Hi guys,

Took the celica out last Saturday for its first run on the road in nearly 12 years. Everything went well and now I am on the snag list before the MOT in a couple of weeks.

I have been looking into the vacuum system and need help with the layout. I need to know what is connected to the charcoal canister in terms of the TB connector of it. I can find diagrams showing how it is routed on an engine with egr but not for one without. I have only one vacuum outlet directly above the throttle valve but don't have any info on where that goes before the charcoal canister. Is it simply a case of a direct connection with a one way valve fitted allowing flow to only travel towards the TB?

Also, is the boost pressure sensor located under the intake manifold and where does it get its feed from? The outlet from the waste gate actuator that normally runs towards the back of the engine has been disconnected and blocked yet the dash cluster boost gauge still works??

Does anyone have a non egr diagram or clear picture of the area around the distributer / charcoal canister I could see?

Thanks in advance,

Mark

My memory is hazy on the standard 185 setup.
Can't help on the charcoal canister bit. I would hazard a guess that you're right about it connecting direct to the manifold via NRV although I seem to remember seeing a valve mounted next to the canister. This may have been a UK car though, or a 205.

Turbo pressure sensor is on the bulkhead, from memory about middle on the 185. Can't remember which port on the plenum it comes from. (205 comes from front middle near throttle body). The dash gauge and ECU are both driven from this sensor.

The second port of the wastegate actuator pointing towards the back of the engine normally goes to the TVSV valve which allows the ECU to increase boost. This is normally blocked in order to run an aftermarket boost controller.

There are 2 valves under the inlet manifold.
TVSV (mentioned above) provides a bleed from the turbo actuator to the big 'fresh air' pipe which runs from idle valve on the bottom of the throttle body back to the inlet pipe.
TVIS takes a vac. feed from the inlet (bottom of runner 4 from memory) to drive the TVIS actuator via the TVIS valve.

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If at first you don't suck seed, try drier grain.

Thank you. Makes perfect sense of what I have seen. I thought the bulk head sensors were just air con related which is why I didn't consider it. The only internet reference I can find regarding another switch near the char can is a tvv for the egr system. I will just go direct to the tb for now. There is an aftermarket boost controller that I have fitted, its only a cheap manual one with a ford focus egr vsv at the end of it, just so I can select waste gate pressure to run with for a bit.

Am I right in thinking if I don't block the boost pressure sensor I will soon hit FCD?

Again thanks for your help, its come along nicely over the last month or so, hopefully try the mot in a couple of weeks...

From my past experience, disconnecting the 'turbo pressure sensor' on a 185 affects the ignition timing and you will get detonation on boost. Ideally you should fit an FCD which limits output from the sensor to just below fuel cut. I do know a couple of cars which are using a 4.7V zener (pennies) direct on the sensor output to achieve this, both have been running for years with no issue. E.g. BZX79C4V7 http://uk.rs-online.com/web/p/zener-diodes/5443575/

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If at first you don't suck seed, try drier grain.

This is EPC fig 17 08 vacuum piping from for a JDM ST185 (non EGR)




hth

If you disconnect the MAP / boost pressure sensor you will NOT have any fuel cut!

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ST165 turbo 4WD
ST185 GT-FOUR RC Carlos Sainz Limited Edition 825•5000
ST185 turbo 4WD Carlos Sainz Limited Edition 2541•5000