Totaled Tacoma - Rebuild in Process!

I don't know much about forced induction, but to me this bypass valve is not working as intended. I took a video showing how it only opens for a second under heavy throttle, even if you stay in the throttle. And it won't open at all under light throttle.

Also, it does not make the super charger wine. Every other video on YouTube, the whine is very loud when revving at idle. The only time I hear the super charger whine is in 3rd gear under load. No other gear makes the whine.

https://youtu.be/gcd9W_fyCgo?si=wajdaxFZXNJQAMkR

Anyone else have any opinions? The truck is back at the shop again as well.

 

Have you confirmed your findings with a boost gauge? Looks like it’s working properly in your video. There is no engine load in idle, so it would be very difficult to build boost to see the bypass open for long periods of time.

 

I understand there is no load on idle and the valve should be open in that case, however, the valve closes and then opens immediatly even when the throttle is still open and the engine is at high RPM.

Shouldn't it stay open until you release the throttle and the engine goes back to idle?

Edit: The shop will be hooking up a boost gauge to check if boost is being made.

 

Since manifold pressure is proportional to engine load, you cannot build manifold pressure (to hold that bypass closed) reving the engine with no load.

I changed from the MP62 to the 1320 supercharger, and these newer chargers build boost earlier and more effortlessly(obviously design) and are not as loud as the older MP62 units. I prefer the 1320 units as it seems to build power at lower rpms.

 

Thank you. Did not know that about manifold pressure.

Still odd that you can't hear it at all revving it from the engine bay, while every other video on YouTube of the new tvs1320 you can clearly hear the whine.

Also, it's only audible in gears 1-3, with 3rd gear being the loudest by far (1st and 2nd are more of a whisper). 4th and 5th have zero whine, and the truck feels like an old dog below 3k rpm in any gear, so there is no low rpm improvement being felt. There is also still the fact that I can hear a lot of escaping air/wooshing sound when on throttle and accelerating.

The shop has checked for vacuum leaks so far today and found nothing. They did a smoke test as well.

They have emailed Gadget at URD for advice and will be hooking up the boost gauges for a test drive later to see if boost is even being made.

 

Have you considered using a standalone ECU?

What you are describing seems to be similar to my experience with the URD 7th injector. I was never able to get the URD 7th running properly even after countless hours of “tuning”. Going to a Haltech standalone is one the best mods I have done to date.

 

I did look into the Haltech you mentioned earlier, seems a bit over the top for what I need right now. Plus, I have to hold off on large purchases for the next month until I close on my new home (hoping final build inspection happens the last week of June).

The shop owner has done 2 previous installs of this supercharger from URD, including on one of his personal vehicles, and he did not run into any issues with those.

The only thing new with my install is the use of the 7th injector kit. His best guess right now is something with the tuning box may be wrong (or possibly the wireing plugs for the box), and he is hoping Gadget can shed some light on what to check.

I did read on another thread someone saying the tuning box couldn't read the engine RPMs, but that was on an older 1996 Tacoma, and that URD said it should not effect newer Tacomas.

But we'll keep investigating. I'll continue to use this thread to post my thoughts. If I say something that makes no sense or sounds dumb, let me know, I'm not the most knowledgeable when it comes to engines or tuning.

 

Almost 1 year to the day that I ordered the Yota1 rebuilt 5VZ she's in and purring. It's amazing how much less NVH there is with the rebuilt.

I don't know if there's a way to find out the exact core I have, but I'd like to think it's yours, thanks!

 

That is awesome! Looks great.

I don't know how easy it is to see, but a Google search shows someone mentioning the VIN being rivited on the driver's side of the engine block.