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Discussion Starter #1 (Edited)
The idle of my newly acquired 2.4 jtd is not what you'd call smooth, its trying to shake my fillings out when stationary!

If you breathe on the throttle or take the rpm up by 50 it is very smooth if this helps

Fuelling issue?

Did a search but couldn't find anything similar
 

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if it was engine mounts i would have thought be doing it at any revs and probably be noisey on acceleration and deceleration
Mine certainly doesn't miss but is rough on throttle, smooth on cruising. Polo I had previously even worse on idle but smoother at other all times was cured with a gearbox mount.
 

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Discussion Starter #7
Engine is super smooth and powerful except on natural idle speed

I assumed it must be fuel as touching the throttle cures the vibration instantly

It starts well hot or cold, smokes a little on hard throttle (black) but thought normal for a dirsel

It's almost like it idles on 4 cylinders?
 

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Engine is super smooth and powerful except on natural idle speed

I assumed it must be fuel as touching the throttle cures the vibration instantly

It starts well hot or cold, smokes a little on hard throttle (black) but thought normal for a dirsel

It's almost like it idles on 4 cylinders?
take plugs off and clean injector connections possible poor connection , you can wiggle them to see if engine note changes
 

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Discussion Starter #11
I gave the ecu reset and checking the injector plugs a go but had no joy

If I get a vag com cable will it let me interrogate the ecu to see if all injectors are working at the same level?
 

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I suspect it will but there are various readings as each injector has an individual adjustment depending on it's unique number. I am describing this poorly but I think each injector leaves the factory with slightly different delivery quantity (manufacturing tolerances) and that is adjusted on the ecu when the injector is fitted. I would go and connect FES to my 159 and have a look at the readouts etc. but it's wet, cold, I'm on my 5th Southern Comfort and my wife would kill me!
You will need the software for an airbag reset eventually, usually after someone moves the passenger seat on it's runners as that is enough to cause the connector under the seat to go high resistance and give an airbag failure light. Get the leads and the software now.

Also definitely worth trying what davealfa11 said:-

throw a can of injector cleaner in with shell v power.

I would use half tank of fuel and full can. That is more than the manufacturers suggest but it worked for me. Can in first then immediately top up as that mixes the cleaner and diesel together.
 

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Discussion Starter #13
Also definitely worth trying what davealfa11 said:-

throw a can of injector cleaner in with shell v power.

I would use half tank of fuel and full can. That is more than the manufacturers suggest but it worked for me. Can in first then immediately top up as that mixes the cleaner and diesel together.
did you have a lumpy idle issue also?
 

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Discussion Starter #14
Just tried removing 1 injector wiring plug at a time to see if that helped pinpointing the problem.......removing the wiring plug on any 1 injector made the idle worse and brought up a "motor control" fault
 

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156 2.4 10V yes, startup, + tickover poor.
Did both ecu reset and injector additive.
Did removing the connectors have an equal effect on every injector? If one was worse than the rest it could be pointing to that injector.
Personally I think you may have a problem with one of the other sensors though. I am not enough of an expert to suggest which but I would get a copy of FiatECUScan (FES) a KKL lead and adaptor set and then go through the various readouts.
By the way what age is it and is it a 10V or 20V?
 

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Discussion Starter #16
156 2.4 10V yes, startup, + tickover poor.
Did both ecu reset and injector additive.
Did removing the connectors have an equal effect on every injector? If one was worse than the rest it could be pointing to that injector.
Personally I think you may have a problem with one of the other sensors though. I am not enough of an expert to suggest which but I would get a copy of FiatECUScan (FES) a KKL lead and adaptor set and then go through the various readouts.
By the way what age is it and is it a 10V or 20V?
Mines a 2003 10v

Every injector had the same effect

Startup on mine is fine hot or cold
 

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If it has had the injectors replaced or fiddled with then Kandlbarrett is right. It is necessary to enter the trim code which is unique to every injector and should be stamped on the injector itself at the factory.

If somebody has moved or replaced the injectors without telling the ECU the new trim code then the engine will run unevenly. It is possible to update the trim codes with the free version of FiatEcuScan FiatECUScan - Fiat, Alfa, Lancia ECU Reader / Scanner

You will have to find the trim codes on your injectors and compare them to what is stored on the ECU to see if they agree
 

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Discussion Starter #18
If it has had the injectors replaced or fiddled with then Kandlbarrett is right. It is necessary to enter the trim code which is unique to every injector and should be stamped on the injector itself at the factory.

If somebody has moved or replaced the injectors without telling the ECU the new trim code then the engine will run unevenly. It is possible to update the trim codes with the free version of FiatEcuScan FiatECUScan - Fiat, Alfa, Lancia ECU Reader / Scanner

You will have to find the trim codes on your injectors and compare them to what is stored on the ECU to see if they agree
Will this require injector removal?
 

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If every injector had the same effect then I don't think that it is an injector issue. I think you need to look elsewhere. It could be one of the other sensors MAF or MAP - take each one out and clean it with carb cleaner. It could be a split vacuum or breather hose check very carefully.

Thought: It could also be EGR valve sticking. Blank it off (some people make a blanking gasket from a cake tin) and see what happens. With a 10V I don't think it will even cause the engine management light to come on and you can leave that piece of junk blanked for ever after.

When you have fixed this issue you MUST get it remapped. Being in Dorset you could take it to Auto Lusso Bournemouth; let Lawrence fix the current fault and remap it at the same time. Late Christmas present!

Also did you do a full engine ecu reset without cutting corners; battery disconnection 45 mins and 90 secs in appropriate key positions and DO NOT touch throttle for 15 mins once started!
 
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