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Discussion Starter · #1 ·
Having recently bought a Golf 1.9 TDi SE I have a few questions about the car and more sepcifically about diesel engines, would appreciate any comments and advice. My old car was a dated hyaundai accent 1.3 with 115,000 miles on it which needed gunning to keep it going so a new car is some what new to me.

1) The red line on the rev counter is 4,500 rpm. Have you got any advice on if it is necessary to generally keep revs below 3,000? Is this important if the TDi engine is still cold? Is it okay to go up to the red line occasionally? (not that i really ever intend to)

2) Cruise control seems pretty cool but what is the effect on fuel usage? if I set it to 75 on the motorway and just leave it going will it use more or less fuel than me keeping my foot on the gas and adjusting as necessary for climbes and drops?

3) On the radio I cannot figure out the TP (traffic program) it seemed to work for a bit when i was around oxford (bbc oxford) but when i got into berks I did not get 1 traffic report. I have read the manual and tried to figure it out but am not sure if it is working ok or not. Do i need to set something up or should being tuned to an FM channel that does TP be enough?

Thanks will add more questions as I think of them...
 

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Welcome!

I answer to question 1 I suspect in normal driving you will feel no need to go much past 3,000 rpm most of the time but there is certainly nothing wrong with revving up to the red line if you wish, just wait until the engine is at normal operating temps before doing so.

Question 2 - in my opinion (shared by some but not all) cruise control uses a little more fuel than 'manual' accelerating and deccelerating but is very useful for longer trips.

Can't help with Q3 I am afraid.
 

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Discussion Starter · #3 ·
Many thanks for your reply, I too have heard both arguments presented on the cruise control issue. Some people saying it uses more and some that it uses less fuel. I guess in the long run it is not going to make that much of a difference and it certainly is useful for long journeys.
 

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welcome

It is important with all turbo cars to let the oil warm up before thrashing it - its OK to go to the red line as long as you don't spend all your time with the revs that high. You probably don't need to go to 4500 rpm anyway as the power and torque highs will be lower down the rev range.

Seems to be 2 different schoolls of thought for cruise control - personally I don't have it so I can't answer you
 

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Discussion Starter · #7 ·
Really?  In what way is it good for the engine?  I guess it must be designed to operate within those parameters or the red line would be more lik e 3,500 rather than 4,500....
 

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Really? In what way is it good for the engine? I guess it must be designed to operate within those parameters or the red line would be more lik e 3,500 rather than 4,500....
acc. to superchips, the max power of the 1.9TDi arrives at just over 4000 rpm prior to re-map

try looking here for more help http://www.superchips.co.uk/curves/golfmk5tdi105bhp.pdf
 

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I read this on the diesel car forum from what I remember it was regarding gaskets and seals.

It applies to diesels after the period of running in - too much gentle driving means the engine takes longer to bed in and uses more oil and doesn't return good mpg.
 

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It's true, you should give a TDI a good workout every so often using all the revs up through the gears as this clears all the soot out of the system that accumulates when the car has been grannied about or sat in traffic quite a bit at low revs. Helps keep the internals of the engine nice and loose too. Don't worry I don't mean you have to absolutely thrash the car regularly but you do have to actually DRIVE it once in a while.

It's reasonably common for Turbo Diesels to fail emissions on MOTs then go back and sail through on the same test after a quick blast up the dual carriageway up through the gears to maximum revs which clears them out and improves their performance. No this doesn't harm the engines basically and after owning a petrol engine you do have to re-educate yourself to get the best out of a diseasel.

As for the cruise control, Diesels are at their happiest at a steady state cruise.
 

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1) Trying to minimise high revs when an engine is cold is good advice. However, once the engine is warmed up there should be no problems with occasionally entering the red area on the rev counter (just don't run the engine continually, i.e. for minutes at such revs). I agree that an occasional blast does any type of engine good but more particularily a diesel as it can spend so much of its time at relatively low revs.

2) I'm a big fan of cruise control, especially on diesels but agree that on particularly hilly roads, it might lead to slighly increased consumption. On a motorway however I'm sure it'll save you money no matter how severe the gradients are. Just watch it on long steep downhills as it will not apply the brakes.

3) I think the RCD300 unit is not the most sensitive unit with regards to reception. I wonder if your poor TP reception is down to the poorer reception generally offered by the aeriel in the rear windscreen heater element as opposed to the bee-sting aeriel found on the latest 2006 model Mk Vs. If it shows TP on the radio's display, you should be able to receive any TP announcements made by that station, and if listening to a BBC station, any other BBC stations within range.

Stuart
http://www.stuartdalby.co.uk/vwgolfmk5
 

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Discussion Starter · #13 ·
Cheers for all this info guys I will most certainly take it on board and might give her a good old thrashing on the way home today :)

Whats everyone's opinon on using normal supermarket diesel as opposed to the more expensive stuff at ESSO and Shell etc. Is it the same or do you notice a difference paying a bit extra? If so is the difference to Fuel consumption and MPG or more performance related?
 

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Cheers for all this info guys I will most certainly take it on board and might give her a good old thrashing on the way home today :)

Whats everyone's opinon on using normal supermarket diesel as opposed to the more expensive stuff at ESSO and Shell etc. Is it the same or do you notice a difference paying a bit extra? If so is the difference to Fuel consumption and MPG or more performance related?
fuel is discussed at lengh on the diesel car forum

www.dieselcar.com
 

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yes u should on occasion take it to the red line - its good for the engine and exhaust
take it from another 1.9'er over 3000 without super chip is a waste if time, as for the ablove quote who told you that?? 4500 rpm is nothing for the internals its the fuel pump that takes the punishment. I've just had a 2.0fsi for 2 days, what I can say it that a 1.9tdi suspension is from the dark ages (springs and dampers), MY GOD was this car different, like my old focus I was throwing it round corners, jesus so different. I wouldn't entertain one of the lesser models if I chose again.

Cruise control pah makes no difference to economy, i've done 31000 miles in 10 months, CC is invaluable, but its keeps failing, just had it sorted again. I get about 530 miles to a tank I use any old diesel. The economy suffers as does the performance if the service light is on, recently just had it re-set ( the car thinks it should be serviced every month), what a difference, I was getting 450 to a tank and the car was slow after back to 500+ with the torque back, oh that 500+ with superchip driven on the the motorway at cruise SC makes no impact.

Rich
 
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