dvandentop

well i finally got the vette out and fully charged last night went for a ride and the pedal was still feeling funny, this is after my front caliper cleaning and tear down. the pedal is rock hard but will lock up to abs almost instantaneous. so i went into a undeveloped area and with traction control off, (1 push, couldn't turn active handling all way off since didnt program tires) well the front left wheel locked up and would push the front tire if i kept driving would create a flat spot and not roll at all, liked a locked up wheel, so i stopped tried to take off again and still locked up. so i pressed real hard on brake pedal a few times then it freed up. i put in reverse for a few feet then drive. then it worked ok.

i headed straight home and tried not to use the brakes.


any suggestions? i thinking air in the lines still? the wheel locked up after i did a hard stop on the brakes to try to get the right pedal feel.


i am going to try another pressure bleed all the way around while letting the liquid gold (srf) flow out the bleeders. i did cycle abs mutiple times to try to get any trapped air out.

mgarfias

Did you pull DTC codes?

dvandentop

no codes such as ses light at all just glad i wasnt going any faster

BEZ06

Hey Derek

You say you had a solid pedal.

It sounds to me like maybe air in the ABS circuits in the lines to the BPMV. In that case you'd probably have a solid pedal until the ABS activated and the lines with air in them went into action.

If so, you'll need a Tech 2 to cycle those ABS valves during bleeding.

Bob

dvandentop

thanks bob that is what i have read from previous post i am i am going to try 1 more bleed to see what i can get out, otherwise going to try the tech 2 route, this srf is expensive to have to bleed out but what can ya do!

Bill Dearborn

Even with air in the BPMV the brake should not lock up. The unit would cycle as soon as the EBCM detected the wheel speed at that wheel going to zero. Any air in the unit might bleed out into the line and effectively further reduce brake pressure. You may have air in the unit but I suspect you have some other more direct issue. Something is causing the caliper to lock the wheel and that means there is a mechanical problem out at the caliper doing something. I am not sure what the EBCM would do if the ABS couldn't release the caliper. It might throw a code but you didn't mention seeing the ABS light on the I/P.

Bill

UstaB-GS549

Check the hose?

I have seen OEM type hoses work like a one way check valve.

Jason

Happened on my wife's truck. Junk in the line.

dvandentop

thanks for suggestions i will check that out

John Shiels

bad booster will give you a hard high pedal in many vehicles or as stated above brake lines can collapse creating a one-way valve but the brakes usually work they just don't release.

Everett Ogilvie

Sounds mechanical to me. In the caliper. Piston cocked in bore, or something similar.

John Shiels

didn't you have all the crap in the lines? You may have contaminated the system?

dvandentop

yeah i had a bunch of crap in the actual calipers, maybe there is a bunch of crap in the lines too, gonna take those off and those out

95jersey

I had an ABS sensor go bad on my C6Z and it did EXACTLY what you are talking about. (mine was in the rear). I got the dealer to replace the sensor under warranty and it fixed the issue.

froggy47

I also vote mechanical, rather than air in lines (or both).

Everett Ogilvie

I bet you will find a piece of debris (crap) in between a piston and the bore.....

John Shiels

could it be deeper in the system beyond the lines?

UstaB-GS549

Wheel off
Lug nuts on backwards to hold rotor against hub.
Start engine & apply brakes.
Engine off. Did caliper release?
If not crack line at frame. Did caliper release?
If not crack line at caliper. Did caliper release?
If not piston jammed in bore.

This might help isolate where the problem is. Good luck.

dvandentop

thanks will try that as well, as for the piston jammed in the bore what could cause that??

John Shiels

metal shavings you had. I had a rough terrain forklift (Lull) and I could not diagnose hydraulic functions that wouldn't work. Few minute pieces of metal in a few places. 3+ weeks and 10 grand later it was fixed. Dealer was going nuts to find out what was wrong going back and forth with the factory.