Throttle pot noise

[Tanguero]

When I recently replaces a throttle pot on my 4.2 I noticed that when I had the laptop hooked up to adjust it I was getting what looked like a noisy signal. The reading on that bank was jittering up and down by +/- 0.2 while the other bank was rock steady. Interestingly when I switched the wires around the noise moved with the wire implying that it was not a problem with the new throttle pot.

Doesn anyone have a view as towether this is indicative of a problem that needs sorting - or just one of those TVR things?

Curiously I have been getting an fault logged for the bank 1 lambda sensor. Apart from a reluctance to idle while hot, there hasn't been any noticable bad running and the values on the screen seemed to be comparable with the other sensor. Related? Or really time for a new lambda sensor?

[WIL35]

I have always had the same symptom on one of my throttle pots. Checked it the other day and one was flicking between 14.4 and 14.8 when the engine wasn't running, the other one was stable on 14.8.

[methodwares]

WIL35 said:

I have always had the same symptom on one of my throttle pots. Checked it the other day and one was flicking between 14.4 and 14.8 when the engine wasn't running, the other one was stable on 14.8.

that's a bit low, thought 15 was with the idle screw backed all the way off

[WIL35]

methodwares said:

WIL35 said:

I have always had the same symptom on one of my throttle pots. Checked it the other day and one was flicking between 14.4 and 14.8 when the engine wasn't running, the other one was stable on 14.8.

that's a bit low, thought 15 was with the idle screw backed all the way off

I did wonder about that after reading a couple of recent threads. Trouble is, it 'seems' to be running ok, so I am reluctant to start adjusting things then regretting it.

If I just adjust the pots to around 17, what is that telling the ECU?

[marcus1970]

WIL35 said:

methodwares said:

WIL35 said:

I have always had the same symptom on one of my throttle pots. Checked it the other day and one was flicking between 14.4 and 14.8 when the engine wasn't running, the other one was stable on 14.8.

that's a bit low, thought 15 was with the idle screw backed all the way off

I did wonder about that after reading a couple of recent threads. Trouble is, it 'seems' to be running ok, so I am reluctant to start adjusting things then regretting it.

If I just adjust the pots to around 17, what is that telling the ECU?

It's telling the ECU to bung in 17 worth of fuel to go with the air that will be pushing through.

For example, if you're reading 15 say at idle and you pop up the throttle pot to 17 at idle, you will just get more fuel going in with no more air. The trick is trying to get the balance right so that the adaptives are as close to zero as possible.


MB