T-sport - Could somebody post photos of standard vacuum routing

[dennis10]

As in the title, please could somebody share some photos of their standard/oem vacuum routing from airbox to manifold/ throttle body / SAI and surrounding area?  

I purchased a car with a K&N typhoon fitted and I am going back to stock, but the vacuum routing is all messed up.  I have Engine management lights / TRC and VCS lights on and trying to tally it up with the image on the bonnet is causing headaches as I don't know what the parts are in the diagram or what they really look like - photos are much easier

Thanks in advance 👍

[oldcodger]

You might be able to work out the original layout from this KN fitting guide.

https://kandn.com/instructions/69-8751_inst.pdf

Also you might need to reference a diagram for the original parts, so have a look here  -

https://www.megazip.net/

[flash22]

k&n badly screws with the MAF sensor, what code(s) is it throwing

edit, this may help

https://toyota.7zap.com/en/eu/corolla/153550/zze123l-dgfgfw/1/1706/173885a/

https://toyota.7zap.com/en/eu/corolla/153550/zze123r-dhfgfw/1/1201/120224a/

https://toyota.7zap.com/en/eu/corolla/153550/zze123r-dhfgfw/1/1708/173171e/

https://toyota.7zap.com/en/eu/corolla/153550/zze123r-dhfgfw/1/1703/173528g/

[dennis10]

Thanks for the replies chaps - I do have the K&N instructions, but zooming in on the black and white photos gives you a 3 pixel image so it's quite hard to decipher lol

I've spent hours trying to find a decent set of photos or images showing the correct stock routing of these pipes, hoping somebody will pipe up with a few soon - in the meantime I'll take a look at what you've shared, thanks again

[APS]

Just dotting the i's... I take it Google has been of no help then?

Ironically, we never took any photos (that I can remember) of the engine bay of our T-sport as we rarely needed to do anything to it. 

[APS]

Of any help?? 
https://www.toyotanation.com/threads/please-post-pics-of-2zz-vacuum-line-orientation.1272097/
https://imgur.com/SPzivL0,yzZZqHj,wkXaeD7,HsD3mul,fCeQXQf

 

[dennis10]

Ok so I have managed to refit the OEM airbox and have definitely got the correct vacuum routes from around the throttle body and exhaust manifold area up until the 2 valves that sit on or near the airbox (one is brown, one is blue, with 2 nipples on each) but after that I was pretty much in the dark.  The round plastic unit that is attached to the airbox on the bulkhead side has a snapped vacuum nipple, so I couldn't connect anything to this, I ended up connecting the bottom brown valve nipple to the little vacuum nipple on the left side (from the front) of the airbox as I had nowhere else to connect it to.

The long and short of it is, I disconnected the Battery and so far no lights have come back on the dash, but I think it took about 60 miles last time, however now my revs are staying quite high for a long time - eg starting from cold it goes up to about 2krpm for ages and stays there only dropping over the course of about 20mins to about 1100rpm, not really getting any lower than that.

I'm assuming that I have a vacuum leak or something somewhere, would this cause my revs to hang and stay high?

 

Really could use a photo or two of where these valves are supposed to connect to, or at least how I can plug a vacuum leak without getting warning lights or what to do about the snapped nipple on the little round unit at the back of the airbox

[flash22]

If you look at the last 2 zap7 links I posted, you can see the routing i can put them together if it helps

[flash22]

the round part with the nipple broke off  is the diaphragm that operates the cold air intake flap you can just cap this pipe off

one of the solenoids is for the air box, the other is the fuel vent valve

pics here may help (scroll down)

 

[dennis10]

9 hours ago, flash22 said:

the round part with the nipple broke off  is the diaphragm that operates the cold air intake flap you can just cap this pipe off

one of the solenoids is for the air box, the other is the fuel vent valve

pics here may help (scroll down)

 

9 hours ago, flash22 said:

 

 

9 hours ago, flash22 said:

 

Thanks alot for your help on this. I'd actually found that thread while hunting down my issue, but because the guy wasn't hugely confident it was the correct route for the vac pipes, I kinda discarded it.

If I follow that route, it shows the bottom hose coming from the (snapped on mine) round valve on the back of the airbox going round the airbox to the bottom outlet on the brown valve. What do I do with that hose considering that nipple is snapped off and I can't connect it to the bottom outlet/nipple on the brown valve? And what do I do with the bottom outlet on the brown valve if I have no hose to connect to it?

Does anyone know what should be connected to the SAI valve behind the passenger side fog light?  Any vac hoses or anything?

[flash22]

That round diaphragm is the cold air intake flap

you can cap that pipe off with a screw/bolt

I will see if I can find the uk/euro service info - the site i usually use has been down for a few days

[flash22]

The grey solenoid (blue plug) is for the vent purge a pipe comes from under the car to the valve then from the valve to the intake

the brown valve controls the cold air intake flap on pipe comes from the engine through a check valve then into the solenoid (no indication of a tee piece) a pipe then comes off the valve to the diaphragm that controls the cold air intake flap

clearest diagram i can find

https://toyota.epc-data.com/corolla_runx/zze123/185885/engine/1703/?partno=9009900289

 

[dennis10]

1 hour ago, flash22 said:

The grey solenoid (blue plug) is for the vent purge a pipe comes from under the car to the valve then from the valve to the intake

the brown valve controls the cold air intake flap on pipe comes from the engine through a check valve then into the solenoid (no indication of a tee piece) a pipe then comes off the valve to the diaphragm that controls the cold air intake flap

clearest diagram i can find

https://toyota.epc-data.com/corolla_runx/zze123/185885/engine/1703/?partno=9009900289

 

Honestly thanks for all your help - brilliant so far!

I think the blue plug valve is connected up properly and I've not touched that side of things thus far - it also doesn't see to really affect the vac piping in anyway, so am not so worried about this.

So if the brown valve connects to the round valve that has a snapped nipple at the back of my airbox, could I dispense with this valve altogether and either cap both vac nipples on it or delete altogether?  What can I delete out of this that will not cause an engine check light or idling issues?

I'm trying to work out what is needed to make it idle correctly in terms of vacuum routing and what is just extra crap thrown in that can be dispensed with.

I also still haven't worked out what the vac nipple does that comes off the left hand side of the airbox (if looking from the front)

 

Good lord all of this would be sorted if I could just get a reliable photo or two from somebody's engine bay showing working vacuum routes 🥴

[dennis10]

I've found this diagram, which shows the "vacuum switching valve for Intake air control valve" connecting to the throttle body and the "vacuum switching valve for AIR" - Am I right in saying that this helps to control the idle speed?  In which case I surely need all the other stuff such as the valve which has a broken nipple?

 

 

 

[flash22]

Not to sound like a broken record the round part is a diaphragm this controls the cold air intake flap, leave the solenoid, cap the pipe

that is a early diagram the diaphragm has 1 pipe as the solenoid has its own vent

this thread shows the celica air box diaphragm a flap

https://celicahobby.com/forums/ubbthreads.php/topics/18933/intake-butterfly-how-to-remove.html

 

 

[flash22]

Don't know if you have worked this out yet

there are 2 main VAC lines one from the top of the throttle body large blue check valve and the other comes from the black solenoid under the throttle body, still on the hunt for tech info

 

[flash22]

https://autopil.ru/autopart-product/5ecb8a205f9fad4f48c2e148/

[dennis10]

Cheers for that airbox advert - has some good photos in it - Can I just check the direction of the 2 pipes on the vacuum solenoid.. the hose coming from the throttle body connects to the top nipple on the brown valve and then the bottom nipple routes around the airbox to the intake flap (if you still have it connected)  If I'm not using the intake flap, do I just cap off the bottom valve?

[flash22]

Throttle body - check valve - t piece - air box

                                                        |

                                                        |

                                                      Brown soleniod -------- flap (cap this pipe)

 

the black solenoid under the TB is for the secondary air that goes into the manifold

 

                                                        

                                                        

 

[dennis10]

19 hours ago, flash22 said:

Throttle body - check valve - t piece - air box

                                                        |

                                                        |

                                                      Brown soleniod -------- flap (cap this pipe)

 

the black solenoid under the TB is for the secondary air that goes into the manifold

 

                                                        

                                                        

 

Brilliant, thanks for that!

[dennis10]

In the end, I voted for stripping down the throttle body and Idle Air Control Valve and in the process ended up mangling the stupidly placed phillips head screws (why the idiots at Toyota used screws instead of bolts is beyond me) that secured the IACV to the TB.  Finally managing to get it off using heat from a lighter/blow torch, I mangled the rubber gasket in the process.

 

I opted to purchase a brand new Idle Air Control Valve from eBay (Looks like a Denso refurbished unit) which comes with a gasket - I had to wait for delivery over the Christmas period with the intake stuff all stripped down and car not running, but today I finally got my new Idle Air control valve and gasket, fitted it all back together with K&N short ram intake pipe and a new filter on the end - Also opted to replace every vacuum line with new silicone piping to rule out vacuum leaks.  

 

Fired the car up and my issue is now thus:

 

It idles on a cold start at around 2krpm which I think is too high, eventually it starts to drop a little, say to around 1500rpm, but if I engage/disengage the clutch either when stationary or driving it will rev up and down a couple of times, before settling again.  It has this issue when the engine is both hot and cold, when hot it seems to idle at around 1100rpm.

 

Any ideas on what to look at now?  Have I got a faulty new IACV?  There is another plug/switch on the throttle body, could this cause the above issue of hunting / rev fluctuation when dipping the clutch?