2008 4Runner V6 Sport - 98,000 miles - Well maintained

Before handing over $3000 to the dealership to "fix" this problem, I thought I would come here for some advice.

While the engine is running, every 6 seconds the accumulator fills for 1-2 seconds, follwed by a brief "squelch" from what sounds like near the master cylinder solenoid.

The dealership, basically, would like to replace everything (at my expense).

My questions are:

1) Are the 2 sounds related as they both started at the same time

2) Any way to repair individual components without purchasing entire assemblies.

Thank you for any assistance.

1. I don't know about the squelch sound, but if the pump is running every 6 seconds, something is wrong. I was working on the power steering today, and I only heard the pump run once or twice in an hour. It also runs when I start the engine, and now it has started running again shortly after that for some reason. It also runs about every other time I press the brakes. If you don't fix it, you might burn out the motor or have compromised braking.

2. Not really, as far as I know. @BlackWorksInc might be able to tell you more.

Every 6 seconds is too quick a cycle, the squelch noise also sounds abnormal to me.

It is possible to replace certain sub assemblies, but the issue is how you go about diagnosing the issues; which is where it becomes tricky. It sounds like the the issues could be an Accumulator or Accumulator Pump (either the pump is supplying borderline acceptable pressure and needs to run too often to "top it off" or the Accumulator is leaking pressure), but it is also possible there is an internal leak in the master cylinder portion allowing pressure to bleed back into the return circuit, and/or a similar leak in the ABS Solenoid pack mounted directly to the master cylinder portion.

The reality is that you're better off replacing the entire assembly as a whole than trying to replace parts one at a time with this system. As for paying $3000? That's up to you, there are other options available to you that may make the repair a bit more affordable.
-Pay the dealership the money and have a 1 year warranty on the part and work done (that may be worth the high cost? It's up to you on that one...)

-Call the Parts Department and acquire the Part Number for the unit and then shop online.
(For example BRAKE BOOSTER ASSY, W/MASTER CYLINDER. BRAKE MASTER CYLINDER (GRN21# for 2008 TOYOTA 4Runner. #4705035031 appears to be the correct unit for your vehicle) then have the dealership install it for you (they mark up the price of the part to closer to $3000 usually vs. the almost $1900 on the website.)

-Locate a used unit from a salvage yard for cheaper (there are inherent risks with this as you don't know the vehicle age, service history, ect. of the unit; but they are often fairly cheap.) and have the dealership install it.

-Live with it until the unit goes completely out?

Either way I recommend you have a Dealership do the repair or a shop that is very familiar with the Toyota system and has the appropriate scantool to bleed the system afterwards.

Yup, ur brakes/MC is most likely on its last legs..............mine failed couple of weeks ago. and the pumps were kicking in every 90secs with the ignition on...and every time i engage the brake pedal.........

didnt have the $$$$$$s to buy a new unit, bought a used unit under $300 from a forum member, and would install soon............just trying to figure out to manually bleed the system after the install, lots of useful thread on this issue............just search

X2 time for a new or used unit. I was also quoted the 3000 for the part alone. I ended up buying a used unit with a year warranty for 600 dollars shipped to my door. Then had it installed. Total around 1000 dollars. Good luck.

Had to jump the battery last weekend in my 2006 Sport Edition V6 and appears if the smart feller who gave me a jump crossed the cables causing a mess in my fuse panel! Everything working good except for the ABS light is on and do not have power brakes at all. Mechanic says it is the whole power brake booster and the part alone is $2300-$2700, but that makes no sense, since it is not electronic. However, with the ABS module attached I could see it being the problem given the circumstances. I have a problem needing to spend $3000.00 on a part for a vehicle which might be worth $3000.00. Truck has 260k miles and still runs fine, just heartburn over this. Any thoughts or mechanics in the NoVA area would be appreciated. Thank you in advance.

you can get a used unit on ebay or from a salvage yard for around $500 with money back warranty it works.

no way would I buy a new one at those prices when failure rate for them are very rare

check the 40amp abs fuse in the fuse panel if its broken.