car.crash

Hi my 2003 mondeo tdci has terrible brakes. I bought the car with the abs light on and the brakes seemed ok. I fitted a new abs sensor and cleared the fault code and now my pedal is hitting the floor and is very spongy.
I'm pretty sure its coincidental though.
The car has good discs and pads and no leaks on the brake lines that I have seen.
I pressure bled them twice and its made only a slight improvement and somtimes the pedal feels ok and others very soft.

Any ideas what's going on?

martysmartie

iTrader: (1)

Sounds like a faulty Master cylinder, perhaps.

Martin

dojj

iTrader: (3)

Master cylinder seconded by me

DanW@FastFord

iTrader: (1)

If the pedal is sometimes hard, and sometimes soft it may be nothing to do with the brakes as such.

Take the wheel off and see if the hub nut is tight. If it's not, then tighten it (280Nm I think) if it comes loose again you need to replace the hub flange otherwise it will keep happening, and also start to take out wheel bearings with it.

DanW@FastFord

iTrader: (1)

Here's a pic of a hub flange, and where they wear...

car.crash

I'm also getting a wheel bearing failure noise. Went round the wheels today and wobbled them but felt nothing.
I also pulled all the wheels off and made sure the pads were sitting flush on the disc and not caught on any lips.

Could the wheel bearing noise be the hub nut coming loose?


EDIT
Just checked the fronts and they are both properly tight. Can't do the rears yet as the dust covers were hiding the nuts.

DanW@FastFord

iTrader: (1)

Did you jack the car up and waggle the wheels? If there's a wheel bearing noise as well, then it definitely points to the hub flange.

If the brakes are depressed it pushes the pads together and takes up the 'slack' caused by the worn flange. Hence why the brakes sometimes feel fine, and at other times very soft with a very long pedal.

car.crash

I did try that but failed to notice any play, but the noise is loud and certainly points to a failed bearing and the pedal is not right.

I will remove the rear wheels and dust covers tomorrow and check they are tight.
I spun all 4 wheels as well whist the car was jacked up but I failed to notice a difference in any of them by sound or feel.

Thanks for all the help so far, I appreciate your efforts in helping me here.

DanW@FastFord

iTrader: (1)

it won't be the rears, or at least I very much doubt it will be. Jack up the front, grab the wheel top and bottom and properly waggle it to see if there is play. There may not be much movement, but if you're getting a randomly long pedal, and a wheel bearing noise then it's got to be the culprit.

car.crash

I shall try and do it tonight if I get time.
There is a horrible hum coming from somewhere.
I will check google now on what's involved with a bearing swap as well.

I shall report back if I find any play

DanW@FastFord

iTrader: (1)

Unless you have a very big press then I wouldn't do the bearings yourself – It's a pig of a job getting them back in properly. If you want to save cash either take the whole hub assembly off and take them to a garage to press the old ones out, and new ones in. Or take a gamble and buy a complete hub from eBay. If the hub nuts are fine, and there's no excess movement in the flange, then you could get away with just bearings.

But be careful that it is just a bearing and not a flange too - I replaced one of the bearings twice before realising that the flange was worn, so ended up doing the job three times in a month!

car.crash

I have access to a few presses through friends.
I've got a starter motor going on today then fingers crossed I can sort the bearing noise.

I should have know not to buy a car that's been chopped in on part x

car.crash

Okay so the starter is now fixed.

On the brakes we jacked up each wheel and couldn't find any play or hear any noise to give us a clue to what bearing is faulty.
But when I drive there is a loud and distinct rotational rubbing noise.

Also on the brakes I was advised it was air in the lines despite my pressure bleeding, he said it may be stuck in the abs pump, so he took my car on a loose surface and was hitting the brakes hard and he claims that will push air out of the abs pump when the abs system starts working hard?
i was advised that I should now pressure bleed it again to remove what air has moved from the pump to the lines.
The brakes are better than they were when I started the thread but still not great and the horrible bearing noise is still there.
I'm baffled on it.