CarTalk.com Best of Deals Car Reviews Repair Shops Cars A-Z Radio Show

ABS brake fluid modulator valve for Chevy Corvette

Dear Tom and Ray - I’ve got a 2002 Corvette with about 155K miles on it and the Check Active Handling light has been on and off intermittently for a while. So I took it to the mechanic who ran the codes and said I needed the captioned valve. Bad news was, the part cost $2100!! I reminded him that this was not the Space Shuttle but he confirmed that was what Chevy charged. I asked him to look into getting one in the “after market” (i.e., junkyard). He hasn’t found one. Not sure how hard he is looking. This raises a few questions. First, can I get a serviceable used valve ? Second (maybe first) is it dangerous for me to drive the car in its current condition? And finally (but maybe most importantly) are all the routine Corvette replacement parts priced by Tiffany’s? Should I get rid of this thing before I need to mortgage my house to buy an oil pump?

Makes you wonder how GM can afford to sell a car for $50,000 when it has a half million dollars worth of parts in it.

I’m unfamiliar with the term “captioned valve”, and was unable to find a reference to one on Google. But I can tell you that an ABS modulator sftermarket for your car is a grand and the modulator isn’t designed to allow the valves to be changed individually.

http://www.buyautoparts.com/buynow/2002/Chevrolet/Corvette/ABS_Control_Module/74-00030_ON.html

It appears that the electronic brake unit comes in two parts. The module that “the same mountainbike” mentions is the Electronic Brake Control Module. There is a separate hydrualic module that has the solenoid armatures, valving; pump; and motor.

So far I haven’t found a part listing or price for the Brake Pressure Modulator Valve unit. One of the reasons this unit may not be available in the used market is that it is the most likely part of the electronic brake system to fail i.e. corrosion or debris is most likely to jamb the valving or cause the seating to be imcompetent. Even if you found a replacement BPMV unit, it too might have problems. As “the same mountainbike” said, the BPMV unit does not allow for individual valve replacement.

As to the cost of this unit, it is no surprise that it is so high. It not only provides ABS function but can individually apply calipers to provide traction control; modulate vehicle yaw; control understeer or oversteer; supply digital proportioning; and control lateral acceleration. This is quite a list of capabilities. Sort of takes all the fun out of driving a high performance car i.e. keeping it on the edge.

You might check around for any rebuild firms that will rebuild your unit. The core charge on a replacement unit is rather high so I assume that either the manfacturer or other firms can rebuild dead units. I once had the chance to experiment on an ABS unit but the core charge was $300 so I let the opportunity pass.

Hope this helps.

1998 Range Rover in my drive. Great vehicle, but a “high performance” vehicle. Brake pump controls ABS, Traction Control, Stability. Also has brake fluid pressure tank. $1360. Many newer “upscale” vehicles are getting this kind of setup.

Les