The LF brake caliper on my 90 vert has been sticking for months now.
I replaced the caliper, brake hose, flushed the system with fresh fluid and it still hangs a bit. It doesn't pull but after a few miles when you come to a stop you can smell the pad. I have read many threads about this and I am mostly convinced the my ABS module/pump is sticking on the LF valve. Has anyone replaced their ABS unit with a pre-abs system OR know of anyone that rebuilds these ABS units? Spring is coming and I want to be able to take my vette on trips. It only has 54,000 miles on it. Other than this issue it is a great ride!!!
ANY suggestions are greatly appreciated. I live in Concord NC is anyone is close enough to help OR know of a good vette mechanic in and around this area.. thanks..Julian

 

..... Check the caliper pins that the caliper bolts to and make sure they are not corroded or dry ... they need to be lubed and free to move or the pads will drag ..... I doubt that the ABS is at fault .....

 

Just that hose or all of them? I'd put some good quality braided SS hose

I wouldn't replace it with a pre ABS unit. That is a very handy thing to have. https://www.google.com/search?source...7j0l5.5207j0j4

 

I've read some things on the abs. One is where something gets into it and plugs up one particular valve. I've read where some have tried reversing the flow with a pump and got it to clear. Another is to pull the pump and put in a proportioning valve in it's place.

I think I was on this forum I've read some threads on this so suggest doing a search on abs and see what comes up.

 

Take it to GM. They have a scanner that will pulse the ABS. It may clear the blockage or verify that the system is broken.

 

this is a serious problem that can kill you.

in 2000, car and driver editor got killed driving a modified mercedes slk roadster around a track.

he made a high speed stop before a corner. one caliper locked and the car went into a slide, rolling end over end when it went off the track.

it caught fire and burned with the editor trapped inside the burning wreckage.

there was a guy with a modfied viper there that was so disturbed he sold all of his racing cars....

get this fixed

 

thanks for the info..any idea what proportioning valve was used to by pass the pump? 85 or earlier ?? thanks again

 

Brakes aren't something you should bypass to cheap out fixing. I don't care if you ever drive again but I'd rather you be able to stop if you drive. It can be painful if you don't stop when you need to.

 

Take the car for a ride till the brakes get up to temp, jack up the corner that is getting hot, is it dragging? If so then open the bleeder, is it still dragging?

 

Good luck if you can find a dealership with the equipment to test or work on them, I couldn’t.
You really need to discuss this with someone knowledgeable on brakes to know what to do. Proportioning valves can be picked up via most automotive supply houses. Plumbing and adjusting can be done but remember some of the fittings are likely metric. It’s very similar to converting a car from drum brakes to disk. Getting it installed is the easy part once you have all the correct pieces for your install. It’s getting it all adjusted to work correctly. Maybe talk to places like Wilwood for their recommendations.
This is not talking about bypassing the brakes, only the ABS if needed. It is taking out the brake pulsing on slippery conditions. Long before ABS, people had to do this themselves. A defective ABS can be more dangerous than not having it at all.

On a side note, I thought I might have a problem with my ABS unit in my 86 at one time. I was unsuccessful in finding anyone that was able to test let alone repair the Bosch ABS used at that time. If anyone does turn up a place, I’m sure there are a lot of people that would like to know who and where. The only option I've ever found for the unit repair or the sensors is to find used units and that's iffy as you don't know if the replacements are any better than what you're replacing.

 

I wanna say I did get it done a few years ago. Can't remember the place though. I haven't got air in it where I had to bleed YET. The day is young.

Yes, I'd say I'd talk to them and see if they sell a kit for ease. No fun running down chasing parts and having to order them and wait while everything is apart because you didn't think of that one item.

Here is the problem I see. All my cars are ABS so I am used to standing on them and letting the ABS do the job. In the old days, you had to pulse. Whether you can remember to do it or will muscle memory kick in and you stand on it is another story. A slippery condition isn't something you want to experiment with. Pulsing when you don't have to might not be a good idea and not pulsing when you should, well......