HDi 110 idle speed running high

[Welly]

Over the last few days my idle speed has increased to just over 1000 rpm when it's normally just over the 750 mark. It doesn't sound much but for a Diesel it is and it makes the car surge a bit in traffic.

Any ideas? otherwise the car runs fine.

Welly

[puggy]

welly i had the exact same problem a couple of weeks ago, idle suddenly
lifted to around the 1k mark and yes bloody annoying. Had a look under
the bonnet at the cable and it seemed fine then i wiggled the wire plug
that goes into the throttle potentiometer or whatever its called , you know
the thing the throttle cable goes to and it dropped and has not done it again

[Welly]

Cool - I'll have a look.

Cheers Puggy

[eoin27]

And if that doesnt work, replace the air filter (or at least take it out and give it a few smacks on the wall) thats what was wrong with mine when it was revving at about 1,000 R.P.M

[Welly]

Thank you puggy - you were spot on

I wiggled the throttle sensor wire and the revs dropped down instantly. What a silly thing

Cheers fella

[puggy]

glad it helped welly now i been useful too

[Welly]

I also 'cleaned' the MAF and WOW!!! throttle response mucho improved - it was feeling a bit flat at low revs but now it has perked up noticeably (and free to).

I also fixed the Air Bag light - I had been wiggling the wrong connector I fished out and unplugged the Pre-Tens connector and bent slightly the connecting pins inside to make a better connection and the light is out for now have you ever seen how many wires you get under the electric seat?

[puggy]

what did you clean it out with welly ? methinks am going to do mine

[Welly]

I unplugged it and removed it with the airbox lid attached - I then carefully dabbed/wiped the wire conducting strips inside with cotton buds dipped in petrol (I suppose you should use some special stuff?) anyway loads of black crap came off the conducting strips and the throttle response is crisp now.

[teamster1975]

Well done that man! It's funny how curing one problem puts you in the mood to sort everything else out

[rapport25]

Have never cleaned mine but here people mentioning them all the time on here. I think its something worth looking at can you put some pics on please welly?. Could you use white spirit or acetone to clean it with?

[Welly]

Have never cleaned mine but here people mentioning them all the time on here. I think its something worth looking at can you put some pics on please welly?. Could you use white spirit or acetone to clean it with?

You literally remove the airbox lid and one jubillee clip on the flexi hose downstream and pull the lid away with the AFM attached (unplug it first) - then you will see a bulb sensor with 2-wires and the 2 conducting metal strips - all of which were dabbed and gently wiped - I suppose electrical cntact ceaner is best but maybe meths/petrol - some spirit which evaporates quickly with no residue - I don't think White Spirit is good as it's a bit oily.

My AFM is a Siemens unit.

[rapport25]

Thanks welly not had much hands on experience with hdi engines. Will have a look at the weekend

[jameslxdt]

i wouldnt recommend cleaning an AFM, they are extremley delicate and do self-clean after you have switched the engine off

[rapport25]

Ok james will leave well alone