Cupra feels sluggish

Firestar_3x · 22 Apr 2009 at 12:22

Deffo a good buy, its a key part of 1.8T ownership

Brwmogazos · 22 Apr 2009 at 12:26

DO you have a boost gauge?

Your boost pressure is doing up and downs?

surging?

could be N75 too...

When you buy the vag com cable, check your g/s block 002 or 003

usually when the maf goes.....TCS also lids along with the CEL

Virdi · 22 Apr 2009 at 13:29

Ok - here's another guide to check the MAF:

To see if the MAF readings are out by using VAG COM With the engine running and up to temperature, Air Con OFF. Go in to engine, then go in to Meas Block you will have 3 blocks to use you’ll only need 1. Use address 002 and click GO. You will now see the rev speed (780-820 RPM @ Idle) and a MAF readings in G/S (Grams Per Second). Ok at idle the reading should be around 2.7-2.9 G/S now try and hold the revs around 3k at this point he G/S should be 9-10 G/S. If you see a different figure at these points the MAF is on its way out and is causing a Air fuel ratio issue which is effecting you power.

Eriedor · 22 Apr 2009 at 13:48

Is the VAG cable the same for 1M and 1P variant leons?

Buying from original supplier is quite expensive!

Skiddley · 22 Apr 2009 at 14:02

Don't these have re-circ valves, so you wouldn't expect to hear the 'tshh'?

I did blow a pipe completely off an 05 Cupra R once, immediate engine management light though - and seriously degraded performance - similar to a coil pack failure.

paradigm · 22 Apr 2009 at 14:03

They do have re-circ valves, but you can hear a "tssh" if you listen closely (or fit a forge 007p backwards).

Tombles · 22 Apr 2009 at 14:19

As Para said there is a "tshh" noise but you do have to listen out for it, only really noticeable when the windows are open otherwise you wouldnt really hear it.

Virdi - Thanks for that, will try and have a look after work.

Brwmogazos · 22 Apr 2009 at 14:36

it depends on the sound...this is turbocharger spooling up or surging sound?

paradigm · 22 Apr 2009 at 15:28

Brwmogazos said:
it depends on the sound...this is turbocharger spooling up or surging sound?

Its the diverter valve releasing boost back to the unpressured side of the system.

So essentially a quieter version of the "tssch" you get from a vent to atmos valve on other turbo systems.

Tombles · 22 Apr 2009 at 17:58

So had a quick check and couldn't see any split hoses or leaks.

I also disconnected the MAF sensor and drove around for a bit but didn't notice much difference to when it was plugged in. Not sure exactly what this means.

When i get my VAGCOM cable it should hopefully show something.

paradigm · 22 Apr 2009 at 18:01

If the car is driving similarly with the MAF disconnected then the MAF could have failed or be on its way out.

Although without lighting up the dash, that seems a bit odd.

I'm experiencing power loss issues at the moment, the odd thing being that the one error VAG-COM was showing up hasn't been resolved by replacing the sensor (G31 - Intercooler Boost Pressure Sensor).

So I'm REALLY at a loss!

Tombles · 22 Apr 2009 at 18:10

How should it differ from the MAF being disconnected and connected?

paradigm · 22 Apr 2009 at 18:30

With the MAF disconnected, the car should revert back to "safe" values contained within the ECU. These of course are down on power compared to live data from the MAF, but leave the car in a drivable state.

Dangerous Dave · 22 Apr 2009 at 18:39

paradigm said:
I'm experiencing power loss issues at the moment, the odd thing being that the one error VAG-COM was showing up hasn't been resolved by replacing the sensor (G31 - Intercooler Boost Pressure Sensor).

So I'm REALLY at a loss!

My friend had that and it was a very fine hole in the intercooler.

paradigm · 22 Apr 2009 at 18:42

What was his exact error on the sensor?

I wouldn't have thought that "signal too high" (the error I get) would be caused by a leak, surely that would be "signal too low"?

Virdi · 22 Apr 2009 at 18:48

I think you need to do a boost leak test.

There are testers available like this one: http://www.modshack.info/Pressure.htm

But I have also seen home made one's - You basically cut up a Thermos Flask and stick one of those air valves into it - lol

paradigm · 22 Apr 2009 at 18:50

Might have to give that a go, if I can find a valve that fits on my compressor I'll make my own "tester".

Dangerous Dave · 22 Apr 2009 at 19:04

paradigm said:
What was his exact error on the sensor?

I wouldn't have thought that "signal too high" (the error I get) would be caused by a leak, surely that would be "signal too low"?

TBH I don't know the exact error he got he did replace the sensor though and it made no difference. He replaced a few hoses before finding the small hole in the intercooler.

Have you logged boost requested against actual boost along with the duty cycle of the wastegate ? Should help identify a boost leak.

Tombles · 22 Apr 2009 at 21:00

Been having a look on seatcupra.net and someone else mentioned a big giveaway of a MAF sensor going is a rough idle which i noticed recently in my car. If this is true then seems like i found my problem so just got to get one ordered on pay day!

Virdi · 22 Apr 2009 at 21:46

MAF is very common - So it wouldn't be a surprise.

Try Euro Car Parts or GSF. They even sell 'em on fleaBay, but I wouldn't risk it.

One thing I've always wondered is... Can a MAF not be cleaned?