Seat Alhambra 1.9Tdi 115bhp-Limp Mode | Technical matters | Back Room Forum

Mon 7 May 2007 15:36

Seat Alhambra 1.9Tdi 115bhp-Limp Mode - bertie

Hello, l would be very grateful for any help, opinion, information or experience of a problem with my vehicle.

l've been looking through past threads & it doesn't seem to be a unique problem, though a difficult diagnostic one.

The vehicle in question is a Seat Alhambra 1.9Tdi 115bh with an AUY engine & has covered 130,000 miles, with a full service history.

Most of the time it's a pleasure to drive, very reliable & economical for the size of vehicle. However, under conditions such as accelerating to about 3,500 revs, when overtaking for example, you can gaurantee that the turbo will be shut down & the engine will be put in limp mode. Stopping the car switching off the engine & restarting will correct the problem. Much more infrequently, the engine has been found to be in limp mode straight from start up where the engine has not reved hard however, again the process of turning the ignition off & restarting resets & the turbo is normal.

l have had a diagnostic check carried out with the Volkswagon/Audi sofware, with no faults/errors being identified. There is no smoke produced & as l say, otherwise it runs fine.

Reading the threads, other people with the same problem have questioned the turbo itself, the Mass air meter (which has recently been changed) the coolant temperature sensor & the ECU. However, a common trait with this seems to be a split, loose or collapsed rubber pipe related to the turbo/valve.

l would be gratfull for any info' on exactly which pipe may be at fault, or any other suggestions.

Reply | Report as offensive | Link

Mon 7 May 2007 16:31

Limp Mode - Seat Alhambra 1.9Tdi - 115bh - Screwloose

bertie

If it's going into limp, then there is at least one code in there; probably 17965 - overboost.

Find someone with the correct equipment and see if there are any other codes that might narrow it down from things like the N75 turbo control valve, those little rubber hoses, the MAP [thrust] sensor or the turbo sticking.

DON'T throw money at it; a grand+ spent and still no fix is quite common for this one. Oh - and it's not the MAF or the coolant sensor if it's dropping to limp.

Reply | Report as offensive | Link

Tue 8 May 2007 13:09

Limp Mode - Seat Alhambra 1.9Tdi - 115bh - bertie

Screwloose,

thanks very much for the response.

l get the picture, from previous threads, that other owners of vehicles with this problem have had terrible trouble & expence identifying the cause; it's something l want to avoid!

As l said, l've had the independant VAG garage take a look at it, with no codes recorded. l have also taken it to a recommended garage in Birmingham, who claimed to specialise in diagnostics, with again nothing.

When you say someone with the correct equipment, are you referring to a main dealer?

Reply | Report as offensive | Link

Tue 8 May 2007 16:02

Limp Mode - Seat Alhambra 1.9Tdi - 115bh - Screwloose

bertie

I've never seen a case of a VAG TDi where it drops into limp home [the key-off-on instant reset is the test] and doesn't store a code.

If it were just a loss of power and no code, then the MAF would be high on my list of specific tests; but defaulting to limp is a serious step for the ECU to take and it will record it's reason for doing it and also store a "snapshot" of the relevant live data at the moment it did it.

Check the operation of the brake lights. The pedal position sensor/switch is the commonest fault on these; it doesn't fit the symptom, but it is a free check.

Any scantool [or VAG-Com] should be able to access any stored codes - unless there's a fault with the self-diagnosis system in the ECU as well. In that case; it will be necessary to provoke the fault while a recording scantool is actually connected.

What exact year is this [obviously it's 2000-on] and does it have traction control?

Reply | Report as offensive | Link

Tue 8 May 2007 16:17

Limp Mode - Seat Alhambra 1.9Tdi - 115bh - injection doc

yep I agree with screwloose, thourghly check brake lights & make sure correct bulbs are fitted in there correct position! you need to check that no filiments have crossed and that if your fittings have offset pins that offset pin type bulbs are fitted! check & check again Its free.
On the odd occasion have had to remove the complete inlet manifold and have internally cleaned at an engine cleaners bath to remove all the internall gunge to stop this fault occuring & there are two valves mounted on the bulhead that have given simular faults1 check that you dont have a kink in the end of the exhaust! & I have had these where the cam lobes have worn badly stopping the engine exhausting properly, theres proberbly a thread on this problem somewhere.
Regards

Reply | Report as offensive | Link

Tue 8 May 2007 21:28

Limp Mode - Seat Alhambra 1.9Tdi - 115bh - bertie

Screwloose/Injection Doc,

firstly, thanks very much for the response/info.

It's a 2001 Y registered vehicle, without traction control.

l'd heard that the brake lights may have something to do with this problem, worth checking.

Reply | Report as offensive | Link

Mon 11 Jun 2007 12:18

Seat Alhambra TDi - bertie

Hello,

you may recall, about a month ago, l asked for the forums opinion regarding my vehicle going into limp mode, when under certain conditions.

Through good repeated "snapshot"diagnostics, the problem was identified as a turbo boost control valve.

This has now been replaced to good effect.

Thanks to all who responded.

{Moved to original thread - DD}

Reply | Report as offensive | Link

Sun 26 Sep 2010 17:56

Seat Alhambra TDi - Iqbal Sheryar

Hi i have a Seat Alahambra 1.9TDI which has been suffering the dreaded limp mode on start up it's fine when you drive it it's fine turbo kicks in and it's a pleasure to drive until i reach 50Mph or when the car is nice and warm the limp mode kicks and if i switch the ignition off anf back on again it's back to normal until i reach 50Mph again.,I have it on the VAGCOM which picked up 1 fault 17965 Charge Pressure Control Positive Deviation.

Things I have Changed

Both N75 valves

MAF sensor

Cleaned Out EGR valve which was full of crap.

Cleaned out the Turbo with Innotec tried moving Acutator Rod but it's stiff and can not move by hand,

New Fuel Filter

New MAP Sensor

Checked all hoses no leaks seen,

engine flush and full service done.

Anyone think off anything else i can check or change or possibly a clue of what it could be.I have been on numerous forums where people have or are suffering similar problems but no one has a logical reason behind it,Mechanics are baffled Seat who built the thing are Baffled and so am i.

Any help would be appreciated.

Thanks

Still the problems remains.

Reply | Report as offensive | Link

Sun 26 Sep 2010 20:14

Seat Alhambra 1.9Tdi 115bhp-Limp Mode - Railroad.

This is a very common problem on VAG vehicles with VNT turbos. The turbo vanes are variable and controlled by the ECU. The problem occurs when the vane ring becomes stuck and will not move due to the build up of carbon which becomes hard. Typically the engine will perform as normal up to around 3,300rpm. As the vane ring doesn't move the ECU will recognise an overboost situation and drop the engine power to prevent damage occuring. Switching off the ignition and restarting will reset it and you can drive on as normal until you reach this engine speed again. Usually you will not need a new turbo but many garages will tell you otherwise and try to sell you one. Click on the link below for full details on how to fix it, but beware, it isn't a job for the faint hearted. Once it is fixed make sure you avoid the problem again by not driving on short journeys all the time and give the engine a bit of stick once in a while to keep the vane ring free.

http://forums.tdiclub.com/showthread.php?t=140910

Reply | Report as offensive | Link

Ask Honest John

Sell Your Car

Real MPG

Fuel Calculator