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Hi All,

Going to view a GT for sale this weekend but the add states it has a 1.9JTD engine and all the info i can find on the net says the GT (55 plate) has a 1.9JTDm 16v engine, can anyone help??? Does the GT have two versions of the 1.9JTD engine or does the guy selling it not know the difference???

Any info would be much appreciated,

Thanks,
Rob.
 

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pretty sure that this is the same engine. I think they were just badged differently. As far as I'm aware they are all 150BHP units (apart from the very latest 170BHP ones). I've got one, seems a great engine, just make sure the cam belt is changed before 4 years old-see thread on here
 

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there are differences between the multijet and the JTDm, mainly the fuelling side, the later JTDm is far more tunable due to higher pressure pump.
 

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Haven't yet found a definitive answer on JTDM vs JTDm, would appreciate it from someone on here. In fact the JTD development history. There are definitely two different 1.9 JTD engines in the GT, the second has lower emissions. The thing that confuses me (easily done), is that my 156 JTDm, or is it M has 150bhp, 157 CO2 emissions etc identical to the 159, injects fuel several times/stroke and I can't find anything on the interweb to contradict it, but there's been various comments that would indicate that it's a different configuration to the 159 engine. Is the fuel injection system different, compression ratios, engine map. Please be specific, as I thought that my car being the last of the 156s was just 'lucky' to inherit the new engine due in the 159.
 

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I too have one of the last 156 jtd mj with the 150hp engine . Dealer told me at the time it was to be used in the new 159 model and that it was put into the last few 156"s as the 140 was no longer being made.Not 100% sure if he was correct but it seems feasible.
 

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I was under the impression the engine that went into the very late 156 models was the same as the one in the GT that had the slightly higher CO2 emissions.
 

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there are differences between the multijet and the JTDm, mainly the fuelling side, the later JTDm is far more tunable due to higher pressure pump.

That is about it! The newer engine is the multi jet (JTDm) I have got it in mine. Bl**dy good engine. Had it remapped, goes like a 2.4 JTD!!!

Peter
 

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That is about it! The newer engine is the multi jet (JTDm) I have got it in mine. Bl**dy good engine. Had it remapped, goes like a 2.4 JTD!!!

Peter
What year is your GT? Does anyone know the date they stopped using the older 1.9 16v engine and started using the newer one in the GT?
 

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GT - Feb 2004 to July 2005, had 176 CO2s emission, 165 CO2s after that. I assume it was remapped, though might be a different injection system. Last 156s and first 159s have 157 CO2s - same engine? Can't understand why the GT has higher emissions as the engine outputs are the same ie bhp and torque, maybe constraints on induction systems.
 

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B****cks, just realised that that's about the time they switched from single injection to multi injection, that would probably expain the difference in CO2s
 

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Can't believe the 156 and 159 with the same engine have the same CO2 output, the 159 is carrying loads of extra weight..

It wasn't just a remap, the injection system was revised.
 

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I'm not being funny, but are you 100% sure ? Thought emission tests were carried out with the vehicle stationary, so weight wouldn't matter. Even if it were measured on the move the engine would still give the same specific outputs, but as bhp/kg are different the 159 would be slightly slower on 0 - 60
 

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Up until that point there were so many rattles from the tailgate that ppl welded them up. lol
 

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I'm not being funny, but are you 100% sure ? Thought emission tests were carried out with the vehicle stationary, so weight wouldn't matter. Even if it were measured on the move the engine would still give the same specific outputs, but as bhp/kg are different the 159 would be slightly slower on 0 - 60
When testing for the CO2 figures they are tested on a rolling test bed. Which is why things like skinny tyres and longer gear ratios are starting to appear on 'Eco' models. CO2 output and fuel consumption figures are highly correlated.

MOT emissions tests are done at idle and fast idle, both without load on the engine.
 

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So, are the last 156 JTDms the same as the first(current) 159 JTDms, definitive answers only, with specifics ?
 
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