Problem:
About 5 months ago this vehical started to have a spongy brake pedal and loss of braking.The following work was done in order to try and correct this.
First the master cylinder brake fluid was checked and there was no real loss of fluid.
There were no visual signs of brake fluid leaks.
The brake system was bled and the brake performance was restored.
It ran about 3-4 weeks and the brake pedal became spongy again.The brake system was again bled and performance restored.This work was done by the used car dealer who the car was bought from.
It ran again for several weeks and this spongy pedal reoccurred again.The dealer tried to tell me that it was probably just trapped air in the system that had to work its way out.I didn’t buy this and decided to look at this myself.I am a diesel engine tech and have some car experience.
When I looked at it I noticed that when bleeding the brakes that the left front caliper was the only one with air in it.After bleeding the air the brake performance was again OK.
Being concerned as to why the air was just coming from the left front caliper I decided to look closely at the caliper.Didn’t see any signs of brake fluid around the seal and the piston seem to move in and out OK.
Just to eliminate any possibility that the caliper was causing this I replaced the caliper.
The van ran about 2-3 weeks and again got the spongy brake pedal and loss of braking.Rechecking there were no brake fluid loss or signs of leaks.
Rechecking when bleeding the brakes found air again only at the left front caliper.
Just as a hunch decided to replace the master cylinder.
The van ran about (4) weeks and the same scenario again.Still air at the left front wheel and no fluid loss.
I have been bleeding the brakes (just the left front) now for several months every few weeks just to be able to keep using it although it seems to be getting more frequent now.
Conclusions:
Can you offer any advised I am at wits end?I tried calling Chrysler for technical assistance but really didn’t get much help.I was thinking about a possible ABS problems and if there would be anyway this could introduce any air into the brake system?Any advise would be greatly appreciated.