Brake booster change caused ABS line clogged on front left wheel

[riztauras]

Hi Guys,

I had to change the brake booster/master cylinder assembly of my Vitz 2005 due to braking issues, I purchased the whole assembly of brake booster and master cylinder from Shafiq Mor Karachi, Azhar Autos. The mechanic didn't pay attention to cleaning of brake oil bottle attached to master cylinder, it was dirty and filled with debris/dirt, I pointed it out this on which they just superficially cleaned the bottle, so they fitted the assembly and bleed out the lines, I felt the brake pedal was very hard, but I can still apply brake and stop the car, I thought maybe it was due to new brake shoes, (they also told me to change the rear brake shoes as they were about to wear out), so I left the workshop and when I speed up the car above 60Km/h, the car was not properly responding to braking and it even skid to one side, I got it checked from a mechanic nearby home, he told me that on the front left wheel there is no brake fluid coming out of line when he tried to remove air, it was completely clogged.
I went again next day to the same brake wala guy and he checked the line and told me that your flex pipe is clogged, get it changed, I let them do it, it doesn't help, so they checked the line all the way to ABS distribution lines and found that the line for front left wheel is clogged which is coming from inside the ABS.
(It was completely fine until they installed the debris filled bottle of master cylinder, I argued with them but they don't accept their mistake as usual of what we know about these Kanjar class mechanics, giving me lame explanations, and now they are asking me to change the whole ABS assembly because the ABS can't be unclogged/repaired, so I have to replace it.
I didn't trust them anymore so I left the workshop to find somebody honest to get this thing done.
Can anybody tell me if there is a way around to unclog one of the lines, or ABS system has to be replaced, My car is skidding to one side in emergency brake, due to only one wheel of the front side is getting brake fluid pressure.
Please I need expert advice if anyone knows about it.

[murtazamohammad54]

I know a good mechanic who can be of assistance. He may also be able to come over to your place to help you out as well. Message me if you want details about his contact. Don't drive your vehicle to be on the safe side as it is quite a serious risk driving in this condition.

[sleeper]

Riztaurus.....This mechanic is at Azhar autos? Pls share where he sits/his shop is so that others dont ruin their cars.

[riztauras]

Yes , its Azhar autos, Shafiq mor old spare parts market, main road, opposite side of Banks line. Don't ever go to them.

[riztauras]

@Xulfiqar bhai, I am told that you are knowledgeable about cars, can you please advice the way forward.

[muh_farooq]

Xulfiqar is against used jdm cars, also scrapyard parts

[Xulfiqar]

did your mechanic bench bleed the master cylinder? and was it verified that both hydraulic circuits of the master cylinder are good?

If debris really clogged it then you can try unclogging it by removing the the offending hydraulic line from the ABS distributor and tapping the distributor block with a soft and small hammer, then see if you can get fluid to flow out of it. If you cannot get anything out of it - its bad and you need a new ABS distributor unit (which usually is a pain and a half)

[margallar]

@Xulfiqar

Does vitz not need a scanner to open the valves of abs system, during bleed?

[Xulfiqar]

the final purge requires cycling the valves to get everything out and also test that the valves are not stuck, but in default inactive state the ABS block is freeflowing, it only "closes off" hydraulic circuits when commanded.

[riztauras]

I just watched a video on bench bleeding, no he did not bench bleed the master cylinder, rather only bleed the lines after installation, the oil was coming out during that time from the now offending line, but after some running of car it was clogged, I felt it when the car skid on one side when I was testing emergency brake and ABS function integrity. I will give it a try by tapping the ABS distributor with a soft hammer. thanks for the suggestion, and shall update accordingly.

[Xulfiqar]

bench bleeding is mandatory when installing master cylinder - in Pakistan they used to call it "haath wali pumping" or "haath se brake banana"

and because you bought a scrapped cylinder, then its probable that one circuit on it is bad (toyota use X split brakes)

are you getting fluid pressure at the diagonally opposite wheel or not?

[riztauras]

good point, I was getting the fluid at both rear wheels at that time, will check again tomorrow.

[Xulfiqar]

how much fluid was pumped through the system? it takes about 1 litre to flush a car with 4 wheel passive ABS.

[riztauras]

@Xulfiqar bhai, Today I went to the mechanic he checked the ABS with tapping with hammer and also tried vacuum suction with a syringe and pipe, it didn't work, the fluid is coming out of that ABS line but the stream is very weak, not enough pressure to press the calipers, for now the mechanic used a "Tee" to split one of the hydraulic line coming from the Master cylinder with one outlet going directly to the front left wheel, and other outlet going to the inlet line of ABS and the outlet line from ABS which was supposed to go the front left wheel is sealed off.
Now although braking is working fine, the ABS system which should track the other 3 wheels locking, is completely unresponsive, I don't understand what happened to ABS now, its not working at all and now I have a brake with any other car without ABS system.
Do you have any idea what happened to ABS, why is it now totally unresponsive and there is no ABS warning light on dashboard.? It was doing its function before using this "Tee valve" to supply fluid directly to front left wheel.
The mechanic is saying to find its ABS and replace it.

[Xulfiqar]

Looks like you have a clown for a mechanic

Syringe and pipe to apply vacuum on an ABS pump, Hahahhaah, and then installing Tee before the ABS distributor - holy cow, hes suicidal.

the reason your ABS is not functioning anymore is because the input pressure has been relieved. Please dont let such people work on your cars brakes - specially people who are busy screwing with Tees and other BS - find its ABS distributor and install it properly.

[riztauras]

Hahaha, anyway can you please look at the sketch, Input pressure is not completely relieved, although it is distributed before entering the ABS unit.

@Xulfiqar bhai can this configuration cause the ABS unit to stop functioning?
Actually I had not enough time today to find the distributor within a day and get it installed so he just made a quick fix until I find this ABS unit , I will find this part in next week as the week is about to end and get it installed from some professional with experience on ABS brakes.

[Xulfiqar]

Yes it will cause it to stall

Please stop doing such experiments, and remember that all toyota use X split brakes

Plumbing them by bridging T joints is literally suicidal and is actually prohibited in developed countries

[riztauras]

Hello All.
I finally found the ABS unit of my vitz and replaced it. My problem is resolved now. ALHAMDULILLAH..!
But before replacing ABS unit I had to change the master cylinder and brake booster as well.
Because I came to know from other mechanic that the previous guy (Azhar autos shafiq mor) installed the brake booster and master cylinder assembly of any other car.
Which is currently I have it and upon inspecting it.
Look what I found under the bottle reservoir inlet on one of the inlet line is filled with debris, its not just dust its kind of crush that we call bajri in urdu.
Now I am completely sure that guy ruined my ABS with this.
Beaware of these kind of mechanics I learned it the hard way.