1991 Crown Vic parking brake

I think the release is supposed to have vacuum while the trans is in any forward gear. So, if you put it in P, and the vacuum doesn't bleed off, it's the vacuum valve on the column. If you put it in P and the vacuum bleeds off but the release doesn't return, it's the release canister. Watch the canister when the trans is put in P and the engine is shut off. If the canister does not return, pull the vac line to see what it does.

 

That was my plan but thanks for the reminder anyway. It never hurts to assume I don't know what I'm doing.

 

Okay...started with the brake engaged. Started the car and shifted to OD and the brake released. Shifted back to park and turned engine off. The vacuum did not release and I could not engage the brake. Waited an hour and the vacuum had leaked down and the brake would engage again. Started the car again, shifted into OD, turned engine off and pulled the vacuum line. The vacuum released and the piston in the release canister returned to the home position.

That sounds like the vacuum valve on the column from your description. I can see the vacuum line going up over the steering column near the steering wheel. No way from the bottom to see where it goes after that or get to that area. Looks like the front panel on the dash will have to be removed to get to the vacuum valve from the top. I'm going to hold off on that for now since I will need to pull the dash panel off and probably remove the instrument cluster to replace the airbag warning light that the prior owner removed. I don't want to install that light until I can get the airbag module repaired/replaced...don't want the light flashing continuously...25 chimes every half hour is bad enough!

 

Okay, the part is in a big brown truck near my neighborhood. I've got the dash trim off and can see the part that needs to be replaced. I'm trying to get the instrument cluster out to be able to access the vacuum valve and am stumped on step 5 in the shop manual...posted above. Can anybody tell me what screw the manual is talking about. Pictures would be good if you can without dismantling your dash or a good verbal description. Thanks for any help you can offer.

 

While this isn't the same car, it's the universal way that the manufacturers did it for decades:



On the column near the shifter, you will see something like to the left of the big nut on the upper side of the dash. It's a metal wire with a screw that attaches to your column that rotates with the shifter.

 

Thanks, elB. Is the gold colored screw above and to the left of the black ribbed piece the one mentioned in step 5? The thin red wire goes up and loops over a stud on the shift mechanism. I think this is the cable loop mentioned in step 5.

 

That is it! It comes off the column as a unit. Here's a slightly later model Ford that uses the same steering column:



Here's it removed and dangling:

 

Thanks for the confirmation. When I was 16-17, I did not hesitate to take things apart. Now that I'm 70+, I have this nagging concern that I won't be able to get it back together or it won't work when I finish! I guess that's the results of screwing many things up over the years.

 

Like Hannibal used to say on the A Team...I love it when a plan comes together. Got the instrument cluster out, replaced the airbag light bulb (got to put some black tape over it until I get my airbag problem fixed) and replaced the vacuum valve for the parking brake release. Got the cluster back in and now have a blinking airbag light and the parking brake releases by vacuum. The end of the old fitting was noticeably worn which may have been what was causing the problem.

Now if I can get the airbag issue resolved without blowing the bag, I'll feel like a NASCAR crew chief.

Thanks for all the advice here. I'm sure I'll need more in the future.

 

That's why nearly all airbag physical work is done with the battery disconnected and a two-minute delay before doing any work. Diagnosis involving the airbag itself really only needs to be done by a factory-trained tech.

 

I've got a mechanic friend that used to work for Ford. I've talked to him about the issue and need to catch him again and get him to look things over. I'll post his work in my airbag thread.

 

Good to have friends like that. Buy him a half-rack, just because.

 

He has a young son and is building a house...he's going to want $ for his time/knowledge. Okay with me.

 

As it should be. I usually only did free work for my brother, who was also disabled.