Help with ABS

[Chef818]

Good evening, my donor is a 2003 WRX wagon. Had 63,000 miles. I kept the ABS. One issue I had was I over tightened a brake line and flattened out the connection to the ABS pump, so I bought a used unit. During the build the ABS light would not go out until I had all the lights up and running. Now when I turn on the car the ABS light goes on and shortly turns off. Unfortunately under hard braking coming up to a stop sign I found out it does not work as the front right wheel locked up. All 4 wheel sensors are installed, tone rings and the ABS G sensor. Did anyone else have an issue and what was your solution to solve it. I check the trouble codes and nothing comes up for the ABS system. Not really sure where to start to trouble shoot. Is there a way to test the pump to see if it is working? I would think that is the ABD light goes on and the off when you are turning on the key then the system has ran and found no issues with the ABS system. I do have an EJ207 Ver 7 with its ECU that has been tuned to run on 91 octane. Any chance that would be an issue? Unfortunately I have the interior mostly finished with center consul in, etc and don’t enjoy the thought of having to take it apart to chase wires, which was my least favorite part of the build. Did removing the cruise control or other non necessary System cause my issue? Any input would be appreciated, thank you

[Bob_n_Cincy]

Good evening, my donor is a 2003 WRX wagon. Had 63,000 miles. I kept the ABS. One issue I had was I over tightened a brake line and flattened out the connection to the ABS pump, so I bought a used unit. During the build the ABS light would not go out until I had all the lights up and running. Now when I turn on the car the ABS light goes on and shortly turns off. Unfortunately under hard braking coming up to a stop sign I found out it does not work as the front right wheel locked up. All 4 wheel sensors are installed, tone rings and the ABS G sensor. Did anyone else have an issue and what was your solution to solve it. I check the trouble codes and nothing comes up for the ABS system. Not really sure where to start to trouble shoot. Is there a way to test the pump to see if it is working? I would think that is the ABD light goes on and the off when you are turning on the key then the system has ran and found no issues with the ABS system. I do have an EJ207 Ver 7 with its ECU that has been tuned to run on 91 octane. Any chance that would be an issue? Unfortunately I have the interior mostly finished with center consul in, etc and don’t enjoy the thought of having to take it apart to chase wires, which was my least favorite part of the build. Did removing the cruise control or other non necessary System cause my issue? Any input would be appreciated, thank you

Chef818,
First: Congrat on getting your build this far.
The OEM brake line plumbing has one side of the MC goint to FR and RL. The other side of the MC goes to FL and RR. Most here have without ABS split the mastercylinder front/rear.
Does your plumbing follow FFR manual or OEM conffiguation?
If this is the problem, it migh be as simple as swaping some pins in the ABS pump connector.
Bob

[Chef818]

Bob, thanks for the reply. What I have is the front top connector on the master cylinder going to MC2 and the one on the back side going to MC1, is that the correct orientation? Also to make sure I am doing this correct RR would be rear right, with the perspective of looking at the car from front to back (RR could also be driver side rear) and the same for the front? Thank you for your time
Kurtis

[Bob_n_Cincy]

Bob, thanks for the reply. What I have is the front top connector on the master cylinder going to MC2 and the one on the back side going to MC1, is that the correct orientation? Also to make sure I am doing this correct RR would be rear right, with the perspective of looking at the car from front to back (RR could also be driver side rear) and the same for the front? Thank you for your time
Kurtis

Here is a picture on which port goes where. Righthand RH is the passinger side here in the USA.
The inlets don't really mater becaus the same pressure and volume come out of both.
The wheels are important so the right rear sensor and right rear brake line go to the same place.

abs.jpg


Here is a link to the ABS document out of the subaru manual.

https://1drv.ms/b/s!AgduxxAs3q-xg3dt...AmUxs?e=RxB3hT

https://1drv.ms/b/s!AgduxxAs3q-xg3kS...PnfrN?e=Tvu6kc

On a side note. I would try to get your brakes balance with with the ABS unpluged. The last thing you want is an abs fault and then not being able to stop.
Bob

[Chef818]

Got it on the brake line orientation. It looks like I have them backwards, as I have the RR and FR going to the drivers side and RL & FL going to the passenger side. I will switch them over on my next days off. There goes my nice bends and bleed the system for like the hundredth time. For a long time my brake pedal would be nice a firm when bled and then would slowly get soft, same when driving, I could pump it up and then is would slowly go to the floor. I eventually changed out the master cylinder (not fun with windshield on and car mostly finished). It did not solve the issue. It is a bummer when the problem is smaller than that after you go through all that work. What had happened was when I painted the calipers I got some paint where the copper washers / banjo fittings go for the brakes, so it was not getting a good seal. I also switch out the pads to the EBC yellow stuff and made a big difference. The next thing I am working on is doing what you did with the same WRX front calipers on the back, using the DBA rotors (want to keep Ebrake and I installed my 2003 center consul and would look weird with that missing) I was planning on using less aggressive pads on the back so the front would lock up slightly first. For the brake balance I did not install the FFR supplier proportioning valves, my thinking was the ABS will do that for me and at the time would save me on the time to add extra piping and bends to have them where they are easily assessable.Do you feel it would be a good idea to put them in as I have to disconnect some items anyways.

[Bob_n_Cincy]

Got it on the brake line orientation. It looks like I have them backwards, as I have the RR and FR going to the drivers side and RL & FL going to the passenger side. I will switch them over on my next days off. There goes my nice bends and bleed the system for like the hundredth time. For a long time my brake pedal would be nice a firm when bled and then would slowly get soft, same when driving, I could pump it up and then is would slowly go to the floor. I eventually changed out the master cylinder (not fun with windshield on and car mostly finished). It did not solve the issue. It is a bummer when the problem is smaller than that after you go through all that work. What had happened was when I painted the calipers I got some paint where the copper washers / banjo fittings go for the brakes, so it was not getting a good seal. I also switch out the pads to the EBC yellow stuff and made a big difference. The next thing I am working on is doing what you did with the same WRX front calipers on the back, using the DBA rotors (want to keep Ebrake and I installed my 2003 center consul and would look weird with that missing) I was planning on using less aggressive pads on the back so the front would lock up slightly first. For the brake balance I did not install the FFR supplier proportioning valves, my thinking was the ABS will do that for me and at the time would save me on the time to add extra piping and bends to have them where they are easily assessable.Do you feel it would be a good idea to put them in as I have to disconnect some items anyways.

If you are going to put big calipers in the rear, you do not need the proportioning valve.
There is a way to fix your abs without redoing your brake lines. It involves re-pinning your ABS connector.
Example: move RF sensor to LF connection point on abs module.
A lot easier than plumbing and bleeding.
Bob

[Chef818]

My electrical diagram does not go into detail of the connector, so much comes up, where can I find the schematic?

[Bob_n_Cincy]

My electrical diagram does not go into detail of the connector, so much comes up, where can I find the schematic?

Here is the ABS sensor diagram.

abs2.jpg


I don't have a schematic for an 03. Here is an O2.
https://1drv.ms/b/s!AgduxxAs3q-xg3pP...j2ZN7?e=VTrId6

[Chef818]

I was totally overthinking it and trying to find a schematic That showed all the ABS pump wiring, such as the one attached, not realizing that it just be-repining the sensors. Thanks for your help. I hope this solves it. Won’t be until Tuesday or Wednesday next week I get to itDB5D0859-AEB4-484E-8F65-F35DECD1B45B.png

[Chef818]

Been a while, but it is up and running like it is intended too. I did not have luck with re-pinning so I move the lines, had to re-bleed anyways with the new calipers, thanks for the help