2001 Throttle housing.. does it require calibration??

[antd]

clio 2.2 d7f engine 2001

Ok long question...

I had the head gasket go...
Had it replaced... Twice (even longer story)

But since then the car has idled poorly....

redid the tappets... checked everything ...
cleaned the throttle housing...

Still rough

Then ran a diognostic.... (borrowed snapon tester)
The throttle was showing that it is at 15% when idle.....

So thinking that this is not normal, I tried the diognostic tester on an astra
this showed the throttle at idle was O%

Is this normal, or is this likely to be the source of the notorious clio poor idling fault??
Or is this calibrated on the car by renault??

Any help or comments would be gratfully recieved...

 

[Jonny1*2]

It should be a 0% at idle mate. Is the throttle sticking open or it may be the tps itself

 

[antd]

It should be a 0% at idle mate. Is the throttle sticking open or it may be the tps itself

Thanks for the reply...
The throttle is clean and closed...
I even wound the idle adjust screw back to see if that took the reading back (it didnt)

The throtle potentiometer is inline with the butterfly valve so I find it very unusuall that the reading is not zero.

I thought that perhaps as this was just a resistance reading, it could be calibrated to say that at this resistance the throttle is closed....

I wonder if this is common on old clio's ?

 

[Jonny1*2]

Could you not get a spare tps to check it?

 

[Ben182trophy]

When you say rough idle? Misfire, hunting? Revs up an down? If the head has bin off (twice) might be worth checkin for air leaks maybe?

 

[antd]

Could you not get a spare tps to check it?

The throttle housing on this engine has fixed tps and other sensors (cant be removed) you have to buy the complete housing....
Looks like ebay as renault charge £230 for the part

 

[antd]

When you say rough idle? Misfire, hunting? Revs up an down? If the head has bin off (twice) might be worth checkin for air leaks maybe?

Just an ocasional judder at idling...
I have changed the plug leads coil and plugs....
So it seams unlikely that it is an ignition problem

But if the tps is saying the throttle is at 15%, and the ecu is reading that the revs are low this would confuse the ecu....

After the number of post I have seen about rough idling I am begining to think this may be the problem with many older 1.2's

 

[Fred@BTM]

It should be a 0% at idle mate. Is the throttle sticking open or it may be the tps itself

no 0% would mean the engine wouldn't run

 

[antd]

no 0% would mean the engine wouldn't run

No it think he's right.
We tried the tester on an astra and at idle the throttle was at 0%

I'm just not sure as to whether the 15% means the throttle sensor is out or whether the setting is programmable and out on the ECU

 

[Ben182trophy]

Trying it on a vauxhall is no good as it will work differently to a Renault, at idle I think mine reads about 17% on my 182

 

[MicKPM]

On a throttle cable setup maybe but on a stepper controlled throttle 0% throttle at idle would not happen as Fred said above because that would indicate the throttle plate was actually closed shut (which requires motor effort to achieve).

When initialising the adaptives, the natural "rest" position is normally 5-8% advance (it varies slightly between TB types) so you'd expect to see (at true idle at least) a fluctuating value of at least this as the throttle plate, on current Renault platforms at least, also controls the idle speed which it does by advancing/retarding the throttle plate angle.

Mick