you need ti find out which wheel is sticking. when was the brake fluid last changed
As above, there is no evidence reported so far that ANY wheel is sticking, though it could be.
And its a fair bet that the brake fluid was changed recently, along with all 4 calipers.
Edited by edlithgow on 08/10/2024 at 09:34
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Not familiar with the brake design on that vehicle, when the calipers were replaced were the sliders cleaned and lubed correctly on reassembly.
As above, a laser thermometer is cheap and useful for many things including this, try and drive on the open road for some distance and choose a stopping point preferably uphill or somewhere you can bring the the vehicle almost to a complete halt without touching the brakes, if there's a brake dragging sufficiently it shoudl be clear even without a thermometer if you put your fingers near (don't touch it) the brake/hub assembly.
You've checked presumably the park brake is fully releasing, same check as above.
Last serious dragging brake i saw was on the rear of a Mazda 5, so much brake material was transferred onto the wheel it proved impossible to remove using all my wheel cleaning chemicals, yet the owner hadn't a clue until i mentioned, water splashed onto the rear disc boiled straight off.
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OP, if, on investigation, you find one or more of your brake disks are seriously hot, don't go splashing water on them.
They might warp.
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Having re-read this, I now think that the OP is assuming brake involvement because he gets a sudden rise in fuel consumption, which I assume is continuously displayed, after firmly applying the brakes.
I didn’t realise this on first reading, probably because I’ve never had a car capable of displaying "instantaneous"fuel consumption
Hence my(probably incorrect) comments that there is no evidence of brake involvement.
This interpretation would seem to exclude parking brake involvement.
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As well as the hose acting as non-return possibility already mentioned, sticky/corroded slider pins (which, with a pro job, .might not be replaced with the calipers and might not be cleaned or lubricated either) might cause a hang-up.
I clean these with aluminium foil, apply silicone grease, and wrap with PTFE thread tape.
(The last PTFE is unconventional and optional. See argy-bargy and linked picture in other recent thread)
www.honestjohn.co.uk/forum/post/198391/kia-cee-d--...r
The brake calipers I'm familiar with incorporate the ledges on which the brake pads mount, and would normally be supplied with new stainless steel mounting clips on which they slide, so hang-up there with new calipers would be unlikely
I dont use any "wet" lubricant on these sliding surfaces, instead rubbing the SS clip surfaces with a 2B graphite pencil and wrapping the pad ears with PTFE tape, but some people use antiseize or brake grease here.
I dont do that because it attracts brake dust clogging which can prevent free pad movement.
I do rust treat the calipers to prevent rust jacking of the pad clips jamming the pads long term. This wont happen for some time with new calipers
Edited by edlithgow on 13/10/2024 at 14:43
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Another possibility for locking up brakes would be excessive grease on the slider pins causing build up of pressure behind the wee rubber boot things.
Mentioned by Mr O during the fairly uninteresting brake job below, about 7.5 minutes in.
www.youtube.com/watch?v=OOPVBXLyQwY
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This an update on my car brakes, since posting I have checked all brake sliders and all were working fine but to be sure all has been cleaned out and regreased with fresh silicone grease, I have replaced the drivers side front brake hose and carried on with trips but the symtoms came back again after some harsh braking so I've discounted rhs front and now changed the lhs front brake hose, as of yet nothing as happened but its still early days since the change and I have not had much use of car since. will update as I go along.
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Another update, everything has been fine until Wednesday 12/12/24 when we took a trip to Belton house in south Lincolnshire, we came around a bend and found a tail of traffic at some road repair lights, had to brake reasonably hard and found once on the way again that my problem was back as consumption was going up again, this lasted for about approx 30 miles when it started getting better, so this coming week I shall be replacing one of the rear flexies. knowing my luck it will probably be the last one I change!
regards Pecky
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Before deploying the parts cannon you could actually test for this (as I think I suggested above) using an enema syringe, (which is also useful for brake flushing and other jobs)
If you cant push brake fluid in via the brake bleeder nipple, but you can suck it out, that would be consistent with the brake hose acting as a non-return.
If you cant do either you've got a blockage, which could be in your bleed nipple, the brake hose, or your hard brake line.. You can take the nipple off to test, and potentially clear it
I suppose, though, that prematurely replacing a brake hose isn't very extravagant, as such things go
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From what i've read here you still haven't found a sticking, ie overheated, brake.
You have increased fuel consumption according to the instant readout but you don't speak of any excess brake heat or smells and to noticeably increase fuel usage the brake drag involved would be causing a lot of heat which you should by now have discovered as explained above.
Its possible indeed likely your issue is nothing at all to do with brake drag, one possibility is a DPF regen in progress, assuming Diesel, another is a sticking EGR valve though i'd expect that to put the EML light on.
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From what i've read here you still haven't found a sticking, ie overheated, brake.
You have increased fuel consumption according to the instant readout but you don't speak of any excess brake heat or smells and to noticeably increase fuel usage the brake drag involved would be causing a lot of heat which you should by now have discovered as explained above.
Its possible indeed likely your issue is nothing at all to do with brake drag, one possibility is a DPF regen in progress, assuming Diesel, another is a sticking EGR valve though i'd expect that to put the EML light on.
I thought (and said) that initially, but, as above, I now think that the OP is assuming brake involvement because he gets a sudden rise in fuel consumption, which I assume is continuously displayed, after firmly applying the brakes.
If its closely coincident in time this seems a reasonable interpretation.
I suppose its just possible that an engine upset is triggered by brake application, perhaps via demand on the vacuum servo, or some electric ghost in the EMS, but it would probably have to be something subtle and modern that I probably wouldnt really want to understand.
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I thought (and said) that initially, but, as above, I now think that the OP is assuming brake involvement because he gets a sudden rise in fuel consumption, which I assume is continuously displayed, after firmly applying the brakes.
If its closely coincident in time this seems a reasonable interpretation.
I suppose its just possible that an engine upset is triggered by brake application, perhaps via demand on the vacuum servo, or some electric ghost in the EMS, but it would probably have to be something subtle and modern that I probably wouldnt really want to understand.
Maybe time for someone to interrogate the OBC, thought it would be most useful to have live data when these episodes happen.
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