Megane Rough idle

[Ryanbrown]

when my car is idle it runs not consistent and vibrates, car runs fine when drive and reved, any ideas? Sensor?

Ps sorry for beeb busy body posting all time but this forum is only one that I seem to get answers from!

 

[andybond]

Post away. Love to help.

Do the revs "bounce" ? Say between 750 and 1400 ?

Does it cough out of the exhaust , sort of normal , cough , normal ?

 

[Ryanbrown]

Yeah abit!

 

[DaveL485]

Bond is vibration not symptomatic of DMF?

 

[andybond]

No , DMF failure is normally a clunk , or sounds like vibration but never feel it.

I reckon mucky injectors and / or knackered engine mount

 

[andybond]

 

[andybond]

 

[Ryanbrown]

Hmm isn't that bad can't really hear anything just vibrating In the car, I'll probally just take it to a garage

 

[andybond]

In that case Ill revise my ideas and say its the back left mount. Known for failing !

 

[Ryanbrown]

Cheap fix?

 

[andybond]

£100 odd ..

 

[DaveL485]

£100 odd ..

Anything under 4 figures counts as "Cheap" now lol

 

[Brigsy]

Vibration on idle will most likely be the top engine mount. If its coughing out of the exhaust the injectors will need refurb/replace - injectors are well worth doing for the mpg increase.

Both common issues on the meg...both easy fixes. Half hour for the mount - half hour to change injectors.

 

[Ryanbrown]

How much we talken for both fixed, much appreciate all the advice and help!

 

[andybond]

Standard injectors are £160 new from renault.
You can get them ultrasonically cleaned for around £60
Where abouts are you in the UK , Ill change injectors if you are stuck.

 

[Brigsy]

Top engine mount was about £50-60 from euro car parts.

 

[andybond]

Vibratech on is 100+vat I think .

 

[Brigsy]

The vibratechnics one might be a bit much for a road car. Vibrate like feck

 

[slgreavett]

Can identify injectors generally by gently clamping the fuel return line after the regulator, if you have one!some efi don't even run return. This increases pressure and helps push the fuel past the crap/water etc if the engine smooths out you know your injectors are dirty/blocked. This does not tell you your injector coil condition, so you will need an oscilloscope to measure the pattern for that.
Injector flow testing, back flushing and ultrasonic bathing is the best way, which means removal. But again that won't fix a weak/faulty injector coil.

 

[andybond]

I dont think there is a fuel return line on the megs.