Totally stumped with Toyota Aygo brakes

[Dave1000rr]

First of all as a new member I am so glad to have found this forum. I have recently bought a Toyota Aygo 2014 reg with 48,000 miles on the clock. I have an issue with brakes. The majority of the time I have to double press the brake pedal to get them to work effectively. On the first press of the brake pedal it travels a long way down and you can feel a pulling to the right once pressed again all seems okay. I have checked all the brake lines and there are no leaks. Have checked the front pads and discs and all are good. Do notice that the drivers front caliper bleed screw had been rounded at some stage. So have fitted a new caliper. Have bled all four brakes. The rear shoes look fine. But still encountering the same problem, wondering on your thoughts of what to checkout please.

[Xanadu_999]

Could be the brake master cylinder, but at 48,000 miles it would be unusual for this to happen.

[TriumphMan]

The symptoms you describe are usually associated with air in the brake fluid or very worn front pads - it could (although less likely) be the servo.

if you put your foot on the brake and you feel the pedal gradually drop it may indicate master cylinder as previously mentioned.

Definitely worth have a closer look sooner rather than later.

 

[Bper]

Hi David,Based on what you are describing having to double press the brake pedal and the car pulling to one side the likely issues are either air trapped in the brake lines or a faulty master cylinder.Even though you've bled the brakes, it’s possible there’s still some air trapped in the system. This can cause the pedal to feel soft or spongy, and sometimes you’ll need to pump the pedal to get proper braking power I’d suggest re-bleeding the brakes, making sure to follow the correct order that way, you can be sure you’ve gotten all the air out.If the master cylinder is worn out, it might not be able to hold pressure properly. This would explain why the first press feels weak, but the second press works better.If re-bleeding the brakes doesn’t fix it, then it’s probably time to check or replace the master cylinder.I’d start with re-bleeding the system, and if that doesn’t help, the master cylinder is the next place to look.👍

[TriumphMan]

I forgot to add, if you re-bleed the brakes and they are still spongy you could try an old-school technique;   Jam the brake pedal fully depressed as far as it will go by using a broom handle (or simlar) between the pedal and the drivers seat.

Leave it that way overnight, longer if possible - this will remove the sponginess. If it doesn’t improve things you likely have a more significant hydraulic issue.

[Dave1000rr]

Thank you for all the replies it is much appreciated. The front pads are nearly new. I am going to rebleed the brakes as suggested and see if there is an improvement. I believe the correct order to bleed is rear left, rear right, front left and front right. Look forward to hearing back.

[flash22]

Order does not matter really as it splits at the abs pump. When you noticed this issue was the fluid level dropping and you were topping it up ??

Mk1 or Mk2 aygo

Are the brakes hard, as in the amount of pedal pressure it takes to stop the car?

[Dave1000rr]

Hi flash22, it is a MK1 Aygo. Nope the fluid level does not drop. Sometimes the pedal is hard and quite often the brake movement is excessive within a inch of the floor with a sponge feel.

[Dave1000rr]

Have re bled the brakes, rear ones and front left bled fine. Noticed when attempting to bleed the front right with tube connected and loosened the bleed nipple a quarter turn when pumping the brakes getting a dripping of brake fluid on underneath of caliper and not pushing fluid to the container. When the bleed nipple is tightened there are no leaks so I am assuming it's coming from the bleed nipple threads, this is a new caliper. Any thoughts please

[flash22]

could well be a bad caliper or a bad hose

 

because it's new doesn't mean it's good

 

are you using an ez-bleed kit, vacuum or the 2 man method with a pipe and fluid

[Dave1000rr]

Using an ez bleed kit. 

[TriumphMan]

Personally, I have never had much luck with easibleed - I have to sweet-talk my wife to do the pedal-pressing. 
When doing it manually you can also do different speeds of pedal-pressing which can help shift stubborn air pockets.

that said, if you have leaks, they need to be resolved first, be it caliper or pipe work or joints

[flash22]

If the threads are leaking fluid, they can also suck air

Silly question, is it the correct caliper with the bleeder to the top LH caliper on the RH or vice versa

 

A vacuum bleeder is what I have had most success with, a drop of fluid in the cup to start with

 

[Dave1000rr]

It is the correct caliper with the bleed nipple at top

[Dave1000rr]

Been on holiday so just to give you an update. Took the Aygo to Halfords for a free brake check. They bled both front calipers and said there was air in the lines. But no change the brake more often than not have to be double pressed to get good feeling in the pedal. On first press the pedal is very spongy and travel is excessive and when this happens you can feel the car pull towards the right. Really stumped on this one and garages are useless.

[southsider46]

On 9/8/2024 at 4:58 PM, Dave1000rr said:

when pumping the brakes getting a dripping of brake fluid on underneath of caliper and not pushing fluid to the container

Make sure the bleed nipple isn't blocked and that you are opening it enough for the fluid to flow freely.

[flash22]

find a garage that does MOTs and ask for a brake test (usually a set of rollers) that will find the wheel with the issue (brake imbalance)- any change if you pull on the hand brake (button in) when braking

The only other things that come to mind,

a junk calliper, because it is new, doesn't mean it is good,

A flexible hose is failing internally on the fronts or rears

 

[Stecha]

13 hours ago, Dave1000rr said:

Been on holiday so just to give you an update. Took the Aygo to Halfords for a free brake check. They bled both front calipers and said there was air in the lines. But no change the brake more often than not have to be double pressed to get good feeling in the pedal. On first press the pedal is very spongy and travel is excessive and when this happens you can feel the car pull towards the right. Really stumped on this one and garages are useless.

Sounds like possible Master Cylinder wear.

[Dave1000rr]

Been on holiday so just to give you an update. Took the Aygo to Halfords for a free brake check. They bled both front calipers and said there was air in the lines. But no change the brake more often than not have to be double pressed to get good feeling in the pedal. On first press the pedal is very spongy and travel is excessive and when this happens you can feel the car pull towards the right. Really stumped on this one and garages are useless.

[Dave1000rr]

The Aygo has only covered 50k miles and been serviced every year. Would the master cylinder wear with that mileage

[TriumphMan]

21 minutes ago, Dave1000rr said:

The Aygo has only covered 50k miles and been serviced every year. Would the master cylinder wear with that mileage

Quite possibly, rubber seals don’t last forever.

[Stecha]

21 hours ago, Dave1000rr said:

The Aygo has only covered 50k miles and been serviced every year. Would the master cylinder wear with that mileage

If its stop start city driving, or similar, then quite possibly, yes

[Stecha]

Just now, Stecha said:

If its stop start city driving, or similar, then quite possibly, yes

Also, how often was the brake fluid changed ?

[bobby boy]

Air trapped in the ABS?

[Dave1000rr]

The cars been serviced annually from new does the 2014 model have ABS. Would it not throw a light on console