[BrushApe]

I have a 97 Ford super cab with a 7.3 liter diesel. Brake light kept coming on which would kick me off cruise, (the only way to fly). Anyways, took it to the shop and after scratching their heads some they threw a new vacum pump at the problem, ($300+). Drove to town and light came back on, back to shop, threw a new master cylinder at it, cost only-no labor, another $80+. Drove it for three days no problemo. Paid for new master cylinder Monday and off on my merry way. Drove to Pendleton for work today, on way back, light is back on. Brake pedal feels hard, pump multiple times and light goes out, then few seconds later back on. Repeat multiple times then E brake test, no change. Finally pump the tar out of the pedal and light went off and stayed off.assout:

Any of you geniuses out there have any ideas!!!!!!!!!!!!!!!

Thanks for any help, tired of throwing parts at it, could be buying fishing toys!!!!!!!!!!!!


BA

 

[MattPark]

Is the brake pedal hard all the time? Sure sounds like the vacuum pump is gone, or there's a leak in the line. If you can pull the line off the brake booster while the engine is running, that will tell you if the "new" vacuum pump is working. Also could be that hose that's leaking.

Is the ABS light coming on as well? If so, check the ABS fuse. Could also be the stoplight switch under the pedal, or the ABS sensor on the rear axle, but neither of those should give you a hard pedal.

Stay away from places that "throw" parts at problems, instead of diagnosing what's actually wrong. If they can't figure out what's wrong, they don't need to be working on your vehicle.

 

[Fishingfanatic]

Sounds to me like a low fluid light. Make sure the float on top of the brake fluid reservoir is not sticking in the down position.

 

[lundprov]

Does the abs light also flash at the same time ?

 

[1pump]

Might be the porportioning valve (if it has one).

 

[BrushApe]

The ABS light was one of the first questions the shop asked, no it does not come on at all. Brake is only hard when the light is on. Use to be only when traveling, now after the "repairs" seems to happen only after sitting for a bit. Monday AM got into the truck, light was on and brake pedal was hard, pumped it a few times hard and problem went away until this PM on way back from Pendleton and the truck having set for three hours. I asked the shop today if it could be just a hose with a leak and (main guy not there) they didn't think that would cause my problem. Fluid level is fine, will have to check out the stuck float suggestion. Can't figure out how it would get stuck down if fluid level remains up though. I fully admit I am a mechanical idiot so any ideas you guys come up with would be greatly appreciated. Like what is the porportioning valve, talking greek to me, does mine have it, not a clue, see what I mean, a real dumb dumb. Thanks BA

In defense of the shop, they did spend considerable time messing with the pump and the lines while the light was on and it seemed to be the vacum pump that was the issue. When that didn't work they didn't charge any labor for additional work with master cylinder. It is going to be something silly I am sure, it is just being a pain in the mean time.

 

[IDWITHELD]

I would check the e-brake switch and verify it is not jiggling, loose or broken.
On my 93gt I had a brake pedal switch break and it was rattling around. Me thinks this disables the cruise control...but am not sure.

 

[BrushApe]

They already eliminated E-brake as a cause, thanks!

 

[jvp]

last time i had a similar problem the spring that held the brake pedal up was weak so added another i had around a that took care of it. probably not it but you could check it easy enough:shrug:

tbird shuts off cuise when i put on the right turn signal but only occasionally since i put in a new turn signal/and more assembly

 

[BrushApe]

jvp- been there and done that, checked that to, my old Ford half ton from college used to do that, just hooked my toe under pedal to make like go off. Not the issue here but thanks.
BA

 

[bait dunker]

i suggest you take your ford to the dealer for the recalls and updates. there is a recall for the cruise control, i have seen this same problem twice, minus the hard brake pedal. i think the cruise control recall should take care of most of your problem!

 

[huntercgr]

I have a 97 Ford super cab with a 7.3 liter diesel

Recall for a '97 cruise control? Hmmmmm.......:shocked:

 

[BrushApe]

Yes there was a recall but not for my 97, unless I missed something. It was a different year. And how would that explain the light coming on and the hard pedal when cruise not activated:shrug:. Thanks for thinking guys, there has to be a reason. Came on Tuesday PM as stated before, hasn't came on since, go figure :shrug::shrug:. Heading for antelope camp in AM, will see how it does this week.

BA