Lumpy/holding back before upto temp

[Faboka]

Over the past few months I've noticed a lumpy (more than normal) idle and also very hesitant at low revs. Only lasts for about a minute or so then it's like a switch has just been flicked and then it's back to normal.

Any ideas?

Have noticed every now and then it doesn't fire up on the first crank. But second is fine. Take it this is the CAS sensor? If so could this cause the hesitant as well?

Thanks

 

[Faboka]

Started second time this morning. Gave it a couple of blips and it was missfiring. Once you drive it a little it's fine.

I know the lumpy idle is normal but surly the misfire isn't?

 

[Dunn]

pre cat lambda

makes it run odd when cold then once warmed up it will be fine

can sometimes feel like its accelerating slightly by itself and be hesitant when cold

EDIT: misfire wouldnt really relate to lambda, but original symptoms do. i would pay £35 at a specialist for diagnostics

 

[d4vy]

Mines exactly the same, had the pre-cat lamba replaced and made sweet all difference, quite horrible to drive before temperature!

People say it's normal but I can't see how it being as bad as what mine is, as being normal.

 

[d4vy]

Be interesting to see what comes of this, mine also doesn't always start first time.

 

[olliewebbuk]

Yeah, get the codes read. Could possibly be the TDC too?

 

[MicKPM]

It'll be the H02 sensor for sure... most liekly the heater element starting to give up. It might not actually give any fault codes though so don't pay for someone to read the codes and say "Nowt wrong with it" as it will need a trained eye looking at the H02 live data to finger.

 

[d4vy]

It'll be the H02 sensor for sure... most liekly the heater element starting to give up. It might not actually give any fault codes though so don't pay for someone to read the codes and say "Nowt wrong with it" as it will need a trained eye looking at the H02 live data to finger.

Hate to steal the topic - but had my o2 sensor changed and didn't fix the problem.

The fault did come up in the system saying it was faulty, however.

 

[MicKPM]

And that's why you never rely upon fault codes... always confirm the fault with Live data and actual component testing.

Proberbly a wiring fault on that circuit causing the fault code to come up with faulty sensor.

 

[d4vy]

And that's why you never rely upon fault codes... always confirm the fault with Live data and actual component testing.

Proberbly a wiring fault on that circuit causing the fault code to come up with faulty sensor.

I didn't go entirely with the fault code, just what I was advised by people + on here.

To be fair to the advice given on here, changing the o2 sensor did generally cure the problem for most people.

Edit: Infact I brought the o2 sensor before even checking the fault codes lol.

 

[Faboka]

Thanks for the replies. Will a normal hand held fault code reader work? Or do you need a CLIP?

Is their anyway of testing the 02 sensor?

 

[olliewebbuk]

CLIP is recommended.

 

[Faboka]

Could I just swap the pre and post lambda sensor around to see if it improves?

 

[Faboka]

thanks

 

[Faboka]

Well this is now fixed. It was the exhaust blowing at the join of the car to centre section.