Use of Memory Clear and Diag Check for ECU Errors instead of MUT/OBD

Another quick up date with this issue and the pump has been back to the reconditioners only to be told it is in excellent working order.
I did a journey to Scotland prior to removing the pump for the third time and had no issues with it going into safe mode at above 2000 rpm and behaved itself for 90% of the journey, once back in traffic it is back to safe mode, so any revs between 800 rpm and 2000 rpm it is safe mode but not every time.
Code again throws up 2 long and 3 short blinks. Every electrical component, exhaust system, fuel lines and tank have been replaced or renewed, wiring done, ecu, injectors, oil, all filters so now after the pump done there is nothing left to check or replace, and it is no better and now 5 diesel mechanics what else can it be but unrepairable.
However I have come to the conclusion along with my son that it could be a possibility that the timing chain tensioner is losing some pressure at lower engine speed causing the timing chain to slacken altering the timing?? Who knows but it has got to the stage now that I have spent so much on this lorry and all the so called experts with all their fixes that I have got to the stage that I might just have to run with it in safe mode until whatever the problem is finally raises its ugly head and something breaks, then we'll know what it was! I have been doing this for the last 5 years, its still not broken!
Is there any chance that someone has a wiring diagram for my Canter, nobody in the UK has one, not even the main dealers? I know as I have tried.

Peter
 

biggoolies

Adventurer
Since you have done almost everything to fix this. Is it possible you have some problem with the ECU itself or a faulty wiring harness to the ECU or it not seated properly?
 
Hi biggoolies, thank you for your reply.
The ECU was sent away and was returned with no faults, refitted it and the problem was still there. I purchased a second hand ECU just to satisfy myself and that too when fitted didn't eliminate the problem. The engine bay wiring harness has been reconditioned. I haven't replaced the wiring harness to the ECU, although that was checked by the auto electrician.
I have refitted the pump and never got a chance to start it. Yesterday morning I finally got it running and idling, unfortunately I have got the timing slightly out as it wont rev passed 3000 and will only restart on easy start, I will remove the pump again to reset it correctly :eek:
I will look at fitting a new timing chain and if this doesn't sort the problem the only thing left to do is get a delete program done to the ECU for the safe mode. Hopefully that won't be necessary but last resort.

Peter
 
Sorry if this has been asked before or there is another thread to use, but my next issue is trying to locate the correct timing chain kit for the 3.0 4M42 OAT engine. I have tried many suppliers here in the UK and have had no luck finding one. As I have replaced every electrical part and engine bay wiring the lorry is still going into safe mode when it feels like it and throw up code 2 and 3 on the blink code which has been established as the camshaft timing sensor. We now are going to replace the complete timing chain and everything that is timing related but as I have come to a blank finding such kits I am now looking at overseas suppliers. Any help here would be much appreciated.
After searching the forum I have come across a possible source in Australia.
Does any one know if the 4m40 engine timing chain kit is the same as the 4m42 timing chain?
I can't seem to email the company as email comes up as disabled for Bretts Truck parts.
I have also found Bruckner Truck, which I was able to email.

Regards Peter
 
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PKDreamers

Adventurer
Peter .
No worries mate, hope then new timing chain kit fixes your problem/s.
Be a good idea of a few photos to show people what you have to do to change the chain.
 
Good call Pete, timing chain ordered from SMSdiesel. They were the only firm to get back to me and were able to supply from the Ireland branch.
I should have it shortly.
I wont be doing the job myself, trusted it to the Mercedes mechanic. I'll ask him if he can photo any details.
Apart from the obvious bits to remove like Radiator, rocker cover, crank pulley and front timing cover, it'll be the more technical stuff like timing the engine first and the procedure which follows to actually remove and refit the chain and all the new parts in the kit which will be more beneficial. There might be the chance that I can assist with the change which would be better too. I will certainly asked him.
I too hope that this will sort the issue.
Peter
 
Just an up date, the lorry goes in for the timing chain kit replacement on the 20th and fingers crossed the kit will fix the safe mode issues, I sure hope so as there is nothing left to change :)
I will keep you posted.
 
Do we have success with the lorry now or not, time will tell, but as promised I am reporting back on the on going saga of the mysterious safe mode issues.
Drove to the mechanics yesterday and we started to remove the radiator and fan, then on to a few water pipes including the EGR Valve and pipe. This then exposed what I thought was the front cover, turned out to be a sound deadening attached with 4 bolts, once this was removed and a quick examination we discovered that it looks like the cylinder head and sump have to come off to change the timing chain which would turn into a mission!.
On further investigation of the sprockets, chain and the guides, there was absolutely no sign of wear to any of these parts whatsoever. However on explaining to the mechanic the symptoms we were experimenting with the lorry and what I thought was the tensioner loosing tension which in turn could send a signal to the ECU of a timing fault we looked into timing the engine and then removing the tensioner. By doing this it has revealed that the chain kit must have been replaced fairly recently as there were still man made white dots poorly applied to the sprockets. ( The mechanic said this engine might have had a lot of work done on it which would be the reason it so clean and runs so well and is an exceptionally quiet running engine) So we changed the tensioner with the new one out of the kit, reassembled everything again and so far after 60 miles the lorry hasn't gone into safe mode. When we checked the old tensioner it seems like the ratchet teeth are worn and you can simply press the thing with your fingers in and out, but can't do that with the new one.
We are keeping our fingers crossed that this is the last of the problem regarding the intermittent safe mode mode?

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kerry

Expedition Leader
That would be good news. What was it that made you suspect it was related to the timing chain? It’s not clear to me how a loose timing chain would effect timing. Isn’t the timing controlled by the tooth placement of the chain which would remain the same whether or not the chain was tight or loose?
 
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Aussie Iron

Explorer
That would be good news. What was it that made you suspect it was related to the timing chain? It’s not clear to me how a loose timing chain would effect timing. Isn’t the timing controlled by the tooth placement of the chain which would remain the same whether or not the chain was tight or loose?

A slack adjuster would let the cams " bounce backward and forward " (think valve spring pushing back on the cam) on the slack of the chain. And yes, even at the speeds they are rotating. Would this cause sensors to tell the ECU there is a problem. Probably. I'm certainly no expert on the problems of computerized engines but that would be my take on it. Yes tooth placement in chain controls timing but it doesn't stop it slopping around.

With chains running on sprockets on machinery in general the faster they rotate the more they flail around. That is why chain adjusters are needed on the slack side.

Dan.
 

kerry

Expedition Leader
A slack adjuster would let the cams " bounce backward and forward " (think valve spring pushing back on the cam) on the slack of the chain. And yes, even at the speeds they are rotating. Would this cause sensors to tell the ECU there is a problem. Probably. I'm certainly no expert on the problems of computerized engines but that would be my take on it. Yes tooth placement in chain controls timing but it doesn't stop it slopping around.

With chains running on sprockets on machinery in general the faster they rotate the more they flail around. That is why chain adjusters are needed on the slack side.

Dan.
I can see that. What sensors would detect it?
 
That would be good news. What was it that made you suspect it was related to the timing chain? It’s not clear to me how a loose timing chain would effect timing. Isn’t the timing controlled by the tooth placement of the chain which would remain the same whether or not the chain was tight or loose?

After every electronic component was replaced by several different experts, and nothing left, the blink code kept throwing up timing sensor fault. Even after it was cleared.
This intermittent problem of the lorry going into safe mode seemed to do it mainly when it got up to normal running temperature and any speed under 2000 rpms. If I drove it on the highway it seldom dropped in to safe mode, but as soon as I slowed ie. Off the motorway and onto a slower moving road it'll go into safe mode, which to me was engine speed related. It would also drop into safe mode at any speed for a period of 2 seconds or more which just made it so ill regular. At times driving along the road it would drop into safe mode, and getting a bit frustrated I'd switch off the ignition while on the move, switch the ignition back on and crash start it, I might get 100 metres, or 5 miles before safe mode again, other times I'd just depress the clutch pedal down so the revs dropped to idle, the EMI goes out and it's good again. So it had to be timing related and the only thing that hadn't been done was the timing chain. I also just started thinking how the system works and decided that if the tensioner was losing tension this could cause a very slight blackness in the chain, which could be picked up by the crank sensor, or cam timing sensor which is in the pump, sending it into safe mode. The tensioner is oil pressure fed and has teeth and a lever mechanism that applies tension on the chain. I just really was guessing when I mentioned this to the mechanic, but he said it sounds logical. So through this great forum I was able to locate a timing chain kit. As you know it wasn't going to be fitted due to it being a fairly major job, so we opted to just fit the tensioner.
So far so good, haven't had it going into safe mode......yet.
Will keep you posted
 

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