2001 D4D Fast, Erratic Idling

[TRB]

Hi all. Have had our 2001 2 litre diesel estate for a few months now. Good as gold until recently when the tickover became erratic. From cold start, goes to around 1100. As it warms up, it either stays at 1100 or sometimes goes to 1250 or 1300. It does eventually drop down to 7-800 but only when engine fully warmed - more than 15 miles normal driving. Previously ticked over at 750 rpm all the time.

I've replaced the air filter and removed the EGR valve and cleaned it (thanks Rossi 46 for the guide) and yes, I used a new gasket when replacing it. All normal servicing up to spec. Currently on 86,000 miles so only just run in! Anyone able to help? Oh and fuel consumption is averaging 30mpg at best but that is mostly town driving.

[igormus]

check with MAF sensor - it must be dirty giving a wrong signal to ECU

cheers

[Auris sr 180]

If u have your blower on hot it will jack the revs up to Plus with lights dimister fan all on the alternator will be under load and will rev up slightly to compansate

[TRB]

Thanks for the replies. Regarding the MAF sensor. Is that the thing in the air filter box? Can I clean it with brake cleaner or do you need something more specialised? As for load on engine, have only had heater blower on low, no rear window demister, no lights and tickover still very high/erratic.

[jedi134]

Do you have an idle up button?

[Mistermena]

Thanks for the replies. Regarding the MAF sensor. Is that the thing in the air filter box? Can I clean it with brake cleaner or do you need something more specialised? As for load on engine, have only had heater blower on low, no rear window demister, no lights and tickover still very high/erratic.

I wouldn't use brake cleaner on it! get some electrical contact spray or better still there is a product called CRC thats you can buy off eBay for £10 ish!... But contact spray is about £3 from maplins ect

[TRB]

Thanks for the replies. Idle up button? Never seen one. I'll try the contact cleaner spray on the MAF sensor for starters. Cheers.

[igormus]

the idea is to have clean MAF sensor sensitive element contact with suction air to have correct signal to the ECU.

cheers/Igor

[Jas16]

What you say seems entirely normal. This setting kicks in when it detects the outside temp to be 10 degrees C or below

Don't worry, it's a setting to get your engine up to temp as quick as possible. And to fully get up to temp takes a while too, same with mine. It did take me by surprise last year when I first got the car, but its normal

[TRB]

Thanks for this Jas. I'll give the MAF a clean anyway - nothing to lose, but it's good to hear that others have the same symptoms.