1998 V70 AWD Turbo Cross country. There are a few braking problems that might be linked together.
The brakes are hard to push,, very hard and hard to stop. The ABS & TRAC lights come on at random. The engine light is on also,, code reads Vacuum leak and MAP or MASS problem.
So I did a test on the Brake Booster. Pump the brakes and hold with the engine off, then hold the brakes and start it. The brakes go down after the engine starts which tells me the booster is fine.
I checked all the vacuum lines I could find and they all looked great.
I have done a brake/rotor change on the front and the brakes are still hard to push.

I have read that the brakes should work fine without the ABS module/pump working.
So what do you thinkis my problem?

Could the ABS pump be the problem?

Any help would be greatly appreciated,,, Thanks

 

I think the ABS light is coming on due to the module bad.
I still don't know why the brakes are HARD,, like manual brakes on my old 66 Chevelle.

Any body?

 

It definitely sounds to me like a hydraulic problem. Hard to stop = little contact between rotor and brake pads. Little contact would probably be caused by really worn pads or low hydraulic pressure. When combined with the "hard to push" pedal, I'd say it sounds like you have too much pressure built up near the pedal and not enough at the brakes. I'm not sure how the system is set up, but this would seem to make more sense if it is set up as a "dual-circuit hydraulic" where the hydraulic pressure from your brake pedal is read by a computer which says how much pressure to send to the actual brakes. In that case, I'd check out the sensor that measures the pressure.

Again, I'm no expert, I'm just trying to take a guess that might give yousomething to check.

***EDIT*** Now that I think about it - I guess that sensor is probably the ABS control module, so it could be related.

Can anyone provide a better answer to this?

 

Thanks for helping 99VolvoV70,,, I have read a few pages that say the brakes should work fine without the module, tho the ABS won't. What you say makes good since tho.
I just did a front brake job and I bleed allfour brakes with my one man bleeding system. My point all the calipers shot brake fluid out with a lot of pressure,,, tho this doesn't mean the calipers aren't locked up somewhere. I know the front works great.I would swear it was the booster,, but....

 

Could thecheck valve be the culprit. That is what someone else has told me. Does it at like a PVC valve?

 

I'm not sure what that does, but here's a picture of it: http://www.eeuroparts.com/productdet...&code=9391

 

That is either a bad booster or valve.
If you pull the valve out of the booster with the car running and have vaccum at the valve it is good.
No vaccum the valve is bad.

For the ABS and Trac's light most likely a bad ABS module.

 

I really got down on the brakes today,, I mean really hard going 25, 35 and 45mph. The brake pedal is hard but it stopped on a dime. As for as normal stopping you really have to press it, but if you want to stop on a dime,, it will with alot of force.
We have two V70s. The AWD turbo and FWD non-Turbo. The FWD V70 brakes are great and easy to use.
Is the AWD harder to stop due to the add weight and momentum?

 

This will help you brake.
I think you could use this.
please click here.
http://www.ipdusa.com/Volvo-SV70-199...p-128-361-297/
has new brake lines and everything but the
ABS and tracs mod.

 

I have had problems with the two lights befor.
I used a new module.
check this price.
http://shop.voparts.com/brand.php?ma..._unit&my=1
You could also get a rebuilt units for less but i would not trust any.
The seals like to go bad due to the heat, and the loaction to the modules is on theright side of the enigne.
Do you drive in hot weather ?

 

Check the break hoses and bleed breaks this sometimes this shows you if the caliper hose is giving you the issue.The other thing you can try is go some where very safe and really apply the breaks you should hear and feel the anti-lock (light needs to be off). Just be safe about the hard breaking. The other thing i have seen it that the wires going to the anti- lock modual had break fluidleft on them.. (39.99 Pad replacement gone realbad )The wires just melt away ,and the entire harness had to be replaced.