Hi guys.
I have an 06 TJ and need confirmation if my troubleshooting steps and conclusion below are correct and advice on some brands of replacement parts if it is!
I recently got a P0507 code out of nowhere. Engine was idling slightly higher than normal. Fluctuates between 750 and 1k throughout the day. Nothing major though.
I did the IAC clean with TB cleaner, TPS and MAF are fairly new, checked for vacuum leaks, couldn't find anything until I reached the brake booster. Turns out there's a big brake oil leak at the mating point of the master cylinder and booster. It kind of circulates both above and below the mating point. Photo attached.
I also noticed the bushes under the brake oil canister were wet and the cylinder was wet at the bottom.
Other clear symptoms:
- the idle rpm rises when I press the brake, significantly when I press multiple times.
- I plugged the vacuum output for the brake booster and compared engine idle rpm between plugged and unplugged. Difference isn't huge (photos attached below) but with the rest of the evidence it's enough to confirm to me that the booster failed or is on its way.
Booster connected
Booster disconnected and vacuum plugged
Weird thing is the P0507 disappeared yesterday while driving, but I figure it will come back and it's just because the booster still hasn't checked out fully.
My brakes still feel fine but I don't know how long that will last.
With all the above, I decided it's safe to change both booster and master cylinder. I would appreciate your help on advising me what brands to go with since Mopar discontinued both. So far I'm leaning towards Crown.
Secondly, if you think I missed something with the above troubleshooting, please do let me know!
Thanks, Yaseen.
I have an 06 TJ and need confirmation if my troubleshooting steps and conclusion below are correct and advice on some brands of replacement parts if it is!
I recently got a P0507 code out of nowhere. Engine was idling slightly higher than normal. Fluctuates between 750 and 1k throughout the day. Nothing major though.
I did the IAC clean with TB cleaner, TPS and MAF are fairly new, checked for vacuum leaks, couldn't find anything until I reached the brake booster. Turns out there's a big brake oil leak at the mating point of the master cylinder and booster. It kind of circulates both above and below the mating point. Photo attached.
I also noticed the bushes under the brake oil canister were wet and the cylinder was wet at the bottom.
Other clear symptoms:
- the idle rpm rises when I press the brake, significantly when I press multiple times.
- I plugged the vacuum output for the brake booster and compared engine idle rpm between plugged and unplugged. Difference isn't huge (photos attached below) but with the rest of the evidence it's enough to confirm to me that the booster failed or is on its way.
Booster connected
Booster disconnected and vacuum plugged
Weird thing is the P0507 disappeared yesterday while driving, but I figure it will come back and it's just because the booster still hasn't checked out fully.
My brakes still feel fine but I don't know how long that will last.
With all the above, I decided it's safe to change both booster and master cylinder. I would appreciate your help on advising me what brands to go with since Mopar discontinued both. So far I'm leaning towards Crown.
Secondly, if you think I missed something with the above troubleshooting, please do let me know!
Thanks, Yaseen.
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