2014 with Magnuson SC and brake nightmare

My guess is they’ll diagnose as a abs pump (and possibly a booster as well) no matter what issue really is. That gives em some $ to work with to figure it out. That and I’m pretty sure these abs pumps are shit anyway. See all sorts brake related abs recalls for Tacoma’s, Prius and older tundras. Just not the 2014 (yet). Also read from others where they said the newer abs pumps had “improved logic”. Not sure I believe that BS but I don’t doubt they’ve got some issues w these abs systems either way. Just not convinced it’s my issue still at this point.

 

I've made a few of these brackets but I'm at work and not sure when I will get home. Some food for thought.

 

Finally fixed this nightmare! For whatever reason never noticed the issue for 5k miles when installed the Maggie. After redoing entire brake system, multiple times, countless nights weeks months cursing Toyota, driving around w ABs engaging and brake pedal going rock hard after 3 or 4 light pedal pumps, I have finally resolved this bs. Installed a Leeds bandit electric brake booster pump... disconnected from engine vac, and brakes are doing much better. From what I understand from the best tech I could find familiar with supercharging the tundras, the 2014 is unique because it has a different brake vac system than the later models. (Although they had never ran into this issue with them they had not installed a Maggie on a 2014...) My guess with the 2014 when they upgraded the tundra and put the bigger body and larger brakes (and 1st year redesign) they just skimped on the brake/vac requirements and the Maggie affects the vac drop just enough to put in barely within where the vac supply can keep up with the booster demands (especially with bigger wheels, city driving etc etc). Anyway brake pump resolved it. I can still get it to run out of vac but not by accident and not unless purposefully hitting pedal like 5 or 6 times in succession for no reason. So now drives great and I’ll take it. I guess the brake design changed slightly on 2015 then or 2016 and no one seems to have run into this. Maybe something changed after 5k miles or break in after sc causing it to drop just enough vac supply to become noticeable. Or maybe it is an internal issue with valves but just a slight one enough to affect this. Either way after dyno tuning the truck it’s everyone’s assessment that it just wasn’t worth taking sc off or anything further if a pump will resolve it as engine is running great. Truck put out 495rwhp/ 515torque at the wheels on the dyno.

 

Interesting. I have a 2014 with TRD SC and have never had this issue. Glad you got it resolved. Thanks for sharing the resolution.

 

Same thing on my end...2014 TRD SC'd...I am grateful you resolved this issue...I couldn't imagine the curse words I'd be spouting out if I had been experiencing what you have had to endure...Thank you for sharing the resolution!

 

Maybe its asked earlier in the thread... but is there a check valve between the booster and engine or booster and vac pump ?
Vac should only ever go in the direction of the source.

 

@Crunch527 yea can you pump the brake pedal 4 or 5 times while sitting still and see if it starts to get firm? If so try it while rolling slowly? You don’t see any difference in pedal or brakes if so?

@Dragracer_Art yes checks valves all good

 

@Crunch527 also, (assuming you aren’t seeing any brake issues) was your SC kit the original TRD Toyota one or a later model Magnuson aftermarket and when did you buy it or have it installed? I know the air intake on mine that came with the Maggie is larger than the original toyota branded trd sc Maggie that came from Toyota originally. I just bought my sc 6mos ago. Perhaps they have different effects and it’s the newer sc that is causing more vacuum conflict if so.... hmm

 

What were the vac numbers you were receiving at the booster? And do you know what they are supposed to be? Would be curious if the ID of the vacuum lines is different between the years..

edit: missed a couple posts. Yeah, I think sub-20 is low. I believe it should be around 22-23 or so. Glad you got it figured out!

 

@dittothat its a 3/8id line. The new booster vac does have a 1/2in line though. I did try changing that out too a while ago to a 1/2 but didn’t matter. The problem isn’t so much the vacuum I think but the SUPPLY or amount of vacuum. It’s around -19inhg in any event which is within spec for that engine. Problem is just can’t keep up with the demand and takes too long to replenish the booster.... so unless each stroke is requiring more of that pressure/or vacuum than it should be it’s a supply issue. I only mention the amount a pedal stroke takes because I did fiddle w the pushrod adjustment an awful lot in this process and not exactly sure if that’s right still. I believe it is. I lost track but think I have it sitting 2mm in front of the piston at this point on mc. If anyone with a 2014 out there can count the threads on their pushrod behind brake pedal I can confirm it.... that would be helpful. I think I have it about 5.5 threads from the U bolt thing on end of it where attaches to the pedal mechanism

 

My intake is the TRD kit...for whatever reason the air box I got is the TRD version, not the all black larger one that (after the fact) I thought it was to come with...I had the SC kit dropped shipped to a dealer and installed...I never saw the parts until the truck was done and at that time didn’t realize there were different air intake versions...it was prolly a year or longer before I started to realize there were different intakes so I never pursued it.

Still isn’t 100% clear to me as far as why the different versions of air intakes? I realize the SC needs more air, but it is odd to me that my intake is the TRD (red letters) version and others I see in pics is what appears to be a larger yet all black intake housing. Maybe the 2014s needed the TRD intake vs the black one? Dunno.

The only brake issues I have had are driven by my silliness. I went to an aftermarket stop tech or powerstop kit (cant remember which) and it sucks ass. The OEM rotors and pads lasted to like 70K and I went and second guessed that some aftermarket brake pads and drilled/slotted rotors would be better. NOPE..takes more to stop the truck and I had them bleed the brakes after they swapped over the rotors and pads to be sure. The pedal has always been good but these new brakes just dont have the same stopping power as the OEM. I am going to have OEM pads and rotors installed next week.

Jolobeans - do you have a pic of your air intake?

 

Yea that’s from when magnusson was manufacturing them for Toyota (they were badged “TRD” supercharger then. Then Toyota stopped supporting them oem, and Magnuson took over selling them as aftermarket. At some point that intake changed. Also there are 2 different kits. One for the flex fuel and one for the other non flex. Assuming most is the same but def the intake is different. Is a much larger filter than the OEM and runs a K&N. Not sure I like it but no idea how to get a non oiled filter that would fit. Changing brake rotors and pads shouldn’t affect air in the lines at all. I also just put some tow hauling power stop rotors on it. They feel okay- so far. I also did the goodridge steel lines just since had everything else ripped apart. No idea why I have this vac issue though. Every car I’ve ever owned had enough vacuum resupply I could sit there and pump brake pedal 40 times in a row and never lose brake power or pedal go soft like this was (after 2 or 3)

 

https://drive.google.com/file/d/1Zt7CE78q5mYcl9w3Pei-wDAnaAOZlYAM/view?usp=drivesdk

@Crunch527

 

Glad you got it solved @jolobeans. I've been keeping an eye on this thread. When you get a chance, you mind sending a link to the brake booster you purchased that fixed the issue? Was it a difficult install? I'll be installing a Magnuson on my 2014 soon.

 

I bought my kit in 2014 and had it installed with 6700 on the odo. Tracking on the history with Magnussen...was why I was comfortable with the TRD S/C due to previous dealings with Magnussen and the quality of their products. Glad they picked it up when Toyota bailed in 2016. I intentionally stayed away from FF trucks.

 

Here's a pic of the intake I have that was on a 2016 Non-FFV (totaled via hail damage at 6k miles) installed on my 2011 Non-FFV. It does look taller, and has the different inlet hose to the throttle body.

 

That's a pretty nice, flat torque curve.

 

Do you have baseline hp/tq numbers?