Anyone understand JTD injector codes?

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Anyone understand JTD injector codes?

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Hi All, Hope this is the correct place to post this query.
I have an '06 Multipla JTD Multijet.
Having some starting problems, it never failed but it is sometimes difficult.
Anyway, some say that it could be injector problems so I was looking at the injectors with MultiECUscan.
Three of the injector codes are similar and one appears different - see image.
I checked and the codes on the injectors match what is seen in the software.
I wonder if someone has changed an injector and put in an incorrect one? Maybe one from a non-multijet?
Even if they did, would this cause slow starting and rough idle?
Thanks for your input.
 

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Hi All, Hope this is the correct place to post this query.
I have an '06 Multipla JTD Multijet.
Having some starting problems, it never failed but it is sometimes difficult.
Anyway, some say that it could be injector problems so I was looking at the injectors with MultiECUscan.
Three of the injector codes are similar and one appears different - see image.
I checked and the codes on the injectors match what is seen in the software.
I wonder if someone has changed an injector and put in an incorrect one? Maybe one from a non-multijet?
Even if they did, would this cause slow starting and rough idle?
Thanks for your input.

Hi,
I've not got an answer.. but am sure this kinda thing has been covered plenty in the past.., (y)
Charlie
 
If the wrong injector is fitted, it will run incorrectly immediately. But you don't say whether this issue is recent, or immediately on buying the car, or has developed.

The codes relate to minor differences in manufacture. The software uses this to regulate the injection time to compensate for the differences. When injectors are replaced the software needs to be told, then the ECU will adjust accordingly. What you are looking at it just a record of the codes, and does not itself indicate any problem.
 
@DiamondDave
When is it hard to start, Hot? Cold? If it's cold, glow plugs are more suspect.

Robert G8RPI.

It starts fine when cold, and the glow plugs kick in a bit - they aren't working correctly. It starts fine when up to temperature. It's a bitch to start when in between. I read an interesting post where avionista blames the fuel pump (not HP pump) pressure regulator not bring the fuel pressure into the HP pump at a high enough pressure soon enough – as well as a sticky valve inside the HP pump…..
https://www.fiatforum.com/ulysse/342528-2003-2-0-jtd-cold-starting-problem.html
I tested this theory this evening leaving work.
It was 22oC (lovely weather here in Eire at the moment!), and had I cranked the engine after the glowplug light had gone out, then it would have turned and turned before starting.
Instead, waited until I heard the fuel pump in the tank stop, then cranked and it started as good as when hot. So, I think there is something in that alright.
 
If the wrong injector is fitted, it will run incorrectly immediately. But you don't say whether this issue is recent, or immediately on buying the car, or has developed.

The codes relate to minor differences in manufacture. The software uses this to regulate the injection time to compensate for the differences. When injectors are replaced the software needs to be told, then the ECU will adjust accordingly. What you are looking at it just a record of the codes, and does not itself indicate any problem.

I suppose the reason I asked is that one of the codes appeared completely different to the other three. It drives fine, but at low RPM (1500 - 2500) when I accelerate it sounds a little like a VW Beetle or Scooby - boxer engine. Originally I suspected an EGR valve, and while the first one was leaking a bit, replacing it didn't cure this noise. That's why I suspected an injector, at low RPMs the multijet does several injections. If a standard JTD injector were fitted, maybe it couldn't handle the multiple injections and act up. I've put a bottle of Wynns injector cleaner into half a tank in the hope it might help
 
It starts fine when cold, and the glow plugs kick in a bit - they aren't working correctly. It starts fine when up to temperature. It's a bitch to start when in between. I read an interesting post where avionista blames the fuel pump (not HP pump) pressure regulator not bring the fuel pressure into the HP pump at a high enough pressure soon enough – as well as a sticky valve inside the HP pump…..
https://www.fiatforum.com/ulysse/342528-2003-2-0-jtd-cold-starting-problem.html
I tested this theory this evening leaving work.
It was 22oC (lovely weather here in Eire at the moment!), and had I cranked the engine after the glowplug light had gone out, then it would have turned and turned before starting.
Instead, waited until I heard the fuel pump in the tank stop, then cranked and it started as good as when hot. So, I think there is something in that alright.


are you saying the tank pump is still running in cycle , AFTER the glow lights have gone out..??,
pretty sure mine ( marea 100 JTD) is well short on the pump..'less than 5 seconds:confused:

have you checked the fuel filter..??

Charlie
 
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are you saying the tank pump is still running in cycle , AFTER the glow lights have gone out..??,
pretty sure mine ( marea 100 JTD) is well short on the pump..'less than 5 seconds:confused:

have you checked the fuel filter..??

Charlie

The pump does seem to run longer that I would expect, it probably times out rather than stopping at a pressure limit.
I tried it again this morning - ignored the glowplug light going out and waited for a further 10 seconds, the glow plug light started flashing to say there is a problem with the plugs, then cranked it and within 3 turns it started fine.
I'm beginning to become more convinced it is a fuel issue and not the plugs.
 
As suggested above, check the filter. Has it been replaced at the specified times? It collects water and should be drained regularly, excess water will cause all sorts of starting and running issues. A restrictive filter will prevent the required pressure getting to the injectors, making the pump work harder and for longer.
 
Filter was changed only a few thousand K ago. There was no sign of any water or dirt when I changed it that time either.
I think the diesel injector cleaner is helping with the boxer engine noise. Must try another bottle from a different supplier in case they have different solvents etc.
 
Next step would be a pressure test. The pressure gauges are expensive, so not usually viable for home DIY. You'll need to find a local garage that will do it for you.

If pressure low, possibilities include:
Failing pump
Failing pressure regulator. A quick test is to crimp off the return pipe, so allowing the pump to attain full pressure. First, with engine stopped, pump should run for a shorter time if the pump is good. Then with engine running, crimp the pipe and see what effect it has. Be prepared to let go quickly. May need to turn off engine promptly, so have help.
 
Hi All, Hope this is the correct place to post this query.
I have an '06 Multipla JTD Multijet.
Having some starting problems, it never failed but it is sometimes difficult.
Anyway, some say that it could be injector problems so I was looking at the injectors with MultiECUscan.
Three of the injector codes are similar and one appears different - see image.
I checked and the codes on the injectors match what is seen in the software.
I wonder if someone has changed an injector and put in an incorrect one? Maybe one from a non-multijet?
Even if they did, would this cause slow starting and rough idle?
Thanks for your input.

You should match the oem part numbers of the injector with the engine number and install as per the manual.

Then ......

If the injector requires coding via Examiner perform this action, not all injectors need coding as it depends on engine variant etc etc,
the codes tell the ecu the injectors individual fueling parameters so it can give the correct pulse timing.

Also with coded injectors you can isolate them electronically in the Examiner for testing-fault finding purposes.

:)

If the starting problem is from cold only check battery and starter motor are 100%
leak off pipes, glow plugs, temperature sensor.

If the starting problem is from hot check the starter motor isn't shorting (hot),
the crankshaft sensor is ok, fuel filter housing for air leaks.




.
 
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