Turbo Pressure Sensor

sbart83

New member
yes that is correct. i think throttle position sensor when i see or hear TPS.
the turbo pressure sensor is the unit that the bottom green arrow is pointing to. it does say something like "turbo pressure assembly". IIRC it's a greenish label. top arrow points to the 2 vacuum hoses that go to the a/c idle up valve, center firewall as described above.
 

built2run

New member
it also takes a baro reading just b4 cranking so there are 3 functions of the MAP sensor; it has nothing to do with the A/C
 

Rallly

New member
91 Celica AllTrac oem turbo

After disconnecting the rubber hose(blocking it with a bolt) that goes to the turbo pressure sensor, my fuel cut has been gone, YAY:)
With the nipple capped on the sensor side my oem boost gauge is always showing MAX boost in my gauge cluster.

With the nipple NOT capped, oem boost gauge goes up and stays at 1/4.

Car seems fine both ways but I wonder if with it capped showing full boost on cluster if this will alter what the ecu does with fueling?

Any ideas?




erolit":2jialfp5 said:
TPS = Turbo pressure sensor. on the st185 it provides a pressure signal to the ECU from which the ECU calculates fuel cut. It also has a separate wire connecting it to the stock boost gauge on the dash board.

Appart from these 2 functions it serves no other purpose. There is no pressure sensor based fuel/ignition corrections on an st185 ECU.

If you electronically disconnect it from your engine (ie you cut the PIM wire, unplug the sensor wiring harness etc.) the ecu will begin to calculate fuel cut based on the signal from your AFM & throttle position, and when you hit airflow based fuel cut you have to reset your ECU (by pulling a battery terminal). Basically dont do it.

It will also (by some means which i have yet to establish) pull ignition timing much more readily with the sensor electronically disconnected.

If you want to kill fuel cut, the best way to do is is to unplug the vacuum line from the TPS, and leave everything as it is. This is 100% effective with zero side effects (except for complete absence of pressure related fuel cut)

Elliott
 

freddie

New member
Hey Brian, thanks, you have explained a mystery I have had. I have a JDM 165. No Turbo Pressure Sensor and no factory Boost Gauge (just a green light.)
I have always wondered what controls fuel cut. Now I know, the AFM. The green boost light must be activated the same way. Now all the pieces fall into place.
When I did a little mod. putting a direct air pipe/duct from the AFM to the turbo inlet and installing a hi-flow air filter, the turbo pressure went from 10psi to fuel cut which is 12psi and the engine runs better. The improvement was not so much as to air flow to the turbo, but the reading the AFM provides to the ECU.

It is going to be a bummer hooking up the AC when I put the 205 engine in lol.

Freddie
 
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