Engine light on dashboard came on

[seeitright]

My bora is 2.0 auto, year of 2002, made in Germany, almost 90,000km now.

The engine light on dashboard came on in the end of December. The dealer of VW thought the reason is the brake booster pipe was broken. Is that possible? Or it's related to the CAT converter?

Yesterday when I was in highway with speed about 90kph, I heard very big noise from the engine. I slowed down the speed and went to a parking place and opened the bonnet and found that the pipes almost took off from the connection. I connected them again by myself. Now I dare not go to highway, but the engine light is still on.

refer to attached picture from web.

Pls give me some help. I already spent more than $500 for this problem.

[mikeybutch]

You need to get it scanned for faults

[NHN]

Exactly, although it may just be a warning to advise of the system the pipe works inconjunction with isnt running as per norm, so a good jubilee on the pipework & clear the error & take it for a test run, then rescan.

[seeitright]

Thanks a lot for the above reply. The yellow light disappeared automatically this evening. God bless us!

[seeitright]

The light came on again. My God!

[phil miller]

The light came on again. My God!

Have a code read done and go from there mate

[seeitright]

I got the code like "16804. Catalyst system: Bank 1:Efficiency Below Threshold".

So, what does it mean?

Is that related to fuel type? Now I use #95 fuel and I believe the previous owner used #91 fuel.

I changed a new vacuum pipe/brake booster pipe, see the above picture, and I had the error erased last Thursday and today the light came on again.

[phil miller]

I got the code like "16804. Catalyst system: Bank 1:Efficiency Below Threshold".

So, what does it mean?

Is that related to fuel type? Now I use #95 fuel and I believe the previous owner used #91 fuel.

I changed a new vacuum pipe/brake booster pipe, see the above picture, and I had the error erased last Thursday and today the light came on again.

The fault code is saying the cat isnt doing its job properly, ive had this many times and ive seen people replace the CAT and sensors and the problem is still there, it is normally the manifold to downpipe gasket just drawing a little air when you back of the throttle, for a split second it draws fresh air in and this gives the sensor a different reading to what it should be, very common on mk4 golf GTIs, if you know of a garage with a smoke machine get them to test your exhaust system, this will fill the exhaust with smoke and you should see the smoke pouring out from the manifold to downpipe gasket, replace the gasket, clear the code and that will sort it mate

[NHN]

http://wiki.ross-tech.com/wiki/index...4/P0420/001056

[seeitright]

The fault code is saying the cat isnt doing its job properly, ive had this many times and ive seen people replace the CAT and sensors and the problem is still there, it is normally the manifold to downpipe gasket just drawing a little air when you back of the throttle, for a split second it draws fresh air in and this gives the sensor a different reading to what it should be, very common on mk4 golf GTIs, if you know of a garage with a smoke machine get them to test your exhaust system, this will fill the exhaust with smoke and you should see the smoke pouring out from the manifold to downpipe gasket, replace the gasket, clear the code and that will sort it mate

Thanks a million for your great help.

Would you mind to show me the position or location of the manifold to downpipe gasket using a picture or diagram?

Is that very expensive to perform smoke machine test and change the gasket? How many gaskets should I order?