Car just failed MOT - Likely cause/fix/cost

stoofa

stoofa

stoofa

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Hi All,
I'm a little out of practice on all this - being lucky enough to keep my own car relatively young, I'm not used to seeing a car fail an MOT.
My wife's 2008 VW Polo has just failed it's MOT. First time in it's history it hasn't passed first time. 55k miles on the clock and it has failed with:

Service Brake efficiency below requirements (1.2.2 (a)(i))
Rear Brakes imbalanced across an axel 2 (1.2.1 (b)(i))

I know, an impossible task to tell me what is up. However, based on the car and age, can anyone give me a likely cause of the fail and what it's likely to cost to put right?
Plan on replacing the car with something newer in around 6 months time, so not looking to spend silly money on it.

Cheers All.
 
Service brake efficiency isn't the handbrake it’s the normal service brakes..

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It’ll likely need either the brake shoes replacing or adjusting.
It could also have a seized/leaking wheel cylinder so one side isn’t as efficient, hence the failure.
At the worst it’ll be a set of shoes and two wheel cylinders.
Assuming that it has drums/shoes instead of pads and discs, which it probably has on that car.
Not an expensive job.
 
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Does not look like it sees a lot of miles.

Hard to say exactly without stripping it down, with a bit of luck, might just need the hubs opening and a bit of a clean up of the shoes and an adjustment, maybe a cylinder replacing. Feels like a 2008 polo is drum rear brakes.... if callipers different story could be more pricey.
 
Cheers all.
99% sure it's drums on the rear.
Doesn't sound like it's going to be silly money.

It is low mileage - old lady had it before us and there are a couple of years where there were only 1000 or 2000 miles between MOTs.
Low mileage - can be great, but I guess can also be a curse when the car sits idle for long periods. My better half is putting around 1k a month on it these days.
 
probably a dodgy rear cylinder, they'll be cheap as chips. The rear brakes might just need stripping down and cleaning and lubricating again.

I wouldn't have thought anything on the rear brakes for that kind of car can be that expensive.
 
can you determine from the detailed brake tester report where the problem probably lies ?
(last week my MOT guy gave me a report showing kgf force of service brake on each corner and tolerances for values & imbalance )
 
The rear imbalance will be because there's more than 30% difference across the rear axel, such as..

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which will lead to..

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Including a fail because the service brake efficiency falls below 50% (this an example of a 2008 car, ie the OP's, a car registered after 01/09/2010 is 58%)

If the rear wheels lock out then imbalance and efficiency doesn't matter, it'll pass regardless of the KG force.


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You can have 1KG per wheel and if they all lock out, then it'll pass.

If there's anymore questions, please ask later when I haven't got a life altering hangover :(:D
 
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stoofa said:
Hi All,
I'm a little out of practice on all this - being lucky enough to keep my own car relatively young, I'm not used to seeing a car fail an MOT.
My wife's 2008 VW Polo has just failed it's MOT. First time in it's history it hasn't passed first time. 55k miles on the clock and it has failed with:

Service Brake efficiency below requirements (1.2.2 (a)(i))
Rear Brakes imbalanced across an axel 2 (1.2.1 (b)(i))

I know, an impossible task to tell me what is up. However, based on the car and age, can anyone give me a likely cause of the fail and what it's likely to cost to put right?
Plan on replacing the car with something newer in around 6 months time, so not looking to spend silly money on it.

Cheers All.
Click to expand...

Is it drums in the back?

If it's drums on back there's a high chance it's a leaky wheel cylinder.

If it's discs, it could be a sticky caliper which may free off when taken apart and lubed up
 
Probably worth doing if the car has a small engine with that milage and with the up-coming hikes in vehicle duty, it'll get a reasonable price*

*Obviously not if it looks like Father Ted's Cortina :D
 
You could do that yourself if you did a bit of research.

I'd 100% give that a go.

Edit: actually that same thing happened to a mate who had an old polo so possibly quite a common issue, which means they'll be tons of parts and tutorials for doing it.
 
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Hi all - I've now got the paperwork back from my better half.
The flagged part is:

Left (kgf)
Rear: 79

Right (kgf)
Rear: 224

Confirmed it is drums at the back.
Last question - why couldn't they stick to "offside" and "nearside"?
I'm assuming "Left" is as I'm looking at the front of the car. So, Offside?
 
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