96 4-Runner Funny noise

[CruisinMT]

96' 4 runner, stock v-6, standard tranny

Hey guys I'm getting a funny noise out of something in my engine bay. Passenger side near the firewall it has 5 hoses coming out of it. Some sort of pump? what is it and why is it making that noise?

 

[CruisinMT]

this is what I'm talking about. this is a photo off the web.

 

[raydouble]

If I'm not mistaken that is your abs module, 5 hard lines right?

When is the noise occurring?
During braking? All the time?
ABS light on?

 

[CruisinMT]

yeah there are 5 hard lines. I didnt notice the ABS light being on when I was checking it over last night. After the engine has warmed up, it makes the noise after I shut it down and turn the key to the on position just before it cranks over. and randomly when in motion. has not made the noise yet today though. weird.

 

[raydouble]

yeah there are 5 hard lines. I didnt notice the ABS light being on when I was checking it over last night. After the engine has warmed up, it makes the noise after I shut it down and turn the key to the on position just before it cranks over. and randomly when in motion. has not made the noise yet today though. weird.

That actually is exactly how the newer (00-02) abs systems work the motor keeps the hydraulic boost pressure up.
Is it a new noise or did it just start?

Also check your owners manual on the abs operation, might be completely normal......available here if you don't have one.
https://forum.ih8mud.com/95-gen-toyota-trucks/341631-3rd-gen-4runner-faqs.html

 

[CruisinMT]

We just got back from a 2000 miles trip and didnt hear it at all while on the road. Seems to have just started yesterday. I'll check out the FAQ and maybe it will answer my question.

 

[raydouble]

We just got back from a 2000 miles trip and didnt hear it at all while on the road. Seems to have just started yesterday. I'll check out the FAQ and maybe it will answer my question.

More than likely not, unless it's in the owners manual.

I'm not real familar with that abs system.....could be the same as the late 90's Tacomas, you might be able to look though the FSM here and get some more info.
Toyota Tacoma/ 4Runner/ Tundra/ FJ Cruiser Factory Service Manual Page

 

[CruisinMT]

whats the worst case scenario with this thing if it goes out? COuld it be telling me i have a leak in my brakes somewhere so it needs to repressurize the system?

 

[raydouble]

whats the worst case scenario with this thing if it goes out? COuld it be telling me i have a leak in my brakes somewhere so it needs to repressurize the system?

Worst case is having to replace either the unit or the ecu that controls it.

Wouldn't think so, but how is your fluid level looking? It looked full (but dirty) in the pic you posted, but I don't know when it was taken.
I think your emergency brake light would come on before the fluid ran low enough to cause the abs to malfunction.

 

[CruisinMT]

thats not a picture of my engine bay just an example to show what I was talking about. I havent gotten any warning lights on the dash yet. I will look over the fluid etc. tonight after work. So if it went out it would just cause me to have regular disc brakes without ABS correct?

 

[raydouble]

thats not a picture of my engine bay just an example to show what I was talking about. I havent gotten any warning lights on the dash yet. I will look over the fluid etc. tonight after work. So if it went out it would just cause me to have regular disc brakes without ABS correct?

I believe so. I'd read that manual and looks for leaks.

 

[CruisinMT]

I'll give another look tonight and if I can't find anything I'll just run it till it goes. one more question, how often should the brakes themselves be checked?

 

[raydouble]

I'll give another look tonight and if I can't find anything I'll just run it till it goes. one more question, how often should the brakes themselves be checked?

I usually do a quick check everytime I've got the wheel off....but I'd say every three to six months or so.
How many miles does it have on it?

I don't think there is anyway worn out brake pads or shoes would cause the issue you are having.

 

[CruisinMT]

140K on the rig now. not sure when the brakes were done last. I'll inspect them this weekend.

 

[raydouble]

I took the liberty of copying this out of the manual, for you and future viewers.

ABS section

 

[CruisinMT]

so it is just in self check mode. strange I never heard it do that before. Good to know I'm not in any immediate danger should the ABS system fail. Thanks Ray you tha man!

 

[raydouble]

so it is just in self check mode. strange I never heard it do that before. Good to know I'm not in any immediate danger should the ABS system fail. Thanks Ray you tha man!

Yeah, I guess if the lights not on and you don't feel any weirdness in the pedal or braking, you should be good.

Not a bad idea to inspect the pads/shoes and system though.

 

[Duane]

For what it's worth I notice my 96 makes odd noises after I shut it off which I have always considered it doing something with the ABS.
Don't know that I have ever noticed much noise when starting the 96 or either 99.
As for lining wear... I haven't changed any as of yet front or back. When I bought all 3 of mine I usually knock the rims off and inspect the rotors and drums, spin them to see if the wheel bearings feel good, look for leaks in brake cylinders or calipers, check out the hardware and look at the amount of brake lining left.
I am pretty impressed with how long the linings last..I sort of doubt I will ever replace the rear shoes and just front pads in time.
I keep an eye on the brake reservoir levels and should likely look at the rear more often but do look at the front pads when rotating tires or swapping rims over.

 

[4runner4ever]

4runner frog

Both 4runners I have owned make that noise-the '00 not as bad as the '96. Sounds like there is a frog under the hood after it is shut down.