wmflyfisher

Sorry if this has been covered guys. I could not find it. The box I removed from my 02 had one hose going to the FPR tube and thats it. Where should I run this hose?? My motor does not have that nipple coming off where most people connect it with a plastic T fitting. Can I just plug it? There was no vacum when I had it running. Any help would be great.

97ltd4x4

Yes,you can plug it,you can even leave it disconnected,does not matter...

The FPR on the 5vz,are set from factory by a set screw and spring...They are not controlled by vacuum like the old type...Its kinda a weird inbetween thing Toyota did..between the vacuum FPR and returnless type...

You can distinguish between the two, vacuum operated will be connected in the manifold,between throttle body-engine(vacuum)...Set type will be plumbed someplace between the air box-throttle body(no vacuum)...

I have read a lot about the ISR mods on here and have not chimed in,but you do not have to plumb it back in to the air cleaner/pipe assembly...Also you will see no change on the scanner short or long fuel trim if you disconnect the line....On the older ones you can see it...will immediatly spike and lock the O2 sensor..

wmflyfisher

Perfect answer and just what I wanted to know.

Thanks

Hophead

Does this info apply to all 5vz's? I just did the ISR on my 99 motor. In my search for an answer I have read that you can plug it, tap in into the intake manifold or tee it into what seems to be the line running from the evap box back to the intake box post filter.... Seems that there wouldonly vaccum at the intake tube when the TB is open, were as the intake manifold would have relative constant vacuum......

97ltd4x4

It applies to every combustion engine made,including the 5vz ...Put a vacuum gauge in the intake/air filter track...Your not going to see any,cannot create a vacuum without a pressure drop,since there is nothing to drop pressure= atmospheric pressure...especially if the throttle opens..Throttle open=low vacuum,throttle closed=high vacuum......You might see the needle just come off zero,when you snap the throttle plate,for a split second if you have a good vacuum gague with a short hose plumbed very close to the throttle plate......Otherwise it stays at atmospheric pressure...

twitchee2

the 02 is different then others, theres is that capped off one on the top of the manifold. I used that peice of metal tube thats just sitting there and hooked it up to the capped off vacuum thing.



you can kinda see it. Its the shiny vacuum lines on the top of the motor.

wmflyfisher

Yeah, and I see the tube on yours where the hose connects to the FPR. You didn't cap that one. Not that it matters, I can just see it. Just like mine looks.

Twitch, I saw the thread that stated how you gained soo much from this mod. I've added a trueflow airfilter and performed this mod. Honestly I can't really tell a difference. I have not done the deckplate mod yet though and havn't refigured my gas mileage. Maybe its better now. We will see!

twitchee2

yeah, when i did the mod i was living up at 8,000ft and up there i really noticed quite a difference, but now that im back at sea level all it really does is make it louder and sound cooler. i still only get about 18mpg so it didnt do much. im going to be getting a trueflow here in about a mo.