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Tps Problems

igota33

By igota33,
in Engines & Forced Induction

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igota33 Enthusiast

igota33

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had a problem with car pinging on deceleration. just had a power fc installed and tuned on a dyno. i've had a look at my tps (throttle position sensor) and noticed it has a blank plug connected to it and 3 wires coming out underneath it. is this normal or should the plug on the side of it be connected to something. i think the computer is having trouble with the amount of fuel to put into the motor after heavy boost thus car is leaning out cos it doesn't know where the throotle is at. any ideas?

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blind_elk Grand Master

blind_elk

Posted
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There should be 2 connections - a Throttle Position Switch (tells ECU if throttle closed or WOT) and a Throttle Position Sensor (tells ECU exactly how much throttle).

I have never heard of an engine pinging on deceleration (low load situation). Most EFI engines switch off the injectors on "throttle closed" (in gear changes or full backoff) - if it's going to run lean, then no fuel will do it, but engines don't ping / detonate under these conditions, otherwise manufacturers wouldn't build it in.

Following heavy boost, the air temp is probably too high (even with a FMIC) - check the PFC's air temperature compensation.

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igota33 Enthusiast

igota33

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here is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking for a ride.

here is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

here is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

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igota33 Enthusiast

igota33

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post-26381-1140927794.jpghere is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

sorry about he posts. it's my first time. couldn't figure out how to add attachment

here is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

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rob82 Mentor

rob82

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Posted
post-26381-1140927794.jpghere is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

sorry about he posts. it's my first time. couldn't figure out how to add attachment

here is a picture of my tps. the plug on the side is blank ie. not connected to anything. i don't think this is normal and is causing my problem. my tuner has given my fuel pump constant power because he's 'waiting on a part from japan' and said there was a problem but is ok to drive. he's pretty reputable in adelaide but i think they've either killed the wiring somehow and need to replace it or i have no idea. no connection to my computer from the side plug would not give a throttle position reading? am i correct? i'm a relatively newbie to skylines and think my tuner is taking me for a ride.

Is it actually pinging or is the knock sensor picking up spurious noise. They have two tps as the auto's use one tps for its shift schedualing.

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igota33 Enthusiast

igota33

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took the car to morpowa monday. couldn't have been more helpful. most probably cat converter giving out and sounds similar to pinging as pieces are flying around inside. knock sensor picked up noise as it travelled through ehhaust. no major problem. idle problem sorted. thanks for everyones help. p.s. there is no connection on tps on the side of it. it's for an auto. you were correct. cheers

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JimX Grand Master

JimX

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An easy way to see if it is possibly pinging on deceleration is just keep an eye on the sensor readout for injector duty. It should instantly drop to 0% until you hit the fuel cut off setting (usually around 1000rpm) where it will kick back in so it can idle. If it's at 0%, it can't be pinging because there's no fuel to ping. Unless it's a leaky injector.

This isn't something I would shrug off as "it's probably X being the cause". I've had a rattly cat before and it didn't sound like pinging exactly, and I could tell it was from under the car not the engine. It may well be the cat, but it won't take much effort to double check.

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  • 7 months later...
Cubes Grand Master

Cubes

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And to dig up an old thread.

That plug not being connected.

For those interested after a little investigation..

The R32's.

All the R32's I've seen all have this plug connected with associated wiring. However, they have all been series 2 R32's.

They were are all manuals and one was a GTS4.

The plug is called the throttle valve switch. On the R32's it's connected to ecu pins 57 and 54 and the full throttle contact point runs to the a/t computer. The ECU uses the data from this input to control Fuel injection, Ign. Timing and Idle speed control.

Its interesting to note the R32 PowerFC's (that are based on an R33 RB25 powerfc) have ecu pinout 57 trace cut, as a result no power will be delivered to the top plug so essentially, its useless and doesn't need to be connected.

The reason this trace is cut is the R33's its used for the ecu's exhaust temp sensor signal.

The R32 doesn't run an exh. temp sensor signal to the ecu, the dash and associated crap that goes with it takes care of the exh. temp dash light display.

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