Skoda Superb 2.0TDi 14D 4X4

Driving home last night I had to apply my brakes very sharply and afterwards when i tried to accelerate it was if the accelerator cable was was not fully attached. The car drove home like a non turbo .

There is no warning light. I performed a VCDS Scan which showed no engine related errors.

What should i look at first?

Are there any good guides re common rail limp home mode diagnosis?

 

And any suggestions for garage services to sort it. I live at Shrewsbury but work at West Bromwich.

 

Below is te summary from the VCDS

The fault does not have to be engine related to result in limp-home mode.

 

To experience limp-home mode with no dash warning is extremely unusual.

 

Are you sure it is limp-home mode? Could the brakes be binding, could something have slid behind the accelerator peddle during the episode of hard braking?

 

What is the fault stored under 09-Central Electronics?

Thanks for you reply.

 

Just drove the car again. I know it doesn't use a cable. but it feels like the accelerator cable has slipped so it is not possible to open the throttle fully.

 

Brakes aren't binding and i can't see anything behind the accelerator.

 

I'll drive it the 7 miles into town later and see how it goes.

 

The central electronics issue related to an intermittent numberplate light!

Someone on the yeti forum reported similar. Found a screw behind the throttle pedal and was limiting travel. If you have dsg does it kick down? If it's manual and you have cruise does it accelerate as expected if you use it to adjust speed?

Small stones also cause this, don’t force the pedal or the plastic hinge will snap and you will be knackered.

Usually need the pedal removed to clean out properly. Tool used to press in the clips by the hinge and remove plastic cover near top of pedal to reveal bolt. Careful removing the connector plug, the wires can easily be snapped if you are a bit rough with it. Spring loaded lock tab to release correctly, no tools needed for that, just your thumb.

Smallholdertoo, you say you had to brake very sharply. I seem to remember that some owners have had a similar problem which strangely turned out to be a faulty brake light switch. Do your brake lights work?

I had this twice with my 02 passat SE 130TDI DSG and 96 A4 90 TDI auto.

 

one cat replaced under warranty at about 2 years (Audi) and one I had to pay for at about 8 years (Passat)

 

If you braked hard and then the problem came on it can be the cat guts have collapsed and it's moving about when when you brake. Think of it as a ball in the cat, when you brake it rolls forward and blocks the exhaust. Apparently driving through a deep puddle when the cat is hot can cause the matrix to shatter, the cat still works so lambda sensor is fine and as (IIRC) that's the only sensor on the exhaust  side of the plumbing nothing gets logged. I was able to bring it on reliably by driving up hills, it freaked the service manager out we went for a test drive so he could see it for himself 🙂

 

There is also a possibility that the turbo high pressure inlet pipe between the turbo and the inlet manifold might have a tiny split, if so, with the bonnet up and in neutral you may hear something - when that pipe split on the Passat it was like a duck quacking under the bonnet when rev'd. Dealer couldn't look for 2 days so I took it to a Lucas service centre where two mechanics spent 4 intriguing hours peering at it from all angles on a rolling road before giving me back my keys and suggesting I took it to the dealer.

 

For anyone interested I went A4 90 BHP auto -> Passat 130 BHP 5spd DSG -> Superb II 170 BHP 6spd DSG and the annual servicing costs dropped by a third with each one 😎

 

HTH regards

 

David

 

Thanks for al your help. I think the issue is accelerator related. I physically pulled up the accelerator as i did so it clicked like a ratchet and has been fine ever since. I think i will get the hoover out as there are a large number of little stones next to the accelerator hinge.

On 14/06/2019 at 18:49, Smallholdertoo said:

Thanks for al your help. I think the issue is accelerator related. I physically pulled up the accelerator as i did so it clicked like a ratchet and has been fine ever since. I think i will get the hoover out as there are a large number of little stones next to the accelerator hinge.

This is common with this type of throttle arrangement, the reason you won’t get any warning lights is the pedal won’t move beyond a certain point, the engine ecu just thinks that’s as much power you want, but you perceive it as limp mode as it won’t go any faster. True limp mode will have the coil light flashing on a diesel and EPC light on a petrol.

If anyone ever experiences an odd resistance on the throttle pedal, limited speed with no flashing lights.......PLEASE DONT FORCE THE PEDAL, the hinge is very thin plastic and will snap. One it snaps you will not even get above idle speed due to the pedal geometry and it pressing on the sensor.

Best option is to initially flick out debris and hoover debris out, but ideally have the pedal removed (tool required for 2x lower clips)  and shaken to get rid of loose debris.

Had to replace 5x pedals in three months for this. 

Top photo shows tool needed to unclip pedal, spike to remove cover for bolt and 10mm socket for the bolt.

The bottom photo shows the witness mark of where the stone was jammed under the pedal and the arrow shows the broken hinge.

The connector plug has a spring loaded release mechanism, no need for tools, just your thumb, please do not pull on the very small wires as they can pull out and snap. 

Edited 16 June, 20197 yr by 3T1704X4

Earlier cars need that red tab pushed inwards and the tab I think is grey.

It looks easy to do but much more difficult when fiddling in the footwell. Be gentle, don’t use a screwdriver (for any of these types of connectors I get annoyed when people muller these connectors using unnecessary tools, then they won’t lock into place) sometimes a gentle push down to release tension on the tang is required to release the plug.

 

 

https://1drv.ms/v/s!Ai0pRE5-oeAIgRTvmWo1PLsLsVl2

Edited 16 June, 20197 yr by 3T51704x4
Trying to upload vid