Throttle Position Sensor

Hi Guys

i am still trying to trace the small but annoying habit my GTA has of running a bit rough at low revs & snatching on the over run. I have changed just about everything to do with the ignition & fuel supply.

I have had the car out for a run today & when i got back i decided to take another look. With the engine idling I disconnected the TPS lead at the grey 3 pin plug, There was no change to the way the car idled. I reconnected the plug & noting the position of the sensor, rotated it slightly. Again no change. I did note that it was adjusted almost to the max clockwise.

Can these be tested ? Is it worth replacing anyway ? & are they easy to get?

Thanks, Paul

[mettersl]

Isn't this one of the differences between a GTA and an A610?
In the A610 it is a linear TPS and gives a range of readings but on the GTA it's just a switch, the manual calls it a no load/full load switch.
Sorry, I don't have a GTA wiring diagram.
It does sound like the switches aren't working, but there are many here that know the Turbo better than me.

Hi Metters, thanks for that. It makes sense that the sensor is merely a switch, however it still leaves the question of adjustability. If it is a simple switch, why bother being able to adjust it?

Thanks, Paul

[mettersl]

You've got me there, the Renault manual doesn't talk about adjustment at all, it's just says remove and put back....as part of the throttle body.
It's a 77 01 133 623 and its used on the GTA and R25 only (presumably Turbo). It's shown as not available on the Renault system , but it's probably worth a call to your local dealer.
Looks like it has two switches, so unplugging it and measuring connections with a multimeter shouldn't be too difficult. You'll then be able to find out roughly when the switches open or make, it might be miles from your misfire spot.
looks like each of them connect to earth(centre connection) when they are made, seems to be idle and full throttle to make a connection, should be easy to check with a meter.
If you can get one it might be worth changing it if there any doubt? It's 031028 at simon autos..but they don't seem to have any stock. best try MVS or Rats.
Cheers
Lee ( not Clee)

It is a 3 position switch.
It detects idle, when there is no throttle, and Full throttle when wide open, and otherwise it then knows it it part throttle.
I no longer use mine, so it is a spare for sale? No idea what they are worth, but you could borrow it for testing if you wish?

Hi Simon, that's interesting thanks. How do you not use yours ? is the car modified or is it just not necessary ?

I have been out & checked it with a meter. there's no change, so I'm guessing its faulty. Could well be the problem.

Paul

I am running an Adaptronic (after market) ECU and changed the 3 position sensor for a linear rotary 0-100% sensor.

Thanks Simon. I have sent you a pm

Paul

I could be wrong but I think I'd you take them apart anyway they're just standard micro-switches inside the casing.

I could be wrong but I think I'd you take them apart anyway they're just standard micro-switches inside the casing.

hi Darren

Thanks for that. I have carefully taken it apart. The micro switch that operates at idle is not working. So as the revs rise, there is no change, hopefully I have found the problem

Paul

Cool, well done that man.

I think you can swap them out fairly easily, but it's a long while since I've looked at one. If Simon doesn't come up trumps then that's hopefully an option.

IMG_1130.JPG

I went to Maplins at the weekend. Bought a new micro switch for £2.50. It fitted straight in, with a slight adjustment to the wiring. 10 minute job, then back on the car & out for a run.

The car is running MUCH better. The shunting & snatching on the over-run is cured. However it is still a bit rough coming off idle. To be fair this is only noticeable from inside the car. Could the engine or gearbox mounts be failing (hardening) and be transmitting the harshness into the car ?

Link to a video of the engine running now. https://www.youtube.com/watch?v=GmO1wzJ ... e=youtu.be

Paul

.

IMG_1133.JPG

.
Paul, well done, nice work.

Incidently is this an early car? I rather suspect you have an early version of the ecu calibration as well. If you pop the lid off the ecu, and take a picture of the white label on the 20 pin chip furthest side from the ecu connector, roughly middle edge of the board. I expect it will be something like 1xx, 2xx series than the later 3xx, 5xx, 6xx series numbers....

Regards,
Martin

Martin

Yes its an early car. Registered September 1986,

Regards Paul