCI diesels! I still can't get to the bottom of this problem on Mrs. Avocet's car. Go out in the morning, turn the ignition on, wait until the glow plug light goes out, crank it and it fires up, pretty much instantly...

...and then stalls a few seconds later.

It will re-start, without any trouble at all, but then stalls again a few seconds later. If I catch it and hold it at 1500 revs or so for about 30 seconds, it's fine, but idles roughly. After about a minute or two it is absolutely fine. No other poor running symptoms. Temperature DOES seem to be a factor, because on frosty mornings, it will have to be held at about 1500 revs for a bit longer before it will idle.

Now the only time it has ever done something similar, it is just after I have changed the fuel filter. However, after a couple of re-starts, it's fine. At present, when I go out to the car in the morning, the fuel priming bulb is soft. It takes about half a dozen squeezes to get it hard. I'm just wondering whether it should be hard all the time? (Hence the original question).

I've had the glow plugs out and they're all fine.

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.

I'm starting to rule that one out now, to be honest. I think I've been barking up the wrong tree so far. It DOES go hard, and then soft again, but I think it probably will do that anyway. Bleeding from the drain tap won't help because it's at the bottom of the filter housing. It's really only intended to drain any water out of the filter housing.

 

[Colster]

I've also read of people placing a washer between sensor and mounting hole, effectively keepibg the sensor a bit further away from the sprocket.

Another thought. I remember you changed cam sprockets, and I believe these may also be different between di and dci.

 

[leafy]

Weird one as you say once running in the morning it's fine so doesn't sound like a timing issue does it but more fuel(Is Something happening overnight) .Just wondering if once turned off at night you got some mole grips and clamped the pipe just before the primer bulb to see if any fuel was escaping back somehow and see how it starts in morning.You could always do a fuel pump -ECU relearn too .........worth a try.

My daughters has been playing up for 2 weeks with the EML on and limp mode .We changed pedal unit ,wasn't that .........then SCV and Fuel rail pressure regulator (Both from a donor car I had).my son in law did an SCV re-learn from Yorkshire Engine Services video on the Navara for some reason but that didn't work .EML still on and limp mode .Anyway I was stood by Xtrail thumbing through this forum for the pdf of the procedure and it's slightly different from what Des Marples says so make sure you use the Xtrail one you get on here.I said to my son in law do it this way and as soon as he finished the EML went out no more limp mode and one ****** happy daughter with her Xtrail up and in fine form again.This was either the SCV or Fuel pressure regulator.

 

[Avocet]

Well.... I'm not popping the Champagne cork JUSt yet, but.... I think I might have sorted it! The dealer and then Ah2 both got me thinking about the phasing between the crank and cam sensors. On Saturday, I took the cam sensor out - along with the aluminium casting that it sits in. It bolts to the cylinder head with three M6 bolts. I opened each of the bolt holes out to 9mm and then bolted it back on the engine but slid about 1mm towards the FRONT of the car. It started up straight away and idled nicely! This morning, I went out in it and again, it started up fine and idled straight away. Tonight is quite a bit colder so I'll see how it is in the morning!

 

[Avocet]

Well.... I think maybe, we WILL have Champagne with our dinner tonight! Started instantly this morning at 5 degrees C and idled like a Swiss watch.... (a pretty rattly, noisy Swiss watch....)

Many thanks to Ahto for putting me on to it! Of course, I know I haven't actually "fixed" the problem, and maybe the timing chain's days are numbered, but it isn't rattling again (yet) so as far as I'm concerned it's FIXED!

I still can't believe that Nissan's engine management system doesn't have a fault code for "cam and crank sensor signal mismatch" (or something like that)! How do other manufacturers do it? Come to that, does anyone know why it needs a sensor on both the crank AND one of the cams?

 

[Ahto42]

If that trick gives you back the 2ms that is needed to run again, then thumbs up :thumbs:
But i would not recommend it to an unkown or high mileage chain. Avocent has new chains, so unlikly that they are worn near the end of theyr life.

Changing only the upper chain is not a very big job, but stil ltakes time when doing it first time. If you have the tools, skills, confidence and 2 floor jacks, then it is a DIY job.

 

[turny]

Hello chaps,
I had a very similar situation,engine would start but cut out, give if a few revs it would stay running, I put it down to a cheap aftermarket fuel filter and planned on changing it to a decent quality or genuine nissan but never got round to it due to a more pressing timing chain rattle that I could no longer ignore.
So after many hours of investigating on here, advice that was given by members in here, I hatched a plan and carried it out.

purchased a bga timing chain kit without sprockets around £140 as far as i could find out bga didnt do a vacuum chain so nissan genuine vacuum pump chain and tensioner around £105 was also purchased.
Fitted only top chain parts only and vacuum chain and tensioner.

This took me two days taking my time.
The result was the engine was quiet as a sewing machine and the previous cutting out problems no longer occured so I am 100% convinced that the cutting out was due a timing issue and not fuel related (still have the cheap filter on).
Many thanks to the members who gave the advice that helped me on this journey (Avocet and Ahto42).

 

[Avocet]

Great news! Thanks for letting us know! I've often said that the best thing about the X-Trail is this forum! :gathering:

 

[leafy]

Further to my earlier post about getting my daughters car running mighty fine again after changing the SCV for a known spare one I had kept , the other night it had a hissy fit again and went into limp mode and go slow.

She dropped it off on my drive for me to look at.

I thought what on earth is wrong now then I remembered that when my son in law did the job of swapping the SCV (Had a spare one from an engine I broke for parts)over he gave me the original SCV back with an O ring.When I went into my shed to put the SCV back in my spare injector pump there was an O ring in it still :frown:.I asked him if he had put the O ring in when he changed the SCV's over in my daughters xtrail ,he assured me he had.
Me being me had to take the SCV back out my daughters Xtrail and low and behold the O ring was missing.Once all back together with the O ring fitted and a quick relearn/reset the car is running perfect again.An easy mistake but a nightmare if the O ring is left out.

 

[Avocet]

Nightmare! :headbang:

How long did it take you to swap them this time?