brakes catching and locking up when going downhill and throttle body replacement

IndieDippy

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its likely something super simple and can be done at a local shop for cheap but i'd like it if any of you guys can give me a clue first. i daily my car and lately when driving down the hill i live atop when hitting the brakes at the bottom they seem to get stuck a bit. i've had it to where the wheels locked up too when hitting the brakes making a loud "skuuuurt" waking up the neighbors. need new brake pads you think? the brake pedal also seems kinda heavy these days too. another thing i wanna address about my 88 Gran fury is its ever present "clicking" noise. i've been told this is to do with a vacuum leak which the local mechanics seem to be unable to find. i've recently been told i need to replace my throttle body as it seems to be leaking oil and this may be the source of my vacuum leak. the engine bay seems a bit moist but i'm a little confused as the throttle body is connected to the carburetor. i just want to make sure these mechanics aren't trying to gyp me as i don't know a lot about how these old cars run and the diagrams only sort of make sense so if anyone can make help me out on what this means and if this is easy for me myself to fix and what part to order please let me know. thanks
 

Mikes5thAve

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Is it front or rear brakes locking up? Rears will lock up and squeal tires easily if they are out of adjustment. They can do the same if the axle seals are contaminated with oil from an axle shaft seal leaking.

You need some better diagnostic for the rest. These cars don't have throttle body they're carbureted and they can't leak oil from that spot. The most common place around there for oil leaks is the valve cover gaskets. Not sure on the clicking. How loud is it? It sounds like you need to find a local mechanic who's more used to older cars.
 

69-

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That would be my advice as well. Those mechanics do not seem to be very knowledgeable about your ride.
Re clicking: is it road speed dependent or engine rpm dependent? Then you need to find out where exactly it comes from, but rpm/speed gives you some direction. I doubt a vacuum relevance of the clicking (but at least could be some vac valve [but I doubt that]). And even more an oil leak relevance for a vaccum loss. :)

And I fully agree to get a general idea about what could be before some mechanic tells you even more bullshit.
 

kkritsilas

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Just Ideas of where to start, from a beginner point of view (Me):

-See if the clicking is from the front disk brake pads. Some have little metal clips that click when they are are getting close to wearing out. May help with your grabby brake issue, although I suspect that you may not only be looking at new disk brake pads, but either new rotors or at least re-surfacing the existing rotors.

-Neither throttle bodies nor caburetors have oil going through them, or where they mount to the intake manifold. Your car has a carburetor, so whoever you were talking to is completely clueless, as they obviously don't know what a carburetor looks like, and also don't know that neither carburetors nor throttle bodies have oil running through them.
 

Aspen500

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I wonder if they said, or meant, intake manifold is leaking. Those can, and do, leak oil out the ends and can also leak air (vacuum) into the intake ports. Still, they obviously don't know older cars and that's understandable. You need to find a shop with some "experienced" tech's that have been in the business for 30 or 40 years. That's how the shop I work at ends up getting a lot of older vehicles. Three of us in the shop have been tech's since the late '70's and early '80's.

Do your brakes have a problem all the time or just for the first few stops in the morning? If it's humid or damp, the rotors and drum can get a coat of flash rust overnight and cause that. Some brake pads and shoes have a tendency to lock up very easily in damp weather as well. Usually most noticeable on rear drums. I think it's the composition of the lining material. Ford had a HUGE problem with that on F-150's and Ranger's back in the '90's. Slightest touch of the brake pedal and the rear wheels were locked. Different brake shoes with a different lining formula solved the problem. Or,,,,,,,,,,,,I may be totally off base and what you're describing is something different.
 

Camtron

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Hard to say without looking at it but, I’d start with making sure the rear brake shoes are in good condition and adjusted correctly. With the rear end up off the ground and the car in neutral, grab a rear wheel and spin it as hard as you can. It should only make 1.5 - 2 rotations before stopping.
For the throttle body, as others pointed out, we don’t have them on our cars. You’ll want to find a better mechanic. The clicking could be the PCV clattering away or even a lifter tick.
Since you say oil is present, get everything cleaned up under the hood and let the engine run or take it for a short drive and then look. That way you have a chance of spotting where it’s coming from.
If you know of a shop or can find one that specializes in older cars, it maybe worth spending the extra money to make sure the work gets done correctly.
I recently ran into a similar issue trying to get an alignment done. Ended up going to 5 different shops before, I found someone who had enough familiarity with the car to put it on his lift and take care of it for me.
 

Aspen500

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A way of finding an oil leak, aside from florescent dye in the oil and a UV light, is to clean and dry the engine good and then spray athlete's foot powder (of all things) on the suspect areas and drive the car. The powder will stick to the engine and help find the true source of the leak. Otherwise it's easy to mistake the source since the oil will travel, either by gravity or by airflow. Sounds strange but it really does work.
 

IndieDippy

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advice as well. Those mechanics do not seem to be very knowledgeable about your ride.
Re clicking: is it road speed
sorry for late reply to you all. the clicking noise from what i've been told has to do with the vacuum system and is a door in the firewall opening and closing. it hasn't been bad lately as it will do it a few times after starting and be fine after revving the engine but it can also get to the point where it clicks rapidly and the car shakes a bit. restarting the car or putting it in park and revving will make this go away. it ain't rod knock i know that and it isn't from the wheels. this propblem has been going on long before my current brakes issue
 

IndieDippy

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I wonder if they said, or meant, intake manifold is leaking. Those can, and do, leak oil out the ends and can also leak air (vacuum) into the intake ports. Still, they obviously don't know older cars and that's understandable. You need to find a shop with some "experienced" tech's that have been in the business for 30 or 40 years. That's how the shop I work at ends up getting a lot of older vehicles. Three of us in the shop have been tech's since the late '70's and early '80's.

Do your brakes have a problem all the time or just for the first few stops in the morning? If it's humid or damp, the rotors and drum can get a coat of flash rust overnight and cause that. Some brake pads and shoes have a tendency to lock up very easily in damp weather as well. Usually most noticeable on rear drums. I think it's the composition of the lining material. Ford had a HUGE problem with that on F-150's and Ranger's back in the '90's. Slightest touch of the brake pedal and the rear wheels were locked. Different brake shoes with a different lining formula solved the problem. Or,,,,,,,,,,,,I may be totally off base and what you're describing is something different.
usually the first stop of the day. did it in hot weather in the early afternoon. i live a top a hill that isn't particularly steep but is still a hill none the less. car gets to rolling and up to about 20 mph. broke and was slowing down normal then SKUUURT. seemed to be from the front but i'm not 100% sure. i'll have a mechanic look at it sometime. i usually take her to the local Mr Tire branch and the guys are nice and give me good prices but they haven't been able to solve my constant "vacuum" issue and of course they're the ones telling me about how i need a throttle body replacement. the guy says he even used to work on Fleet Diplomats back in the day. i do think they meant intake manifold or valve cover gasket and had just been working on newer cars for so long they just slipped up. this shop does have many older cars at it though but at the end of the day is still a corporate shop that specializes in tires
 

IndieDippy

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after all this i really think my problem has just been me pressing down too hard on the pedal as i can't feel the pedal as good when wearing big boots. that and the pedal feeling kinda heavy at times
 

AJ/FormS

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Gran fury is its ever present "clicking" noise.
I think,
that clicking might be the electric gear box that adjusts your plenum door on top of the heater box that you can just barely remove if you have small hands. It has plastic gears and a torque switch that is supposed to turn it off when it hits the end of it's travel. But after the gears strip, the switch doesn't know where the door is.
When it is working right, it resets itself every time you turn the car off, and you can hear it whirrrrrrr and then stop. The next time you turn the key on, that thing adjusts the mixing door to whatever the A/C computer is programmed to tell it. Then after a while, as the air sampler senses the interior temp, it adjusts the door to achieve whatever you have set it too.
I gotta tell ya, this thing is a royal PITA to remove and a bigger one to install. At shop-rate, it will cost you several hundred dollars, to have it replaced.

Since the A/C computer doesn't know where the door is; when this happened to my Dad's car, the A/C didn't work right. I inherited that car when Pops died, and dug into it.

The clicking was the pinion gear continuously slapping the stripped teeth. It was winter, so I set it to heat, and unplugged the motor.
 

Aspen500

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The exact same thing happens to the electric HVAC actuators today. The gears strip and then CLICK CLICK CLICK CLICK.............and are just as hard, or MUCH harder, to change. Some you have to pull the instrument panel AND the HVAC plenum and possibly even disassemble the plenum all to remove 3 screws and change a darn actuator. I love my job, I love my job..... :cool:
 

BudW

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BUT - at least you can obtain actuator for today's cars. I hadn't seen a new HVAC actuator (for our cars) sense the mid '90's.
 

IndieDippy

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I think,
that clicking might be the electric gear box that adjusts your plenum door on top of the heater box that you can just barely remove if you have small hands. It has plastic gears and a torque switch that is supposed to turn it off when it hits the end of it's travel. But after the gears strip, the switch doesn't know where the door is.
When it is working right, it resets itself every time you turn the car off, and you can hear it whirrrrrrr and then stop. The next time you turn the key on, that thing adjusts the mixing door to whatever the A/C computer is programmed to tell it. Then after a while, as the air sampler senses the interior temp, it adjusts the door to achieve whatever you have set it too.
I gotta tell ya, this thing is a royal PITA to remove and a bigger one to install. At shop-rate, it will cost you several hundred dollars, to have it replaced.

Since the A/C computer doesn't know where the door is; when this happened to my Dad's car, the A/C didn't work right. I inherited that car when Pops died, and dug into it.

The clicking was the pinion gear continuously slapping the stripped teeth. It was winter, so I set it to heat, and unplugged the motor.
i have been told the sound is from somewhere in the firewall it MIGHT be this. thing is my car will jolt a pit when the clicking is heard and i've been told a bunch about my "vacuum leak" granted my car wasn't optioned with AC but the heater hoses were everywhere when i got it like on oh so many of these cars. i was able to put these all together with masking tape and get the blower motor replaced so i won't go another winter without heat for the time being. that said it only blows on the windshield and not out the vents. oh well, still warms the interior
 

BudW

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Refer to this thread for more about what I think might be your issue: Front Vents not working .

If your car came from factory without A/C then the vacuum lines will be a tad different – but most of what is in this thread will help you.
BudW

PS: Attaching pictures of your car, underhood and under dash, can help me see if I see anything that might be off. I have a good eye for that.

Edit: no/AC cars will not have the hot water valve. Hot water goes through the heater core 100% of the time. The manually controlled heater control head lever moves an air door (via cable) that allows a controlled amount of outside air to go past the heater core (varing between 0 to 100%), controlling the air temp you feel.
 
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IndieDippy

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welp, ended up finding out it was a leaking caliper. after a pricey repair now my brakes seem to be working too well. brake pedal all stiff but it works. anyways i'm off to try and find vacuum leaks.
Refer to this thread for more about what I think might be your issue: Front Vents not working .

If your car came from factory without A/C then the vacuum lines will be a tad different – but most of what is in this thread will help you.
BudW

PS: Attaching pictures of your car, underhood and under dash, can help me see if I see anything that might be off. I have a good eye for that.

Edit: no/AC cars will not have the hot water valve. Hot water goes through the heater core 100% of the time. The manually controlled heater control head lever moves an air door (via cable) that allows a controlled amount of outside air to go past the heater core (varing between 0 to 100%), controlling the air temp you feel.
I'll definitely try and get you some pics from around the Carb. unfortunately i'm none too experienced in mechanical work and most shops around my area don't seem to work on carbs anymore
 

Ele115

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Just show some of these kids a distributor and watch the fun begin. If they can't hook to it via bluetooth, they won't touch your car unless you throw some unGodly ammount their way, and it won't end well
 

IndieDippy

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i really wish it was simple enough for me to do this work from watching a youtube video but truly i need hands on experience, if i didn't need my car to get to work everyday i might start taking stuff apart and try this work myself but i'm too afraid of braking something. my main goal some point in the future is retrofitting a thermoquad. for not imma see if i can find a shop with some older guys who know how to rebuild my vacuum leaking 6280. i dunno, how much work needs to be done to slap a quadrajet on the civ spec 318? i'm guessing such a thing also involves a lean burn delete or isn't there a version from the cop cars that work with it?
 

BudW

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The Computers used on FMJ's are not as fancy as ones used today. They are also not as easy to diagnosis as well - sense you can't talk to them, like you can with today's automotive computers.

All of the FMJ computers automatically the ignition timing - which is a good thing.
The newer FMJ computers also control the carburetor fueling ratio (somewhat) - which is mostly independent from the ignition timing control.
Part of computer controlled carburetor problem is the range of computer control - which came about before Ethanol came out. Depending on the alcohol to gasoline ratio (which varies) can be about 10-15% alcohol to 85-90% gasoline. The non-computer controlled carburetors, like my '77 wagon, has no mechanism to cope with Ethanol and runs bad with it. It feels like my 132 HP drops down to maybe 100 HP. It is noticeable, but mostly because the car has no way to cope - without changing the jets for the increased fuel needs.
The Chrysler computer controlled carburetors have some flexibility and can alter the fuel needs up about 5% or down about 5% (about a 10% swing, total) - which is just not enough for the increased fuel need for running the increased fuel need that Ethanol requires. That said, both of the FMJ versions (non or computer controlled carburetors) will run on either 100% gasoline or Ethanol, but neither very well. The computer controlled version a bit better than the other, but not but much better.

Getting back to my point, my '86 Fifth Ave (318 2-bbl) originally came with a Holley 6280 (the computer controlled version of the Holley 2280). It has been replaced with a Chinese knockoff Carter BBD and it works wonderful. The Lean Burn computer is controlling the ignition system just fine and it also "thinks" it is controlling the carburetor as well - but it is not.

Now getting back to your situation, You can change out the existing carburetor with a non-computer controlled version (Carter BBD, Holley 2280, or even any version of a 4-bbl) and leave the existing ignition system in-place and it will get along fine (providing one is not breaking any state or local laws by doing such). Changing the ignition system to a more simple changeover will work as well, but to be honest with you, a properly working computer will work so much better (in all situations) than the simple ignition system will - except until engine reaches "operating temperature". Then Lean Burn senses engine is "cold", it reduces the engine power level down by adjusting the ignition timing down, until it gets warm - which is also a great idea. An irritating thing, but it is best for the engine.

The only thing different about police vs. non-police car computers was the computer moved from the air cleaner to down by the parking brake petal under the dash. The computer programing is not any different between the two versions (or if it is, it is very minor). All in all, computers (in general) don't like water moisture, heat and vibration - so by having it mounted on the air cleaner, above the exhaust manifold, you have the heat, the vibration and to some extent, water moisture, all there. That said, the Chrysler computers used for FMJ's had very little problems, for the most part. About 95% of all Lean Burn computer problems were not even computer (or computer sensor) related. That 95% pointed to other things (like loose timing chain, faulty spark plug wire, stopped-up catalytic converter, and so forth).
Actually, I think the 95% number might be closer to maybe 99% (being problems were elsewhere).

Now the computer system used for today's are a lot more problematic - and mostly with sensors more than anything else.
BudW
 

IndieDippy

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will the part of the 6280 with the plug need to be retrofitted on a new carb or that can be removed and it'll just make it so the computer only controls fuel ratio and senses engine temp? either way its possible i can rip a carb off a cop diplomat granted we ever decide to let go of the 83 AHB Dip we got.
 
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