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Discussion Starter #1
Have a 2002 GTTDI 130
Goes like a rocket, no turbo lag etc.

Fuel consumption is not good, 42ish at best, my Passat Est 110 can do 60mpg

The braking is severe, you cannot slow at a junction gracefully, the brakes only need the lightest of touches to come on. Have stripped and cleaned the brakes,but no change.

Ref the fueling/performance have checked the turbo for movement of actuator,seems OK, changed a suspect rubber seal on the main air pipe after the turbo, this to try and prevent any overboost/fueling as maf would see all air going to turbo, and turbo could be overboosting due to air leak on downstream side, then the ecu could over fuel, hence my rocket acceleration/performance and poor economy (my theory)

Is there a common thread between brakes, vacuum, n75 valve etc that is causing these probs? Have driven an Audi 130 and this car will eat it, but I'm not looking for performance, just a normal 130 with good economy and sensible brakes.

The car definately hasn't had the ecu chipped as ECU map checked by garage, and there are no visible add on devices plugged into maf or water temp sensors. Car only went into limp mode once I think, as I wasn't the driver, due to overboost which was on the memory (detected and removed by garage), when restarted was OK and still is.

Car has been serviced, doesn,t blow any smoke out, drives very well in all other respects. Have just put come redex into fuel, but on this last motorway journey at 80ish the consumption was still 42 mpg

Have read through all the threads on Turbo, Actuators, n75 etc and all seem to be associated with loss of performance, I,ve got too much! and too much braking efficiency....whats the link?
 

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My guess about the brakes: the brake pad is too aggressive. When you tap the brakes, it grips too much. Aggressive brake pads don't make you stop shorter but they do change the braking feel.

It's possible that the rear parking brake needs adjustment. Maybe it is slightly rubbing and this causes your more than normal braking and low mileage.

Jack up the rear of the car and see if it's rubbing. A little touch between the pad and rotor is normal but resistance is not.

The other problems could be a boost or vaccum leak that you haven't found. Try this: http://www.myturbodiesel.com/1000q_how_to/multi/boostleaks.htm and then inspect all the vacuum lines. It's possible that there is a defect that you can't see somewhere.

And if this is a pumpe duse or automatic transmission, those will lower fuel economy compared to other units. I'm not sure if that year Euro golf is pumpe duse.
 

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Maybe air in the brake fluid lines? You need to bleed the ABS pump and the lines in a specific order to make sure all the air gets out. Maybe the worse fuel economy is due to using a more powerful car like a rocket? The more you use the power the lower fuel economy will be.

If your theory about the turbo is correct than you need at least a boost gauge or vag com to take some logs and check the values.
 

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Thanks for replies,will be having another look for leaks at weekend.

When I checked the brakes previously, the handbrake was fine. With the handbrake off the car will easily roll, all discs are new.
Do you know if the front calipers should have spacers or anti squeal shims fitted, mine doesn't and this may have some influence on the "savage braking" effect? Spacers may give a bit of give/travel before piston is hard on disc (theory)

Drove the car again today on motorway journey, and it is very difficult to drive at a 60/70 mph average, the accelerator is a bit like the brake, very sensitive, even the slightest of movements and the car is off and wanting to cruise at 80/90.
Just managed 44 mpg average; watching the average and actual mpg computers as I drove trying to figure out what may be wrong. The actual computer was following the accelerator pedal movement/performance exactly.

Could a faulty temperature temperature sensor be kidding the ECU I'm running cool? what should the resistance be across terminals at ambient and hot conditions?

The car is a 6 speed manual.
 

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A faulty temp sensor is a common issue, it shouldn't cause the accelerator to be touchy, maybe the pedal is bad or a wire is crossed from the pedal cluster? Garage didn't find any other faults?
 

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Discussion Starter #6
Driving today and the car went into limp mode whilst at speed on motorway, stopped and turned the car off, then restarted and it was back to its manic condition. Rang the garage today and they had checked the Water temp sender at its last visit, so have booked it back in for a thorough going over.
Also checked with VW on whether the car had pad shims, it doesn't ,so a new set of pads will be going in just in case previous owner had fitted dodgy or soft pads.
Will report back findings.
 

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if you have lack of power , car feels like draging ,brakes stuck,and bad mpg,


use some fuel add.( sea foam....). run the car on hwy atleast 2 tanks .it may clean the injectors.

i had to change the injectors.(1200 dol.) you can have tem cleaned and or

change the tips . good luck
 

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Garage had the car for two weeks, tested everything on the vagcom, in the workshop and out on the road. Turbo actuator and vanes all OK, MAF and engine temp sender OK. Drew a complete blank, all components within spec and nothing that they could suggest changing, no fault codes coming up.
To their credit they didn't charge a bean as they couldn't determine a fault, very unusual in this day and age but we still have some honest garages here in UK.
I'm going to change the pads, just to tackle/isolate this fault, it may have green stuff pads fitted.
 

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Good idea, fix 1 thing at a time. When they check the MAF, make sure to really check it since a quick inspection won't reveal any fault. The normal mode of failure is a slow failure and low air reading, not a sudden failure. If they deal with VWs they probably know this.
 

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Here is another thought on the mileage - it's all about the GT versus a lower powered car. If others who have the same model are getting plus/minus 5-10 mpg then it should be right on.

Have a 2002 GTTDI 130
Goes like a rocket, no turbo lag etc.
 

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Discussion Starter #11
Have just changed the front pads, but talking to another guy at the local motor factors who has a 130, he tells me his brakes are just as sensitive.
Also the brakes on my 130 are brakes from the 150 model, probably VW fitted 150 brakes at the factory, they all look original and don't appear uprated by previous owners.
I do have another question, since the new pads don't have a wear sensor ( one of the old pads on N/S had one), the orange warning light is illuminated on the panel.
Is there a way of removing this warning?
I haven't cut any wires back, just taped up the plug.
At the moment the brake sensor will be open circuit, not sure if linking the wires will clear the fault or does it need a resistor etc.
Any ideas?
Thanks
 

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Thanks Desolit, I'm just out to check circuitry with my multimeter and a loop of wire. Think it's a quick fix, let you know.
 

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Checked the old pad with sensor, normal is continuity, and therefore just needs a wire linking at the pad end to put the light out. Removed the plug from the old pads and cut the wires, twisted and soldered the ends before poking them back into the rubber shroud. Plugged the assy back into socket at wheel and job done, no light when driving.
You could have cut the plug off at the wheel and linked the wires, but this way you can always revert back to pads with sensors.
Took the car out for a spin and the brakes are definately not as agressive, still powerful when you want them, but not the savage application as you touch the pedal.
Lets hope thats the brakes sorted and they don't revert to previous as they bed in.
No doubt the wife will tell me.
Will now concentrate on the poor fuel consumpion issue and report back if successful.
 
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