Mercedes E270CDI - Ticking Like Clock ....when engine on and off???

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Tue 14 Feb 2012 11:15
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Merc Maiden

I'm looking after my Dad's pride-and-joy Mercedes E270CDI 53 plate. He is terminally ill but has hopes of driving it again one day.I've driven it for 3mths with no problems. After a speedy 12 mile run across fast country roads on Saturday to my parents, on my return journey I experienced loss of power...foot down flat but only got to 30mph. After stopping and restarting all was fine. Now notice a loud intermittent ticking noise from engine - just like a clock - when i drive it. Last night the car made the same noise when switched off and parked on my drive. I've unplugged the battery to stop it. Could it be related to the car alarm? At times when ticking there is also a muted occasional blast of alarm siren! Would be so grateful for any advice as i don't want to worry my Dad at the moment. Thanks

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Tue 14 Feb 2012 11:58
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - cws

Just a guess...........could it be something to do with the air-con system? VW Passats (98-05) suffer with the faliure of the motor that closes the flap when the blowers are set to re-circ, and this manifests itself with a constant tick-tick-tick sound as the motor tries to work but is failing.

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Tue 14 Feb 2012 13:20
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Merc Maiden

cws, thanks for your reply. I hadn't thought of that but seems plausible. The air-con is set at AUTO all the time..i haven't changed anything since have been driving it. The car has been regularly serviced and no probs since new and now all this happens,grr! Do you or anyone else know if this would be a massively expensive fix? Or any ideas on what else it may be if not air-con?

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Tue 14 Feb 2012 14:00
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - cws

Without spending any money, I think the best next step may be to find a mercedes forum, and post your question on there, in the relevant section. Hopefully you'll find someone with more knowledge on there, as my guess could be way off the mark.

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Tue 14 Feb 2012 15:10
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - madf

Known fault with aircon motors used to adjust vents failing to operate correctly and ticking away.

Much dismantling required.

Edited by madf on 14/02/2012 at 15:10

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Tue 14 Feb 2012 16:06
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Merc Maiden

Many thanks for these further replies. I'll have to get it into a garage then.

Sorry if this sounds obvious but is the car ok to drive until then?

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Tue 14 Feb 2012 18:17
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - elekie&a/c doctor

A fault with the heating flaps is not going to cause the car to drive at a max of 30mph.Get an engine diagnostic check done to establish if there is anything logged that may cause a lack of power.If there are no red warning lights showing on the dash,then it should be ok to drive.hth

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Tue 14 Feb 2012 22:36
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Collos25

It appears to have dropped into LHM normal problem is the EGR valve could be the solonoid of this valve you can hear,also they have two batteries a small battery is situated under the plastic cover under the bonnet on the left hand side this is used for many things including running the heater and ac when everything is switched off there is push button on the dashboard for called rest heat which activates this program.

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Wed 15 Feb 2012 08:33
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Collos25

Just a thought have you accidentlly put the speed limiter on.

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Wed 15 Feb 2012 09:25
Mercedes E270CDI - Ticking Like Clock ....when engine on and off??? - Merc Maiden
Thank you for those replies. I don't think i accidentally switched anything on, or off, I've been so careful when driving it! No warning lights came on. Will have a peer under the bonnet for the small battery. It looks like I'm going to have to bite the bullet and take it in to a MB garage....much £££££s i guess....
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