TOPIC: Does anyone knows the tricks to groove a Previa 1993?

Carlos, do not plug egr unless its leaking vacuum we must keep the ecu happy. put new gasket on throttle body and ship it . That is a simple one you have. You should have alot of power and increase in mpg. The idle should be normal if no vacuum leaks.



Dan

Thanks Dan!
WHere you able to notice that I JB weld two sections of the TB that will be flushed against the gasket? Is that okay? Do I need to cap any other port, either R, P or E?

Who do you recommend for me to get the ship from?

Dan I capped the pcv valve with a screw and some glue. Is that okay to do?

carlossavesgas do not cap PCV valve -- cap the place in the intake manifold where the PCV valve line is when starting the reroute of line to a place in the air stream before the throttle body. PCV valve must be allowed to continue to work just the vacuum air to PCV valve is being moved.

geraldc

Hi Carlos good work on yer maiden Groove voyage!

Your filling of the IAC idle speed air ports in the TB base looks OK. If idle speed is insufficient w/ A/C might open those holes you cut in the epoxy a bit. but just go w/ what ya have and see.

I'm not quite sure about the other small hose nipples on this one. I'd leave well enough alone for now.

Dan's right, dont block the EGR, but instead test it to see the diaphragm holds vacuum w/ a Mityvac or similar.

PCV-- don't plug or block the PCV valve itself. you want to follow the hose from PCV itself to find where it leads to manifold vacuum. Cap the PCV vacuum source off, then re-route the hose to passive vacuum before the TB. Either the main air feed duct from air cleaner or the breather hose that directs air into crankcase usually into the valve cover. Air inlet duct or breather considered passive cause both connect before--above--the throttle plate, that is before manifold vacuum.. Usually it involves installing a tee fitting and connecting PCV hose, maybe a little new hose to hook it up. Sometimes ya have to get creative w/ this.

I think Dan was just sayin' this is a simple Groove job by sayin' "ship it"...

Your Groove looks good. IF you are unsure about these extra mods w/ PCv hoses etc. then just put it together, do the computer re-learn and see what ya got, I think this one ought to do very well. you can always go back in and do extras later. IF you are unsure about the pcv egr and other systems, then study in the Index here and elsewhwere. Don't wolf it down all at once, go one step at a time.

Excellent pics, Carlos, Thank you!

Tracy G

I get so tired of repeating myself, but I guess that's just my job.

1) Make any and all adjustments according to ONE protocol: Make your changes SMALL and INCREMENTAL. A few times down the pipe is all it will take to show you the wisdom behind this.

2) NO ONE is better able to guide you than those who have been where you wish to go. In this case, that would be me.

3) T
he FIRST set of work that is done is Groove the Throttle Body and CAP the SOURCE for the vacuum supply for the PCV system. Do more, and do so at your own risk. Do more, and you will VASTLY complicate any troubleshooting you may have to do.

Fellers, I want you all to be successful, without doubt. BUT!!! If YOU want to be successful, I would suggest you follow what someone who HAS BEEN and CONTINUES to be successful, as they are the best guides.

As the most successful person in applying this technology, I have a couple of things to say. Go back to the manual and follow what it says FIRST. Go to the Training Video and follow what IT says FIRST. AND NOTHING ELSE!!!!

Please, my family, as the patriarch I feel a responsibility for you. Honor my sacrifice(s) and follow my instructions. Don't add to (nor take away!) from what I advise until you are more familiar with the engines and the ECU's AND the way they respond.

You will be very happy that you did.

Now, God Bless you ALL and good night.

I love you.

Ron

Hello Tracy here are a few more pictures of this Previa

PCV re routed to a vacumm line located from the power steering to the air duct after the filter

these two ports are now capped which were attached to (1 to power steering vacumm) (2 to a some sort of pressure device with a screw and a spring , the screw is made of plastic)These 2 are on the lower side of the manifold 2 inches from the TBody.

I connected the 3/8 hose to the smaller 1/4 hose that is attached to the power steering pump.
I have driven it like this for a few weeks and have not seen the improvement desired.

Then I decided to leave the 2 two hoses attached to the manifold were they were before to see what would happen. And something did happen. The exhaust pipe by the converter started to make more noise than the usual. And now I am wondering which way is best.

Carlos Ramirez reporting on Previa from Tallahassee Fl

This maybe hard to see but I hope you understand. This is simply what I did with the hoses. I think I ought attach the PCV hose closer to the TB right onto the duct before the TB>

Scratchin' my head here Carlos...

Ya sure there is a vacuum hose to power steering? Never saw that before.

Here's an idea. Is there a vacuum hose diagram on a sticker under the hood? If there is take a pic, then print a blown up copy of it. Then you could draw/diagram the mods to the hoses on that, then take a pic of that and post it. It sounds like you have the idea of re-routing PCV down OK.

Not sure about the exhaust noise. Are any of your hose mods involving anything going to exhaust system. Is there any kind of air injection, air pump, air aspirator//reed valve system connected to the exhaust?

Pics showing the hoses in total and the stuff on the manifold (the thing w/ the screw/spring) could also help. Thanks for sharing, Carlos!

Tracy G

Good morning Tracy!