How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Matt Your Own Question
Matt
Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22176
Experience:  BEng hons Mech engineering, in auto industry 22 years
12772297
Type Your Car Question Here...
Matt is online now

I have replaced the front calipers on my nissan xtrail T30

Resolved Question:

I have replaced the front calipers on my nissan xtrail T30 2007 & bled the brakes in sequence (Rear right brake→Front left brake→Rear left brake→Front right brake) but still have air in the system, do I need to bleed the ABS unit as well if so how is done. If this is not the problem what is the best way to remove the airlock any advice would be much appreciated.
Thanks Paul
Submitted: 1 month ago.
Category: Car
Expert:  Matt replied 1 month ago.

Hello

as you've bled all corners then it could be a flexible brake line is ballooning under pressure, this can't always be seen from the outside so to test this use a hose clamp on each line in turn to close off then lines one at time . Push the pedal in between and see if you can feel any difference as each line is closed off.

if this doesn't help then its possible that you need to run the ABS pump to move any trapped air inside
the dealer method is to use the diagnostic tool to cycle the ABS during bleeding

however I've had good results buy just taking the car for short drive and stamping on the pedal at low speed to lock the brakes and trigger the ABS
and then re-bleed

Matt and other Car Specialists are ready to help you