Refuses to idle.. TPS?

[Jhonno]

Right.. Cerbera refuses to idle. I can't drive it till it is sorted now. As soon as you remove throttle it dies. My diagnostics won't talk to my ecu..

Lambdas are nearly new.. Checked in the right side as well. Plus disconnecting the ECU did nothing.

TPS' - I have measured the resistance range across them.

Drivers
0.598 kohms
2.967 kohms

Passengers
0.711 kohms
3.466 kohms


Now to me that seems like one has died/failing?

My throttles were setup fine previous, can I replace the TPS' and it'll work ok? Or does it definitely have to be setup each time? This is a sudden failure.. Was fine, parked up, then refused to idle.

Edited by Jhonno on Sunday 11th August 23:44

Edited by Jhonno on Sunday 11th August 23:45

[Jhonno]

MG 25 ZR throttle pots according to the parts list.. Which are £90 each from ECP! Or £30 from TVR Power?! Or £15 on eBay? Is there such thing as a good/bad quality tps?

[QBee]

On a Chimaera a stepper motor controls the idle. Don't know what controls it n a Cerbera.
I had no idle when hot on my Chimaera. The stepper had become temperature sensitive. Change of stepper cured it.

[Tanguero]

If you replace the TPS you will definitely need to get the diagnostic software working to set it up. You can't just stick it on and hope for the best, it is not going to be balanced with the other bank and will most likely run no better than it is now.

What is the problem you are having with the diagnostics? Its not usually that much of a problem to get working and is the only way to solve problems like this.

[Tanguero]

QBee said:

On a Chimaera a stepper motor controls the idle. Don't know what controls it n a Cerbera.
I had no idle when hot on my Chimaera. The stepper had become temperature sensitive. Change of stepper cured it.

No stepper motor on an AJP8

[cshaw4200]

Hi i adjusted my throttle pots 2 months ago with gunsons colortune worked fine before running rich on tickover and would like to stall when cold fine now

[Jhonno]

Tanguero said:

If you replace the TPS you will definitely need to get the diagnostic software working to set it up. You can't just stick it on and hope for the best, it is not going to be balanced with the other bank and will most likely run no better than it is now.

What is the problem you are having with the diagnostics? Its not usually that much of a problem to get working and is the only way to solve problems like this.

Fair enough.. Wasn't sure, I know the mechanical side of it was setup, and was working, I just wasn't sure if you could then put a new tps on as it is just a linear change in resistance. The fact (one?) of mine is not makes me think failure.

My diagnostics is:

Win7 32bit
USB to serial adapter (FTDI chipset)
Com 1
New diagnostic software
Tried all the Baud rates.

Software recognises the adapter as being on Com1 etc just getting nothing back from the ECU.. Light on the adapter says it is trying to talk to it.

Need this sorted by Sat! Got a little jaunt for it..

[Jhonno]

I have a desktop PC with a serial port on it.. Might have to move that into the garage..

[SlvrCrb]

Jhonno said:

Software recognises the adapter as being on Com1 etc just getting nothing back from the ECU.. Light on the adapter says it is trying to talk to it.

Need this sorted by Sat! Got a little jaunt for it..

Any time I've had problems with the ECU talking to the software, I've fired things up in the following order and it's finally worked

1. With everything off connect the serial>usb lead between ECU and PC
2. Without disabling immobiliser hit the red button (so you get all lights on the dash bar the MIL)
3. Start the laptop, let it boot and then fire up the software. It should say 'ECU not connected'.
4. Press the fob to engage the ECU/Fuel Pump. Software should show a screen full of data.
5. Start the car.

hth.

[Jhonno]

I do have a 3 pin connector coming from the ecu also.. Would this also work for diagnostics?

[SlvrCrb]

There's a write up on using the 3 pin connecter here.

[QBee]

Tanguero said:

QBee said:

On a Chimaera a stepper motor controls the idle. Don't know what controls it n a Cerbera.
I had no idle when hot on my Chimaera. The stepper had become temperature sensitive. Change of stepper cured it.

No stepper motor on an AJP8

Wrong again........never mind

[Jhonno]

SlvrCrb said:

Jhonno said:

Software recognises the adapter as being on Com1 etc just getting nothing back from the ECU.. Light on the adapter says it is trying to talk to it.

Need this sorted by Sat! Got a little jaunt for it..

Any time I've had problems with the ECU talking to the software, I've fired things up in the following order and it's finally worked

1. With everything off connect the serial>usb lead between ECU and PC
2. Without disabling immobiliser hit the red button (so you get all lights on the dash bar the MIL)
3. Start the laptop, let it boot and then fire up the software. It should say 'ECU not connected'.
4. Press the fob to engage the ECU/Fuel Pump. Software should show a screen full of data.
5. Start the car.

hth.

Missed this.. Can try this.

[Jhonno]

SlvrCrb said:

There's a write up on using the 3 pin connecter here.

Wish I had realised before I can use this! Got confused with the redundant 2 pin from later models. I would have made a lead up already!!

• My understanding was that it was a late model only thing..

Edited by Jhonno on Monday 12th August 10:04

[TimJM]

Didn't Aide knock up an android version? If you have an android phone or tablet would it be easier to connect that up?

[Jhonno]

TimJM said:

Didn't Aide knock up an android version? If you have an android phone or tablet would it be easier to connect that up?

He has. It isn't released yet..

[Tanguero]

cshaw4200 said:

Hi i adjusted my throttle pots 2 months ago with gunsons colortune worked fine...

[Jhonno]

My attempts to get the diagnostics to work.. Desktop PC running XP and serial ports.



Yes that is a Tuscan mouse..

[HarryW]

Jhonno said:

My attempts to get the diagnostics to work.. Desktop PC running XP and serial ports.



Yes that is a Tuscan mouse..

That picture has made me smile, never thought I'd see a full tower PC used as a portable. Anyway I see the problem, your mouse mat is a bit lumpy......

[Jhonno]

It got dropped into Kerridges TVR as I was lacking time to source/sort this week for using it on Sat.

It was the Throttle setup.. It was noted that neither TPS was running smoothly/giving smooth traces, so 2 new TPS's required for a complete fix. Will get it back Friday.