Warm missfire again

[Iain C]

So my cup has been off the road a year and a half partly because of a missfire when warm. Runs fine from cold. It will usually run for 25 min before the failure.
So far I've replaced
Leads
Coil pack
Plugs
Injectors
Engine sensor
O2 sensor
No errors showing
Anyone got amy ideas. Cos I'm out!
Ta

 

[JamesBryan]

Coolant temp sensor?

 

[dann2707]

TDC sensor or is that the engine sensor you've said?

 

[R3k1355]

All genuine Renault items as well??

No errors showing

Scanning with what??

 

[Iain C]

Yeah tdc sensor has been changed.
Coolant temp sensor hasn't been changed. I did think that actually. Maybe worth a change.
All Renault items or uprated.
My scanner isn't the best just a basic reader.
Ta

 

[R3k1355]

Do the coolant temp sensor, and see if you can find someone with Clip.

 

[Rone]

It will usually run for 25 min before the failurea

Sounds like a sensor failure in the engine compartment due to radiant heat from the engine block.
I would not bet on the coolant temperature sensor, as the car should reach running temperature in the coolant in less than 10 minutes.
25 minutes sounds more like a problem in the throttle body / TPS sensor receiving heat and getting a dysfunction.
But let us see how the new CTS affect the fault first...

 

[Iain C]

Thanks rone. I didn't think of the throttle body being an issue.
I've got a genuine cts on order at the mo so will try that first. Ta

 

[Iain C]

Ok new cts fitted and the problem us still there. Grrr :rage:

 

[STEVE.M]

Ok new cts fitted and the problem us still there. Grrr :rage:

You could check the vacuum hoses for the carbon canister & acoustic valve for an air leak.
Just remove the hoses from the inlet manifold & cap the spouts,one at a time.

 

[Iain C]

Would a vac problem cause a missfire?
Ta

 

[STEVE.M]

Would a vac problem cause a missfire?
Ta

Weak mixture,incorrect MAP sensor readings,lots of fun.
Canister takeoff at RH(cambelt) end of inlet manifold,acoustic at front by the throttle body.

 

[Iain C]

Weak mixture,incorrect MAP sensor readings,lots of fun.
Canister takeoff at RH(cambelt) end of inlet manifold,acoustic at front by the throttle body.

Ok mate ta. I'll try that.

 

[bloke]

if it was a vac leak it would be there all the time. get it plugged in with something decent and look at live data.