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JTS experience

4K views 66 replies 17 participants last post by  piedthepiper 
#1 ·
Hi, I have been a forum member for many years and read the comments with great interest. I have thought that the balance needs to be restored on the JTS engine debate. First a bit of recent history, some years ago I bought one of the last 155's 2litre TS, new, what a wonderful car, I would probably still have it for for the fact that I wrote it off. I did try to buy it back, but the insurance company refused. It was followed by a 156 V6 (Autodelta), a wonderful car that I loved but retirement and rising rule costs meant it had to go. I bought a '54 facelift JTS. Now to be honest my initial feeling when driving it home (ebay buy) was one of disappointment, but I loved the look of the front. Also on the way home the EML come on, following a misfire, you can imagine my dismay, however, I decided that the problem was caused by the engine being steam cleaned and it was damp. I did the usual checks on connections all seemed OK.
The car settled down but every now and then the EML would come on and there was a slight misfire, also the tick over was random and there was a hesitation at low revs. I replaced the MAF, no difference, thermostat, because I don't believe they last forever and then I bought a set of used coils as one of mine was dodgy, mis-fire was now cured, but the tick over was still not great.
A tin of BG44 was purchased and I am convinced that it made a difference, they do say that it takes a while for it to work so it is sometimes hard to recognise the improvement. The other thing that I did was to stop using super market fuel and use a proprietary brand. The car covers about 4-5k miles a year and many of those are on the continent, but again I try to use "garage" fuel. Recently the car has been running better, livelier, I thought. I noticed that it was also noisier but no sign of a blow tho'. However the flex at the front was leaking slightly and I decided that the back box although looking very rough was sound but the internal baffles were shot, hence the slightly nicer sound. I bought a supersprint back box and a new flex, strangely the tick over and hesitation was again slightly better but the sound was disappointing. Although the car has a full service history and the belts were not really due I decided it was time to do the belts and variator, which was a little noisy. I also purchased a set of C&B middle road cams. I fitted this lot last weekend and I am more than happy with the result, the engine seems more responsive and smoother, the power comes in with a little more determination and it is quieter, probably due to the Variator. The car now feels great, I am far happier with it, my impending trip to the dark continent will be the final test. What I do believe is the use of "good" fuel is very important, the tick over is now rock solid.
Interestingly, the car still pulls from very low revs, i.e. just above tick over.
There is hope for the JTS, was looking for a diesel GT but now I think my next buy will be a GT JTS.
Sorry to drawl on but I hope it helps to redress the balance very slightly.
 
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#2 ·
Diesel in an Alfa, seems wrong I know.
I bought my diesel because VED is lowest and the MPG is highest. Purely for economy then.
I got my GT cheap because it is a CAT D, probably the same I'd have paid for a JTS.

The guys at Mangos seemed to suggest the JTD was the best 'all rounder'. I'm not dissapointed but for the idle racket :lol:
Already noticing the difference in fuel costs switching over to this Audi. Mind you apart from going upto see SteveW over the weekend I never went anywhere really or so I thought. I did 150 miles doing not really much :D
 
#9 ·
I have just bought my neighbour and best mate's 05 156 JTS from him and was a bit dubious about the engine too. He had the car for a year and in that time he fitted a new radiator and fuel pump but otherwise the thing has not missed a beat. Now I have it I am repairing the aircon but otherwise I am hoping to do little or nothing to it. It had belts at 70k but I have no idea if the injectors have ever been looked at - it now has 86k on the clock.
Having owned numerous Alfas before and coming from a 145 QV I found the JTS noise a bit disappointing but it's not that bad. The low end torque is massive in comparison to the t spark and the JTS seems to be returning 32-35mpg for me, while the t-spark struggled to hit 30 (I know it was a different car but I think the comparison is valid).
I hate diesel with a passion....horrible smelly tractor fuel.....the only reason to ever own a diesel is to save money and having owned several diesels (and drive them at work) I've decided life is too short so I will never own another!
 
#12 ·
I absolutely agree with your comments re: sound torque mpg, As trashbat says a good injector cleaner is a good idea, I also believe that good fuel is a must. Diesel, well yes I agree but cost is figuring more and more, although I am thinking about going down the LPG route.
 
#15 ·
On the GT the 2.4 was never an option (147 also I think). However, I witnessed it in a Brera. Unlike my 4 pot oil burner, when given the beans not only did the 2.4 go like nothing else, it actually sounds rather good too.

I don't think anyone is really diesel bashing, just commending the JTS ;)
 
#20 ·
Q: How do you know if someone owns a diesel?

A: They tell you about it, loudly.

Q: How can you be sure if someone owns a diesel?

A: They argue with you about it, loudly.

Q: How can you be absolutely certain if someone owns a diesel?

A: CLATTER CLATTER CLATTER BELCH BELCH CLATTER CLATTER
 
#22 ·
I really wasn't looking for a fight with diesels or for this thread to turn into a war.....I just don't like them. They do produce good low down torque which is something the JTS does well and whilst I loved my 145 QV it lacked that urge at the bottom end that my previous 166 3.0 V6 had or even the modern diesels I drive at work......the JTS engine goes a long way towards bridging the gap between the top end zing of a T-spark and the low down grunt of the V6 or a Turdo diesel. Shame that it doesn't sound like the V6....now that's a beautiful noise.
 
#24 ·
You started it.


Anyway.
Yes the JTS on paper does seem to have good proven points that seem like a good halfway house between combining the good aspects of both. Uses similar tech to the Diesel common rail but using petrol (Obviously at a much lower pressure). But direct injection is a step forward.


Fortunatly Alfa / Fiat group decided to go a step further with petrol tech and emision by bringing in Multi air. Or an variable intake valve opening. Which again improves the combustion cycle again.

I'm suprised that they never looked at putting the same on the exhaust side. But I guess the affect of it will not be as great as the intake side. Also I imagine space and the expense of the engine manufacture would be a lot for an extra 5%.

To be fair all internal combution engines are a bit draconian compared to Electric.


PS. I think you should always decide on the engine type by what type of commute or use you have for the car. Not just only on preference.


If I did long motorway journes I'd opt for a diesel or LPG car with large fuel tanks

Short journeys at peak times then petrol

Fun only or track days V6 / V8 petrol


PS I think the Fiat group make the best diesel engines going. Even if they are a little fragile.
 
#25 ·
I love my JTS to bits! :) Although I've heard a few horror stories from owners of earlier models, the later ones by-and-large seem great. After all, this is a forum, and most people only post on forums when they've got a problem, so you don't often hear of the good 'uns. She gets serviced around the 5000 to 6000 miles mark, good quality 97 / 99 fuel, the correct fluids, all levels checked every weekend even though I only do about 4000 miles a year (live just down the road from work). She returns around 34 mpg and in the two years I've had her, has only needed a new flexi section, discs and pads all round (EBC Ultimax), and a set of new tyres recently (Goodyear Efficientgrip Performance). She's just had some Wynn's Direct Injection Power 3 through the intake and the same injection cleaner fluid in the tank, which seems to have helped a bit.

Go JTS! :thumbs:
 
#32 ·
The JTS engine and all other makes with direct
injection need low or zero sulphur fuel.
Shell V power is just that !
All so called JTS engine problems come
from cheap sulphur rich fuel !
 
#33 ·
... the Diesel bashing is funny since the last
couple of Le Mans 24hr races are won by...
Diesels.
(I will never buy one because in Holland
you pay double roadtax on Diesels)
a 156 diesel will cost you 100 euro monthly
on roadtax !!
 
#35 ·
The rules at Le Mans were fixed in favour of diesels some years back and they are only just rectifying things now.....which is why Audi (who incidentally have an F1 style budget some way ahead of their rivals) only just won it this year. It's also worth noting that the Audis sound **** just like their road counterparts!:lol:

BACK ON THE JTS - I don't think just upgrading the injectors will work - the injectors are only part of the fuel supply chain - the ECU needs to know about the big injectors in order to make gains. The only way they would make a difference on their own is if the current injectors were struggling to supply the necessary fuel.
 
#37 ·
On a general note, I have had my JTS for over 3 years and it has been trouble free. One of the first things I did was fit a custom-made MIJ SS exhaust which improved the delivery and the noise. I use V Power as much as I can (the difference is noticeable) and Forte injector cleaner every 4k miles or so. I also had a Terraclean done recently and that made a difference. It's done 80k miles and has never missed a beat, and with the FSD/Eibach combo the handling is superb. The only thing that bugs me a bit is the 5-speed gearbox, but I can't blame the engine for that!
 
#39 ·
JTS sulphur free fuel

On a general note, I have had my JTS for over 3 years and it has been trouble free. One of the first things I did was fit a custom-made MIJ SS exhaust which improved the delivery and the noise. I use V Power as much as I can :thumbs:
**************************
(the difference is noticeable) and Forte injector cleaner every 4k miles or so. I also had a Terraclean done recently and that made a difference. It's done 80k miles and has never missed a beat, and with the FSD/Eibach combo the handling is superb. The only thing that bugs me a bit is the 5-speed gearbox, but I can't blame the engine for that!
Wilbur G

just confirmed the case !
 
#38 ·
Well when I started this thread I did not expect the discussion to become a diesel v petrol feud.
No offence to anybody, you pay you money and make your choice.
Anyway, after reading through the comments there are a couple of things I may well do. I have thought for a while that the maniverter is a bottle neck, so I think I will change that for an "ordinary" one and place the cat in the original location, I will have to fiddle with the sensors to get them in and then see about a remap, just to try and make the best of the mods.

As an aside, I have just been reading about Terraclean, has anybody got experience of this system. In theory it is a gift from heaven for direct injection engines ( just realised DIE), almost seems appropriate.
 
#41 ·
I would like to try the JTS version of my diseasel GT
But general consensus on here is rather negative against the 2.0 JTS (maybe just in the GT??)

I had a go of a petrol car a while back and was scared to rev it over 4k rpm, in case it broke lol. Thats what diesel does to you.
 
#42 ·
Alfas tend to have quite aggressive factory Cam's. They don't even start to come alive untill after 3k. You are only just hitting peak torque at those rpm's.

I too would like to try the JTS just to see what the engines like. Mainly to see how much additional torque it has over the standard 2.0l TS.
 
#49 · (Edited)
I was lucky enough to have my current 156 JTS and my old 145 2 litre t-spark at the same time and can confirm the low end torque advantage is considerable in the JTS's favour. Both cars are similarly geared I think, but its possible to drive the 156 round (and its a much heavier car) at 35mph in 5th gear whereas the 145 would stall at the same speed and gear. The T-spark only came alive at 4000+rpm whereas the JTS pulls from about 2500 and really goes at 4000rpm.....and its all torque.
 
#43 ·
Great write up :)

I've had my JTS for 7 years and never had a problem with it. I know the cranks made of cheese, and the inlets clog up.. but every engine has its quirks :) A good Italian tune up always smooths things out.
 
#45 ·
I purchased a JTS GT 6 months ago. I really like the torque and have no problems. It's a '57 and have now done 4k. Gennaro is now on 41k.
Joined the forum and then read about the JTS problems and pooped myself and wondered what I had done. But having read many threads it appears to me that it's the early engines that are a bit more suspect.
I use Mobil 1 10w/60 and top up every couple of weeks and notice it always runs better.
Mind you, the info on here is great and I'll move onto Shell V power and put some injector cleaner in to be doubly sure.
Only gripe I have is not much puff past 5800 rpm and it should have come with a six speed box. Mind you, at a steady 60/65mph on the motorway and reduced revs would it have been capable of nearer 50mpg and embarrassed the diesel engine with six speeds?
All the best.
:D
 
#51 ·
The 1.6 TS for a 1600cc engine is fairly nippy. But needs to be stirred. Its the one I have and although its very smooth even in 5th gear at 20mph (mainly down to gearing) it lacks the torque delivery.
the 1.6 feels highly strung for an N/A road car. The 2.0L feel faily detuned in comparison. There's plenty more to unleash I would imagine.

The JTS in my mind is an improvement and with all the niggles the TS does have least the torque is substantially up. Which as others have said I still think the 147 / 157 and GT are still fairly weighty. The engines before had been in much lighter cars.

I've often wondered what the 145 would be like with the TS engine. As the engine itself is good. Its just the weight that hurts its performance.

Still least on a run even my poop 1.6 will acheive a true 42mpg.


Shame you never got the 2.2 JTS in the 156. Think that would have been a decent mover.
But then again you would argue why have a JTS with a similar output to the 2.5 V6.
 
#52 ·
Shame you never got the 2.2 JTS in the 156. Think that would have been a decent mover.
But then again you would argue why have a JTS with a similar output to the 2.5 V6.
Not much point, I guess. Different engines too, the 2.0 JTS basic engine being an Alfa, and the 2.2 JTS being General Motors (Vauxhall).

I'd like a V6 as well, they seem cheap as chips at the moment.
 
#53 ·
Indeed I keep jostling with the idea of selling the 1.6 and getting a older 156 with the 2.5 Busso engine.
Mainly becasue it will be similar running costs and no more on insurance. The 156 is the only one that falls in my available bank.

Still think the JTS is a good move. Just some more added woes if you do get the dreaded injector issues. Although they can be avoided with preventative maintenace.
 
#56 ·
Having had 2.0 TS and JTS 156s, I can confirm that in my opinion and experience the JTS is torquier and about 10% more economical (possibly because of the better torque). Felt a bit smoother at most speeds, too - though I agree that you probably don't rev a JTS like a TS.

I've also had 1.6 and currently a 1.8 Sportwagon - both of which are OK although the 1.6 is a little lacking in sparkle - the 1.8 of course at only 10 bhp less than a 2.0 TS and arguably free-er revving isn't a bad compromise, but I don't think there is any mpg benefit from the smaller engines in the same shell. I've also got a 2.5 V6, and have had a 2.4 JTD - both wonderful in their own way - the V6 with its sound and willingness, the 2.4 JTD with its wall of torque. I'd argue that the V6 could cope perfectly well with the 5-speed box, whereas the 2.4 could make good use of the 6 speed - with a lower ratio diff, of course, for cruising excellence. Not tried the 1.9 JTDm in a 156....must get one ;)

I think the fairest conclusion is that most of the engines have their strengths, depending on what you need them for. My mate Paul (Afor Alfa) hates JTSs with a passion, though, and I'm sure he must have his reasons!
 
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