9n TDI polo brakes problem

Post Reply
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

9n TDI polo brakes problem

Post by RJ8V »

Hi guys,

So about a few months ago we noticed that our 2005 1.9TDI 96kw polo brakes are only starting to take when pressed in almost half.

This past weekend I replaced all pads at the rear and front as well as new discs infront as it had a slight shudder.

Bled as per normal and must say handbrake has improved due to new pads at the back. But the brakes still only starts to work when pressed almost halfway. This is a bit scary to drive. On my google search I read somewhere one must bleed the abs pump with vcds. I got the program, how does one do it and will this solve my issue? I want to start feeling the brakes the moment you press on the pedal.
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
panic-mechanic
Panic's Place
Posts: 26715
Registered for: 21 years 7 months
Membership No: 79
Location: Benoni, putfontein.

Re: 9n TDI polo brakes problem

Post by panic-mechanic »

is the pedal low when you have the engine off or does it drop when you start it only. Did it change over time or was it always like that.
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

No pedal at normal position. It started overtime as stated. So I replaced pads and discs. Bled the old way. No change. When I apply brakes, I almost have to press it in halfway before I can actually feel the car starting to brake.
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
panic-mechanic
Panic's Place
Posts: 26715
Registered for: 21 years 7 months
Membership No: 79
Location: Benoni, putfontein.

Re: 9n TDI polo brakes problem

Post by panic-mechanic »

if the pedal is good high and hard when there is no vaccum assist then bleeding etc is not the issue.
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

Okay now I am with you Stephan. Pedal is not hard when car is switched off eventough ot is high. And as per normal when I start the car, pedal is soft but takes way low.
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
panic-mechanic
Panic's Place
Posts: 26715
Registered for: 21 years 7 months
Membership No: 79
Location: Benoni, putfontein.

Re: 9n TDI polo brakes problem

Post by panic-mechanic »

I have never had to bleed brakes by activating abs. When abs is not working / intervening it is simply a pass through of fluid.
So either maybe you are not quite doing the bleeding right and inadvertently letting air back in - you have to watch the fluid bottle like a hawk.
get the brake pump person to do multiple pumps before every opening of the bleeder and make sure they don't lift until you have definitely closed the bleeder.
It is also possible that your master cylinder is leaking. Have you had to top up fluid at all. When there engine is not running and you stand on the pedal does it move away at all - or does it stop and stay.
Mushy pedal with no vacuum indicate air in the system somewhere
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

When car is stationed and switched off. The pedal is hard yes but if I press the pedal hard down I can feel that it is not staying there. Slowly getting low up till a point where it stays.
Bled was done perfectly IMO. Bottle never reached low and I bled untill only brakefluid came out. But you got me thinking here, as it started to feel like this some time ago and the new brake pads and bled this past weekend changed nothing. Only handbrake is stiffer and pads are fresh
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
Ashveer03
Lieutenant
Posts: 1621
Registered for: 7 years 1 month
Car Make: VW
Car Model: Polo 9n 1.9 TDI Sportline
Location: Durban

Re: 9n TDI polo brakes problem

Post by Ashveer03 »

Seems like the system is letting go of the pressure somewhere along the line..

Did u notice when cracking open any of the bleading nipples, that the pressure that the fluid comes out is maybe less than the others?

Has ur brake fluid ever been replaced? Contaminated brake fluid is the last thing u want.

Are any of the calliper pipes not twisted..?

Sent from my SM-J500F using Tapatalk
When a car tailgates me, i slow down - then floor it and give them a cloud of diesel smoke to choke on :driving:
User avatar
panic-mechanic
Panic's Place
Posts: 26715
Registered for: 21 years 7 months
Membership No: 79
Location: Benoni, putfontein.

Re: 9n TDI polo brakes problem

Post by panic-mechanic »

if the pedal gives way then you have a leak or you are compressing air.
Stephan van Tonder - Jhb - Putfontein Benoni
'05 Audi A6 3.0L TDI Avant
'09 Touareg 3l TDI
'13 VW CC 2l tdi (repair project)
'05 Touareg v10

Perfect Power dealer. I do dyno tuning.
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

Okay so the abs bleed via vcds wont solve this one. No leaks at calipers or near them so all hoses and nipples still good. Where else can I look for a leak?

Shouldnt the brakefluid bottle have shown me that a leak is the culprit? I didnt had to fill up, level was and still is at max line, only topped up when I was bleeding the brakes
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

Hi just an update. Or let me rather start fresh to avoid confusion.
As this bothered me so I quickly went in my garage and had a look.

Panic the brakes are hard and remain hard if I press it in when the car is switched off. Sorry for the confusion.

So I did the abs pump thing on vcds where the pump is priming and telling you to press or depress and output test came out clean also no faults on abs.

Started the car. Brakes still go halfway before it actually starts to brake and if I press it in and hold it in when car is idling it slowly goes mushy.

See no visible leaks near calipers or at the brakefluid reservoir.
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
RJ8V
Cadet
Posts: 251
Registered for: 8 years 8 months
Car Make: Mazda
Car Model: BT 50 3.2 SLE 4x2
Location: Mpumalanga, Middelburg

Re: 9n TDI polo brakes problem

Post by RJ8V »

I guess I will have to do the fully abs bleed procedure on vcds and after thst the normal manual bleed on all 4 wheels. Then check again
EX: '02 AUDI A3 1.8 20V
EX: '81 Golf Rabbit Mk1, 2e 8V MP9. Not self-Build.
EX: '05 Ford Fiesta ST 2.0 Normal Aspirated
EX: '06 Volvo S60 D5
EX: '79 Golf MK1 2Door, 1.6i MP9. Not self-Build
EX: '05 Golf Chico 1.4 Carb - Self- Project

Image
User avatar
Deranged_9n3
Darth Vader
Posts: 5572
Registered for: 13 years 3 months
Car Make: VW
Car Model: Polo 1.9TDI Sportline
Membership No: 1639
Location: Montana Park
Contact:

Re: 9n TDI polo brakes problem

Post by Deranged_9n3 »

Check the air/vacuum line on your tandem pump going to the abs pump. Tandem pump is on the opposite side of the cambelt next to the motor. Line sits at the back. They have a tendency to wear out and cause an air leak if you have the older type. Newer type has different fittings that are alot more ridgid
My Youtube Channel

Tiguan Track & Field 4Motion

20" Rotors l Airlift Performance l 63mm Downpipe and DPF Delete l PD-Tuning Software

Polo TDi RaceCar

GTB2260VZK l 76mm Stainless DP and FF l FMIC + Stainless Boost Pipes l Nitrous l PD-Tuning Software

GTB2260VZK
13.2 1/4mile @ ODI

Image
Loud 'n Low, Rollin' Coal
Post Reply