Leon hits 70mph, loses power and won't go above that speed!

[cdy]

Hi all, I'm having trouble with '55 plated 1.9 Leon at the moment. It hits a certain speed, typically between 60mph and 70mph then loses all acceleration power, meaning I can drive no faster than the speed it peaked at.

I changed the oil and fuel and air filters and used some 'injector cleaner' but none of that worked, so I took it down to a local garage for a diagnostic. They found two faults: 1/ coolant temperature sensor, 2/ brake pad sensor. I had both replaced, however neither repair has resolved the problem. Had it back down the garage and no faults on diagnostic ... Bloody mechanics these days, so dependent on diagnostic machines!!

The fault is intermittent; there are occasion when I can go well above 70mph. However, more often than not I have the problem described above.

Engine management light is on too, but this has been on for ages. (Took it to Seat garage a couple of yrs back and they told me there were no faults and basically to just live with the fact that management lights sometimes come on!)

Any help appreciated.

 

[Guizado]

Does this happen only at 60/70 mph??
How many RPMs is it going when that happens?
Does it get back the power if you turn the car off and on again?

I smell Sticky vanes or a Vacuum leak, but its weird that it doesn't throw a fault code.

Try moving the actuator on the turbo several times and give it another go, hopefully if it doesnt do it again for a while it means your turbo needs some Mr Muscle or Innotec.

 

[benj1989]

Isn't that the speed limit. Surely you woulnt ever over that lol

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[Guizado]

Isn't that the speed limit. Surely you woulnt ever over that lol

Sent from my LG-P920 using Tapatalk 2

You get 10% leeway so thats 77

 

[cdy]

You get 10% leeway so thats 77

10% plus 2mph I believe!

 

[cdy]

Does this happen only at 60/70 mph??
How many RPMs is it going when that happens?
Does it get back the power if you turn the car off and on again?

I smell Sticky vanes or a Vacuum leak, but its weird that it doesn't throw a fault code.

Try moving the actuator on the turbo several times and give it another go, hopefully if it doesnt do it again for a while it means your turbo needs some Mr Muscle or Innotec.

Once I've made sense of that I'll follow your instructions, mate!

 

[aymen_a22]

Take it for a spin and go full throttle in 3rd gear, when you get to around 3000RPM you will probably go into limp mode (which will limit boost to 15% I believe) if you have sticky vanes.

Common problem, easily fixed.

 

[traumapat]

had a similar fault on our passat tdi. turned out to wiring injector loom.
This bought up a code eventually. If theyre saying ignore the fault lights as "they just come on" id try a better garage.

 

[cdy]

had a similar fault on our passat tdi. turned out to wiring injector loom.
This bought up a code eventually. If theyre saying ignore the fault lights as "they just come on" id try a better garage.

It was the Seat garage on the North Circular that said that to me!
Wiring in the injector loom is the sort of thing I suspect it to be.

 

[cdy]

Take it for a spin and go full throttle in 3rd gear, when you get to around 3000RPM you will probably go into limp mode (which will limit boost to 15% I believe) if you have sticky vanes.

Common problem, easily fixed.

Not sure how going into limp mode will help??

 

[traumapat]

It was the Seat garage on the North Circular that said that to me!
Wiring in the injector loom is the sort of thing I suspect it to be.

independent vag garage should be more helpful than dealers. I dont know your area sadly.
if you can get the fault codes posted on here it might help

 

[cdy]

independent vag garage should be more helpful than dealers. I dont know your area sadly.
if you can get the fault codes posted on here it might help

Unfortunately don't know the fault codes.

 

[cdy]

Take it for a spin and go full throttle in 3rd gear, when you get to around 3000RPM you will probably go into limp mode (which will limit boost to 15% I believe) if you have sticky vanes.

Common problem, easily fixed.

Really? Has been anything but easy!

 

[cdy]

Take it for a spin and go full throttle in 3rd gear, when you get to around 3000RPM you will probably go into limp mode (which will limit boost to 15% I believe) if you have sticky vanes.

Common problem, easily fixed.

Tried but didn't go into limp mode!