If The Front Pads Are Changed Does The Ecu Need To Be Linked With The New Sensors!!

[Bodferret]

I changed my front brake pads on my a4 diesel a few weeks back. Its a 2003 1.9 tdi. Anyway all was grand and no raking about in them to wear them in or nothing. About 2 days later i noticed they were getting stiff if i depressed them more than once approaching the traffic lights, to the extent that i couldnt push them in at all and the brake system failed. I never had any sensor lights showing in the dash or nothing. So i carried on.
The next thing that happened was the next morning my car seemed to be taking off with no boost at all. I never put the brakes and the loss of power together or even imagined it. So up came the hood, the fuel filter and air filter got changed, the turbo piping system came off and i cleaned it out. I checked all the hosing and found no cracks, tears or anything. I disconnected the n75 valve and bunged it up. I disconnected the Maf and still the power wasnt there. The turbo comes in around 2500-3000 rpm which i know is too late and had me puzzled. I took it on the motorway and thought maybe it needed a bit of stick, to no avail. It wouldnt go over 65mph and that was on the flat and it seemed the turbo wouldnt engage until i pulled in and switched the engine off.
I was just going to book it in today for diagnostics and the garage manager asked me, if i had disconnected the battery recently. I told him no, but i had changed the front brakes pads (Bosch-sensored) and told him i am having problems with them at the moment. The moral of all this is that he told me that the car could be in LIMP MODE as the brakes are failing.

To all you lads that have a bit of knowledge, could this be true. I phoned a garage today and he said to me that the brakes when changed need to be set again against the ecu. I hope you may have a few answers because i know of a mechanic that can fix all jobs, she is a woman and she said she would do it all for 15p, she goes by the name BO-PEEP.Cheers Bodferret

[Bodferret]

Wow, look at the responses and i thought i was on a forum that had knowledgable people on it... maybe i dont have enough posts to warrant a response...i will hold on a bit longer.....

[bora(ing) nick]

Wow, look at the responses and i thought i was on a forum that had knowledgable people on it... maybe i dont have enough posts to warrant a response...i will hold on a bit longer.....

Welcome to the forum....

I was about to say sarcasm gets you nowhere.... but you've triggered a responce from me

The Sensors aren't intellagent as such and just work on a continuity system AFAIK...

The problem you have sounds like a leaky master cylinder, or slave cylinder caused by water ingress.

Very common. Have you noticed any water inside the car at all. Check your plenum chamber, where the battery sits, for water build up due blocked drainage holes (leaves and gunk) and report back.

I'll check this thread again in the morning

Nick

[Sam]

Welcome aboard

I read your post, typed a few replies, then thought it better that someone who KNEW what the issue was should reply.

Personally, I'd say that changing brakes has no effect on the ECU whatsoever. The car is hitting limp mode for a reason, but imho that reason is nothing at all to do with you changing your pads.

Crasher is our resident VAG Geek, I'm sure he'll be in shortly to help you out.

[bora(ing) nick]

Crasher is our resident VAG Geek, I'm sure he'll be in shortly to help you out.

I'm sure he'll appreciate that descriction

[Bodferret]

The moral of all this is that he told me that the car could be in LIMP MODE as the brakes are failing.

To all you lads that have a bit of knowledge, could this be true.

Thanks mycarsavw for replying but as i stated above, the car being in limp mode was just a suggested thought by someone else, he wasnt saying it was in Limp mode....What is the exact mph for limp mode anyway. Nothing is flashing on the dash and all theories are welcome.

[Sam]

Thanks mycarsavw for replying but as i stated above, the car being in limp mode was just a suggested thought by someone else, he wasnt saying it was in Limp mode....What is the exact mph for limp mode anyway. Nothing is flashing on the dash and all theories are welcome.

I was agreeing with his diagnosis.

No warning lights could be a faulty MAF which causes a poor running, acceleration, lack of power etc

Split hoses, boost leaks, etc.

[Eshrules]

Thanks mycarsavw for replying but as i stated above, the car being in limp mode was just a suggested thought by someone else, he wasnt saying it was in Limp mode....What is the exact mph for limp mode anyway. Nothing is flashing on the dash and all theories are welcome.

first of all.... mate, chill out... people on here will help you, but not if those people who require help have an attitude

secondly, ther is not a speed limit as such on limp mode, it limits the way the car is driven, limits the revs, it just stops you driving the car normally, it is 'limp home' mode, ie, simply ticking over to get you home.

i would say with a fair amount of certainty that the loss of power/limp mode is probably not anything to do with the brake change.

the symptoms you describe are indicative of a failing maf, if your brakes are OK and without fault, let's forget about that.


the other thing of course, could be a turbo related issue.

BUT no matter what it is, if the car is in limp home mode, there will be codes logged, i would suggest a fault read asap to help establish the cause.

i would imagine crasher will be along soon to comment

[bora(ing) nick]

From the OP's first post...

About 2 days later i noticed they were getting stiff if i depressed them more than once approaching the traffic lights, to the extent that i couldnt push them in at all and the brake system failed.

I too think the OP has 2 seperate issues.... Are the brakes still the same now?

Nick

[Marco34]

I'm thinking along with eshrules. A brake would not have such an impact on your car. I changed my discs and pads and all was fine.

I'd get VAGCOM connected and check for fault codes and go from there.