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Discussion Starter #1
When i turn off the car there is a weird electrical clunk/rattle noise but only happens after i've been driving in traffic (alot of stopping and going) and when i start the car afterwards it doesnt start st8 away, takes 2 to 3 seconds longer. But if i leave the car overnight or for 7hrs or so, everything is alright. There isn't any problems when im driving.
If i drive in less traffic then i dont hear the noise when i turn off the engine and have no problems when i start the car again.
Does any1 know wat the problem may be?
 

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WTF is an ABS pump then and WTF does it do ? I thought I knew how ABS worked but now you have me thinking :wub:


I think the 2 simptoms are not related

the ticking noise could just be the exhaust system/CAT cooling down and contracting as they can get very hot in traffic

the poor hot starting could be an engine temp sensor failure (do not confuse this with the radiator coolant temp sensor)

if this sensor fails the car thinks the engine is cold when it is not and goes into cold start mode, if you remember cars with a choke nob or maybe an auto choke it's like tsarting a hot engine with the choke on
 

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VXon Frontera Monkey
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Hi on cars with ABS there is a pump that pressurises the ABS brake lines so when you need the ABS you don't lose the brake pressure after you turn off the engine the pump relay releases the pressure to avaoid damaging internal components most are silent but as they get older i suppose the get noisy
regards
Steve
 

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must be some mighty strange abs systems on vauxhalls then, nothing like the abs systems I know about

the idea of abs is to loose pressure

no pumps on them, the brake lines are presurised by your foot on the pedal and when the encoder sensor sees no pulses from a locked wheel a solenoid valve chatters very fast and pulses the pressure that you have applied from the pedal

when the solenoid valve pulses the brake line pressure is reduced so as to unlock the skidding wheel

no pump involved at all unless you class the servo as a pump but that is just a vac diaphram
 

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VXon Frontera Monkey
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Hi just curious where you get your info about ABS systems there is no way on the planet your foot would produce the pressure required to work an ABS braking system all and i mean all ABS equiped cars have a high pressure ABS pump and associated pipework you maybe under the false impression that ABS releases your foot pressure on the caliper and then re-apply it but in reality the brake is applied and released by the ABS pump/modulator when the combination of foot pedal and sensor and locked wheel combine you would never be able to apply at the speed required and the pressure you apply with the foor brake wouldn't be enough to supply the amount of times it is applied thats why they have ABS pumps
Here is a good link to an in depth explaination note the bit about 'ABS PUMPS'
http://www.dashdriving.com/tutorials/abs.htm
regards
Steve
 

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***VxON Photographer of the year 2007***
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must be some mighty strange abs systems on vauxhalls then, nothing like the abs systems I know about

the idea of abs is to loose pressure

no pumps on them, the brake lines are presurised by your foot on the pedal and when the encoder sensor sees no pulses from a locked wheel a solenoid valve chatters very fast and pulses the pressure that you have applied from the pedal

when the solenoid valve pulses the brake line pressure is reduced so as to unlock the skidding wheel

no pump involved at all unless you class the servo as a pump but that is just a vac diaphram
well sorry mate as the ford system has a pump too :lmao:

i know as they cost a fortune and i had to scrap an old Granny due to the pump failing and me not wanting to put a second hand one on.

Let Me explain to you how it works and what it's for.

with a non ABS system the foot presses the peddle then the master cylinder pushes fluid to the brake caliber hence pushing the friction plate ( brake pad / shoe ) onto the disc / drum. THe resulting reistance causes the whell to slow and the car to stop.

Now if too much presure is put on a wheel and the wheel loses traction with the road the wheel locks and you skid.

Now with an ABS system a sensor noticed the wheel lock and for a fraction of a second releases the caliper to let the wheel turn. The problem with this is the pressure of the system will drop unless there is a reserve of pressure to push more fluid to the caliper. This is done with the use of a pump sending fluid to the acumulator. Hence the system always has more than enough presure to carry out several anti lock cycles before the pressure drops to a level where the system will not work.

After driving with hard braking it is not unusual to here the ABS pump running after you stop. You don't normally notice it due to the fact that engine , fans ect drown out the noise.

No this is not just Vauxhalls it is ALL ABS systems without the pump the system will not work




here mate it's all expalined here

http://auto.howstuffworks.com/anti-lock-brake1.htm
 

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VXon Frontera Monkey
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Hi as explained you have no problem if the ABS warning light comes on and goes out all is fine unless you do an indepth feel and listen we can't help anymore i think we have given quite a few answers about what it could be more than that i don't know what you want us to do the ball is in your court now to use the info we have supplied and if you find it then please post back so others will know
regards
Steve
 

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must be some mighty strange abs systems on vauxhalls then, nothing like the abs systems I know about

the idea of abs is to loose pressure

no pumps on them, the brake lines are presurised by your foot on the pedal and when the encoder sensor sees no pulses from a locked wheel a solenoid valve chatters very fast and pulses the pressure that you have applied from the pedal

when the solenoid valve pulses the brake line pressure is reduced so as to unlock the skidding wheel

no pump involved at all unless you class the servo as a pump but that is just a vac diaphram
whaaaaaaat?:mmmm
 

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must be some mighty strange abs systems on vauxhalls then, nothing like the abs systems I know about

the idea of abs is to loose pressure

no pumps on them, the brake lines are presurised by your foot on the pedal and when the encoder sensor sees no pulses from a locked wheel a solenoid valve chatters very fast and pulses the pressure that you have applied from the pedal

when the solenoid valve pulses the brake line pressure is reduced so as to unlock the skidding wheel

no pump involved at all unless you class the servo as a pump but that is just a vac diaphram
so is this " abs pump" the cause of this electrical noise then ? :bananasmi
whaaaaaat? :eh
so what systems do you "know about"?
you drive an astra elite? have a look under the bonnet and tell us all what YOU think the thing with all the brake lines coming in and out is? most people who "know" abs systems would say its a pump but since you know best please enlighten us?
i'd also say it could be the ABS pump or the fuel pump and/or relay getting hot.
 
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