After installing the pipewrex downpipe, CAI and Bluefin stage 2. All was going well until today. I was just cruising along in 4th at about 3000 rpm and the CEL came on and stayed on.

When i got home i cleared the light by disconnecting the battery and went for a drive.....nothing...no light even when driving hard.

Random or what?

whats cel out of interest

gotcha, lol, i knew it would be something obvious.

That light is in the manual as exhaust control system. I had it flash up on my dash 3 days ago,

I keep saying it and I'll happily say it again - If you boys want to run highly modified cars your most important addition to your toolbox is VCDS.

There is little point in posting something here like my CEL came on, it could be a number of things and any replies or suggestions are purely guesswork.

Your most important addition to your toolbox is VCDS.

It could be a number of things and any replies or suggestions are purely guesswork.

Got to agree with you Stu! It mean that a fault has been logged, what that fault is, is another issue!

My CEL came on a few months ago after a spirited drive in North Yorkshire. In fact it came on moments after hitting a rather large pot hole !

Car drove fine but a scan with VCDS showed that as I have the auto locks enable, the rear offside door had become unlocked, & the time code coincided with the pot hole incident! Sure enough it was the rear offside wheel which had hit the pot hole the hardest

Resetting the door locks & clearing the fault code was all that was needed!

So mate bearing in mind your problem with the diverter valve, i'd get it scanned as soon as possible to make sure that all is alright! A quick search should show you if there are any VCDS owners in your area who might be able to help.

how much is this vcds kit and where would you buy it from. and is it just software for a laptopand a connector lead

You actually purchase the license in the cable. The software is free but the cable isn't.

Ross-Tech: Home will help although it is possible to buy from UK sources. You might even pick it up in Germany cheaper as well.

Alternatively you could look at the list of vag-com (VCDS) owners.Diagnostics & VAG-COM General Motoring Discussions - Diagnostics & VAG-COM at BRISKODA.net - BRISKODA - The Skoda Forums

Haha! I deserved that but I am not some kid new to modifying cars stu a bit old skool maybe (its been a good 10 years since I last did any serious tuning).

I actually have Vagcom but it’s the old type, had it for my Audi A3 when i started tuning that. The reason I posted this was not so much that the CEL had come on (I know I'll need to scan for that) more that it hasn’t returned since.....weird occurrence as i wasnt doing anything out of the blue at the time.

I wasn't suggesting you were an amature

However I stand by my original comment and I'll give you an example that has affected Hedge and one or two others I know of -

CEL comes on and eventually goes off, do a scan and you find something like intake manifold runner sensor out of range lower limit exceeded (or words to that effect) and basic settings adaptation not complete (and again, or words to that effect).

Now this will require some new replacement parts to fix a known problem which if you are under warranty is ideal however leave it undetected until out of warranty and be prepared to put a kidney on eBay.

Ahh here we go, found a scan on my PC -

2 Faults Found:

012599 - Intake Manifold Runner Control: Basic Setting not Completed

P3137 - 001 - Upper Limit Exceeded - Intermittent

Freeze Frame:

Fault Status: 00100001

Fault Priority: 0

Fault Frequency: 3

Mileage: 35519 km

Time Indication: 0

Freeze Frame:

RPM: 0 /min

Load: 54.9 %

Speed: 0.0 km/h

Temperature: 70.0°C

Temperature: 52.0°C

Absolute Pres.: 1020.0 mbar

Voltage: 8.763 V

001602 - Sensor Reference Voltage A: Circuit: Low

P0642 - 002 - Lower Limit Exceeded - Intermittent

Freeze Frame:

Fault Status: 00100010

Fault Priority: 0

Fault Frequency: 3

Mileage: 35519 km

Time Indication: 0

Freeze Frame:

RPM: 0 /min

Load: 54.9 %

Speed: 0.0 km/h

Temperature: 70.0°C

Temperature: 52.0°C

Absolute Pres.: 1020.0 mbar

Voltage: 9.779 V

Readiness: 0000 0000

-------------------------------------------------------------------------------

Now you'll see that this happened at 54% load, 1020mbar which would indicate off boost (not wishing to teach you to suck eggs but 1020mbar would have been roughly atmospheric at the time) so not exactly hoofing it around. (It also says 0 km/h but these aren't always accurate for that field)

Its certainly a concern, thanks Stu.

I've got one of the Seatcupra.net guys bringing his VCDS to the North East Rolling road day on the 21st so will hopefully get to the bottom of it.

I presumed that now that I've flashed the ECU 4-5 times and fitted some non standard parts, I would have buggered my warranty :(

Lets see what it says. Its the first time I've had a CEL on this car in nearly 2 years of ownership.

You don't void warranty in it's totallity only parts that have been directly affected by the mods - That's up the the garage, yourself and maybe Skoda to thrash out.

Got the BF handset back today with the new firmware for reading DTCs....I tell you, Bluefin is a bargain now you can also read DTC and do data logging

P0139 : Oxy Sens Circ Slow Response (bank1,sens2)

P1602 : Power Supply (B+) Terminal 30 Low Voltage

I'm pretty sure i know what this is, the second O2 sensor mounting on the pipewerx DP is blank at the very end so that the sensor doesnt pick up issues when over fueling to cool the turbo, i guess my ECU doesnt like it. Should be easy enough to drill the blank end out so that the sensor is able to create some gas signals.

The P1602 is probably becasue I disconected the battery when i worked on the car.

Fingers crossed this is the problem!

I just wonder why the O2 sensor would cause the car to go into limp mode?

Thanks to all that helped!

Edited 19 March, 200917 yr by Hofmiester
typo