The Tragic Tale of ElSuperPinto

Tell us why it wouldn't work, not that it really matters but it might.
Short answer: Because the 4th-gen Prius is brake-by-wire.

Long answer: Because the 4th-gen Prius is brake-by-wire, meaning that the master cylinder isn't so much a master cylinder, as it's a hydraulic multi-purpose device with the primary function being to give the driver of a Prius the feel of normal hydraulic brakes. The module on the side of it is there to use inputs from various sensors, including the yaw rate sensor in the steering column, the brake pedal position sensor, various pressure sensors, the wheel speed sensors and so forth and so on to decide how much of and which type of braking to apply. The "which type of" braking comes into play because the majority of the time, the Prius isn't using it's hydraulic system and brake pads to stop the car, it's using the electric motor for regenerative braking, which not only slows the car down, it also recharges the high voltage battery. While stepping on the pedal connected to that master cylinder does cause brake fluid to come out through two of the three ports on it, it's only designed to do so under certain circumstances, in others, it bypasses internally and sends the fluid to a "stroke simulator". In addition to all of this complication, there's also the fact that while the assembly I got DOES include the brake booster, it's not the WHOLE brake booster. If you look up at the hydraulic diagram, you'll see the mention of a "brake booster pump assembly". That's not internal to the assembly I ordered and received, it's halfway across the engine compartment. That guy gets fed brake fluid via gravity via the nipple on the side of the master cylinder reservoir through a hose, and then sends pressurized fluid back to the booster's inlet port. Without that, no boost.

On top of ALL of that mess, when the Prius master cylinder's control module goes into failsafe mode, it does so by reverting to behaving as a manual brake master cylinder, meaning it won't energize any of it's various internal components to do a damned thing to help, and even after consulting a Toyota master technician I've known ten years and putting our heads together studying the various wiring diagrams, hydrulic diagrams, and parts catalog pages, neither of us is convinced it could or should be tried. The one thing we both are sure could be done is using a relay that's triggered by the stoplamp switch to turn the accumulator pump on and off, but we can't be sure the pressurized fluid would actually go where we want within the master cylinder assembly.
 
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Nothing super exciting happening yet, still in the parts-gathering phase. Here's the exhaust manifold studs and the EGR delete plate I grabbed off Ebay this week:

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For the record, in light of certain recent actions elsewhere on the forum, feel free to :leghump: around in my build thread as much as you want. I may delete the extracurricular stuff later to bring the page count back down and bring it back to substance (in fact, I have once already), but the thread itself will not be deleted, and the ****y can resume accordingly (like it did within the first couple of posts after the last cleanup).

Hell, I join in on it frequently, the recent "deez nuts" exchange was proof.
 
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Drove ElSuperPinto to work today... and it tried to kill me. On the frontage road, I stabbed the loud pedal like I always do, and it tried to come around on me. I was puzzled as to why until I got to the shop and it was dripping water out of the ass end of the car. I opened the trunk and the spare tire well was full of water and a lot of the rest of the trunk was wet!

Guess who spent three hours after work cleaning and drying things out? I went ahead and installed the new taillight seals that were in the trunk while I was at it. The drive home was uneventful.

In weird news, the EFI system, while still not letting the car idle, umm... quit starving it for fuel on the top end.
 
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In weird news, the EFI system, while still not letting the car idle, umm... quit starving it for fuel on the top end.

At least it sounds like progress. :shrug:

Drove ElSuperPinto to work today... and it tried to kill me. On the frontage road, I stabbed the loud pedal like I always do, and it tried to come around on me. I was puzzled as to why until I got to the shop and it was dripping water out of the ass end of the car. I opened the trunk and the spare tire well was full of water and a lot of the rest of the trunk was wet!

So..... Bad weatherstripping or it is that rust hole you found that's giving you trouble?


.........OR a gremlin?!?!! :hide:

The_Gremlin.jpg
 
So do you have a name picked out for your gremlin? I think something like ElSuperPita might work well, kinda tie him in with the family. :jester:
 
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So do you have a name picked out for your gremlin? I think something like ElSuperPita might work well, kinda tie him in with the family. :jester:
ElSuperPuto.

It translates to... well... look it up, not saying that on the forum.

It's a lot of self-inflicted stupidity that added up to yesterday's cleanup efforts.

The car is stuck outside because there's no room for it in the garage.

The vinyl roof removal included removing all the trim around it, leaving some exposed holes in the C-pillars. Some water can intrude there in a heavy rain. I also hadn't gotten around to replacing the tail lamp seals when I did the all-red conversion, so some water more than likely got in through there. Then there's the aborted rust repair that's currently covered with Gorilla tape, which, while I doubt that was a source of the water intrusion, is a possibility.

I really should just sell the thing to someone that'll take better care of it.
 
Who could take better care than you?!
Someone who isn't going to let depression, apathy towards cars due to his career, and other things in life lead to months, and at one point over a year, of neglect at a time.

All of that said... I did drive it for the second day in a row for the first time ever today. It's sitting right outside the shop right now.
 
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So I drove ElSuperPinto to work yesterday, and it ran fantastic. Then my co-worker wanted to go hit our favorite dive after work for a couple of beers... My house is along the way, so I decide that rather than drive a car with no A/C, a stall converter, and a tempermental EFI system downtown, I'll just switch it out for the 4Runner along the way.

I damned near didn't make it the less than two miles to the house. The car started stalling every time I released the gas pedal, like the IAC suddenly closed and won't open instead of the other way around. Luckily, being a former drag car with a Hurst ratchet shifter, I don't have a neutral safety switch, so I just hit the starter button every time it stalls to get moving again. I'm about $1000 worth of parts away from putting the new 4.6L mill together (including about $300 worth of stuff from the junkyard), and a $400 rebuild kit away from rebuilding the TR3650. I really don't need the MSD EFI system to start being this damned unpredictable.
 
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Fun times! Sounds somewhat like the last drive with my car. Well, except for the restarting part.... And the 2 mile's away from home part.... And mine's not fuel injected..... Nor an automatic..... And I wasn't going out afterward, I was on my way home from being out.....

BUT - I also have no neutral safety switch, so there's that!! :banana: :rlaugh:
 
How much more do you think you'll tinker with that EFI system before you just rip it off the car and throw a carb on it?
I'm not, on either count.

The MSD Atomic is going on Ebay when the 308 comes out of the car. I see zero point in putting any more time or money into the old pushrod powerplant at this point. I'm going to fiddle with the idle speed screws and unplug the IAC tomorrow and get it running again (assuming my working theory is right) and run it like that the whopping 1-2 times a month I drive the rusty old thing until the 4.6 is ready.
 
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