In used Jettas I have a choice of the 1.9 105bhp engine and the 2.0 140bhp. They are different engines apparently, and the 2.0 shoudl be more modern. So how come it's so much less economical? Surely to drive a certain speed you inject a certain amount of fuel (in a diesel) regardless of how big the cylinder is? Surely, at a constant 70mph those two engines must return the same fuel economy since the weight difference must be negligible.

What gives?

the 105bhp diesels are suitably flat as a fart. 140bhp is not only more displacement, but more turbo boost, more boost needs more fuel. and the gearing is different, e.g at 70mph one might be doing 1500rpm one mine be doing over 2500rpm! different engine needs different ratios to work with its setup.

Dad works at skoda main dealers (came from 25yrs of vw experience) and to be honest the 2.0 140bhp is probably the best of the diesels.

more boost needs more fuel

No – more fuel needs more boost. You set how much fuel you want with the accelerator, and the ECU makes sure enough air is in there to burn it all.

Oh.. just worked it out – it's the 7-speed DSG version of the 1.9 that's more economical – must be the extra gear…

Pinches sums it up well but having owned Octavia's with both of these engine's buyer beware if they are on variable schedules. The turbo's on the 2.0 have a much greater potential of going bang due to the extended oil changes – best case scenario is a new turbo and cat, worst case is a complete engine being needed. If you can, try and buy one which has been on a fixed schedule.

Do they not go a Jetta with the 1.9 pd 130? that engines amazing! think they do it in a Bora

No, that's been replaced by the 2.0 I think.

Also, the plastic water pump impeller blades on the 1.9pd are prone to go, get it swapped at the same time as the cam-belt change, to a metal impeller blade version.

6th gear on 1.9 tdi's is prone to failure on 130/150 bhp versions as well. It's normally the selector that goes but it drops into the box and damages other stuff.

Both 105 and 140 are TDI versions of the engine not PD engines sadly.

there are two versions of the TDI one has DPF filters DO NOT GET THIS VERSION. DPF's costs a bomb should they go wrong and they also effect the fuel economy of the car.

the 140 has to meet euro 4 standards this means lower CO2 output and diesel particulate filters. This reduces the power and lowers the MPG/

"some" of the stuff above is true (the water pump issues). but this only effected the 1.9 PD engines not these 105/140 TDI engines, the issue was fixed by this time.

The 140 is not the best, it's maybe the better TDI engine but and true VAG-holic knows the 130 PD engine is the best/strongest engine

The 170bhp edition are actually being de-tuned by VW due to DPF issues (getting lights on the dash due to the DPF getting over coked with soot, google search we have members on our forum returning cars to VW and then having them rolling roaded and proven to have less power than VW claim, this in-turn has allowed them to return their 170's back to VW for refunds, also effects audi drivers too).

addressing the turbo comment above it's true but not correct. it's the 1.9's that have the Variable vein issues on the turbo's not the 2.0's.
this is an issue where the turbo becomes coked up and the veins stick inside the turbo. an actuator moves the veins under hard acceleration to get better performance but what happens is these veins stick and jam OR the actuator sticks and doesn't return them back to normal position.

ski's comment is bang on the money, swap the water pump with the cam change but this only applies to PD engines pre 03.

as for steveh i have only ever heard of the 6th gear issue once and that was fixed by replacing the pin £3.19 cost from VW never once have i heard of it dropping into the box (and i would be surprised to as the pin screws in from the outer of the casing into the selector shaft which is 8" above the input shaft and still inside the gearbox housing, only way it would drop in i could see is due to it snapping ans someone not being careful and dropping the snapped part into the gearbox) i have seen a worn pin that caused selection issues.

there are a lot of false truths about VW engines (as there are with others too)
Depending on how new you want the car i would suggest looking for a 130PD in a golf or bora, they have a 6 speed box, return 48-50mpg easy (if you do a few motorway miles and drive nice you can get 52+) i would look out for the sticking veins issue (this is normally more common on "softly" driven cars as giving it a regular boot will keep the actuator working unlike ones where owners have pootled about and never used the VVT function. hope this helps a little (if you need this info mail me i can hopefully help).

Questions best addressed on http://www.tdciforum.co.uk probably.

Yup, the 130PD is the best engine of the bunch, I have one in my Ibiza FR TDi.

I can quite easily get 65mpg by driving economically on A roads, 50 ish usually & 45 if I boot it a bit.

Good to see you've been converted from the Puma & Focus(?) Fozzy 😉

Andy B.

130PD is old hat tho. You won't get a PD130 in a jetta only bora/mk4 golf as stated.

the 140bhp engine runs more boost to make the power, in order for it to not pre-detonate and melt a piston, you need to add more fuel to the mixture to keep the cylinder temps at bay

2.0 gt tdi golf

58mpg from GT home being frugal, 48mpg if i boot it and stay within the speed limit (taken as an average speed).

Only runs more boost if you demand it though, just keep your right foot off the pedal 😀

old hat!! LOL says who? you!?

common rail systems are no where near PD/ECI pressures. only now are they achieving 2000 bar pressures, 8 year old PD systems still get 2200 and modern ones are over 3000 bar.

only reason why common rail is as popular as it is, is because it's cheaper than PD systems. they are still no where near the pressures and burn efficiency of PD injectors!
The 140 does not run more boost either, in fact it runs less, it's a completely different pump/injector/fuelling system and how turbo boost relates to pre-detonation or melting a piston god only knows!

LOL armchair critics.

good call on http://www.tdciforum.co.uk/
also visit http://uk-mkivs.net/
and any of the other golf/bora forums.

Difficult coffeeking. I`ve got a 140 Touran and love it 👿

I am not the most "careful" driver when it comes to the right foot but can easily get 48/50 on a run(Carlisle-Edin last week). Rarely drops below 40 even around town if using light throttle.

Only issue I have is a flat spot @2500rpm when feathering/lifting/accelerating throttle in any gear, you know that momentary lift/press moment.
Any thoughts fozzy ❓ Ta.

old hat!! LOL says who? you!?

common rail systems are no where near PD/ECI pressures. only now are they achieving 2000 bar pressures, 8 year old PD systems still get 2200 and modern ones are over 3000 bar.

only reason why common rail is as popular as it is, is because it's cheaper than PD systems. they are still no where near the pressures and burn efficiency of PD injectors!
The 140 does not run more boost either, in fact it runs less, it's a completely different pump/injector/fuelling system and how turbo boost relates to pre-detonation or melting a piston god only knows!

LOL armchair critics.

You seam to have vastly jumped what i was saying RE: Old hat. I didn't mean in the sense that the system is out dated, i was saying you won't get PD in a jetta, they're all common rail. I agree that PD is a far superior system to C/R.

I was merely stating that to stop melting a piston with higher boost levels you must add more fuel RE: the question why a 140bhp car uses more fuel than a 105bhp car. Apologies if my posts were not clear

Had Mk V Golf 2.0 TDi and would get 54 MPG with ease and that's me driving, booted only went down to 52 mpg. Now have the MK VI which is a truly amazing engine now average 59mpg without trying and current record when taking it steady is 74mpg long runs is easily 64mpg. None of the cars I've had ever reached more than 11k miles before I moved them on so hadn't even loosened up.

48-50mpg

I would really like to do better than that. When you lot say 'being frugal' do you mean 50mph everywhere or what? The driving would mostly be the M4 @ 70mph.

The MkVI has a CR engine doesn't it, in a 1.6? Too new for me to afford tho.

I was merely stating that to stop melting a piston with higher boost levels you must add more fuel RE: the question why a 140bhp car uses more fuel than a 105bhp car

Doesn't that only apply when you've got your foot to the boards? At a constant 70mph, surely it should be the same? Although I guess, after having messed with the timing on my ancient wagon, more intelligent timing controls could help, or multi-stage injection.

Doesn't the PD version have 4 fuel pumps…?
Dont know where I read it, HonestJohn I think.

To me the 2.0l 16v drives almost like a petrol without the traditional tdi dollop of torque.

This is my PD130, I've done quite a bit since this printout, now 245bhp 380lb/ft @ 2400rpm.

schrickvr6 that must get through some rubber!

I take it that its not running on a standard clutch 😉

schrickvr6 – what have you had done to that? my PD130 is at 195bhp and 300ft/lb at the moment

59.6hp losses?

I saw a PD130 kicking out 205bhp on the dyno at Awesome in Irlam.

The smoke generated was overwhelming.

PD130's are the best, i have the pd150 ARL and prefer my girlfriends pd130 for bottom end pull over my 150.

@ takisawa2
where the cam is over the head of the engine, the injectors sit, these injectors have a pump attached to them that runs off the cams. each turn of the cam to open and close the valves also plushes the plunger on the pump attached to the injector.
so in effect it does have 4 pumps, one per injector.

Trekster, I know that feeling, I have a 140bhp passat est with the dsg box & find pulling out of junctions can be a bit hairy as you hit the flat spot & the DSG box is trying to work out what to do .. a bit unnerving when there is a car coming towards you & you arent really going anywhere.

I just got a Skoda Fabia VRS the 1.9 PD 130 i love it. get about 55 mpg on the run to Cornwall and over 45 around town. got my dad to call RAC tech support (he's a RAC Patrol) and they said they get the only thing is some filter system gets coked up a bit but that can be sorted by driving on high revs.

Gee-Jay get it tuned, sounds daft but you can get the DSG reprogrammed, we have a member that has had his 140 bhp upgraded to 175-180 and his DSG firmware (software) upgraded and it's amazing, lightening fast changed no hesitation..

@Skankin_giant thats the sticking veins issue that most PD engines have. mare sure you spray a little WD40 on the actuator arm linkages and boot it occasionally (once a month say) just to activate the wastegate linkages and actuate the veins.. all will be sweet.
also try some millers diesel sport 4 if you want a quieter car and more MPG. £12 from halfords or less on ebay for 10 treatments! good value considering most others are one shot jobs.

fozzybear, cheers, I have been considering it … next time there are spare funds it will happen 🙂

Ah Cool Cheers Fozzybear, will do i just came from a Saxo VTR so used to pushing the loud pedal, lol tho i didnt have 1 that drove through halfords it was standard. got out of engine tunning when i got rid of the mini and my old imp. though do like the look of the superchips for these.

interesting read … my gt tdi 130 pd (damn thats a tag and a half)
is still going strong after 150k from new with no problems, failures
or issues at all. Almost perfect diesel – turn the key and drive 🙂

And according to the dash computer high 60's mpg on the commute up and
down the M4 !!!

therevokid – Member

interesting read … my gt tdi 130 pd (damn thats a tag and a half)
is still going strong after 150k from new with no problems, failures
or issues at all. Almost perfect diesel – turn the key and drive

And according to the dash computer high 60's mpg on the commute up and
down the M4 !!!

Covered 60k in mine so far and on the dash computer it has avaraged 45mpg over everything and will do 55 mpg on long runs.

Found out recently there is a switch at the top of the fuel tank which if you push when filling up, will give you roughly another 4 litres in the tank (golf).

It lets you fill the expansion tank, not recommended as if your fuel expands it will spew it out everywhere, but if you are planning a long trip 😉

well i never … dashs out to take a look …. so there is !!!

Skankin_giant
two recommendations
R tech tuning and chippedUK
used both, excellent results from both and good guys at both ends, we got a deal recently for a full RR and tune for under £300 which is a good price really considering a RR costs £70.

Ski – Yeah I get through my share of tyres lol.

Amazingly the original clutch is still going strong, have done 20k miles with not even a whiff of slippage, when it eventually decides to die will probably go for a Spec or a Sachs VR6 with the single mass flywheel. I had a Helix on my old VR6 and not impressed, it only lasted 3k miles but then it is a motorsport clutch and not designed to last forever.

It doesn't take much to get alot out of the PD130, I've done –

VNT 17/20 hybrid
Forge FMIC with all original pipework replaced/rerouted
3" turbo back exhaust with no silencers, just one resonator
EGR deleted
Green panel filter and Ibiza Cupra TDI snorkel
Custom remap
And fed on a diet of dino juice, bio, millers, water and methanol.

I'm still not entirely sure what is the quickest way to drive it, if you rev it the power is good but then you miss the sledgehammer of torque in the next gear, it actually sounds good for a weasel too, a few people properly into cars have asked wtf is in that, and were very suprised when told it's a derv.

Smoke is not terrible, the guy who I bought the turbo off though had much worse smoke and less power, although I think the back end of a Fabia is some kind of particulate magnet as my car is normally two tone red with a black back end.

Also the more it's been modified the better the economy has got, you can just surf on the top of the huge 'torque wave'.

Cool, wont be lookin for 6 months or so want to kep my warrent for the mo.

@schrickvr6

my FR does smoke reasonable abount but the torque is amazing, 30mph, 6th gear, foot of the gas and the thing accellerates.

I have found that if you change gear at just over 3500rpm instead of holding out to 4000 you get the torque in the next gear aswell.

"Also the more it's been modified the better the economy has got"

Depending on the method of measuring, the consumption read-out on the dash may now be inaccurate. Increasing fuel pressure or pulse width may result in more fuel injected than the trip computer's algorithm will be calculating.

PD's do not have fuel pressure increased much normally 1 bar (when you consider the lift pump is currently supplying 5.5-6 bar already it's not a huge increase.

the increased power is down to multistage injection programming for the diesel delivery and better burn timings on ignition and compression strokes. agree the dash is out (mine over reads by 2 mpg) but most modern diesels are designed to run at their most efficient at higher levels than they come to you the customer.
for example a 136bhp focus diesel runs best at a setting where you get about 160-165 bhp out the engine BUT this pushes it up over the 160 limit on CO2 so means a higher Tax bracket. Ford choose to lower the efficency to get the CO2 output lower to put it in a cheaper bracket making it more attractive to you.
sadly this detuned nature means a less efficient car. the higher the pressure of the fuel supplied to an injector the MORE efficient the atomisation and burn is of that fuel. so lower pressure, means poorer atomisation of diesel fuel so poorer / dirtier burn.