Car vibrating when idle

PraxxtorCruel · 26 Jun 2016 at 18:22

The car in question is a Ford C-MAX 2.0 diesel that vibrates when idle. As soon as the gas pedal is pushed in it disappears. Releasing or engaging the clutch in makes no difference. Although one weird thing is when you drive it for a bit, it eventually stops vibrating at idle. I've also found that if the car is left untouched for a few days it can be a slight struggle to get it to start. It starts but it feels like it's struggling to ignite. Drive it around for a bit and all these symptoms disappear. What could be causing the vibrating issue? I started thinking it might be a failing battery?

Any ideas?

Thanks!

p1RATE · 26 Jun 2016 at 18:36

Sounds like an idle issue which could be a few things. Where are the cars rev's at idle do they surge at all?

PraxxtorCruel · 26 Jun 2016 at 18:37

p1RATE said:
Sounds like an idle issue which could be a few things. Where are the cars rev's at idle do they surge at all?

The revs at idle are stable. Hovering at 800 or 900 I think.

[TW]Fox · 26 Jun 2016 at 19:48

It's a 4 cylinder diesel, surely they all vibrate when idle? It's one of the annoying things about them.

Ryan-3 · 26 Jun 2016 at 19:52

Not sure how a failing battery would cause any vibration? Plus, once the car is running it is running from the alternator unless that's failing.. forget it for this fault.

Idling slightly more rough than normal? As Fox says, it is a 4 pot diesel engine, they're not that smooth.

breadturbo · 26 Jun 2016 at 20:04

If it's a mk1 the pug diesels do this when the dmf is on the way out, you may also hear a slight rattle on idle if you stick your head near the gearbox.

grudas · 26 Jun 2016 at 20:12

Is the engine on by any chance?

andy_mk3 · 26 Jun 2016 at 20:21

Injectors are very common on them. Although without a proper diagnosis anything is a stab in the dark really.

Nasher · 26 Jun 2016 at 20:27

How many miles has it done? Could just need the injectors cleaning maybe.

jpaul · 26 Jun 2016 at 20:38

with an older petrol bmw had the same symptoms - there was an air leak, between air metering system and engine due to crack in the rubber hosing (which i fixed with self amalgamating tape)

Janesy B · 26 Jun 2016 at 22:41

When you start it the idle is slightly higher than normal, so you might get a bit of vibration caused by resonance. After driving for a while and the engine is warm the idle will be slightly lower and won't give the vibration.

The car doesn't have a problem. If you want better NVH performance, don't buy a diesel Ford

blueboy2001 · 26 Jun 2016 at 23:52

It's probably an injector failing due to worn nozzles. Often shows itself at idle with little fuel throughput and the vibration is actually due to the engine running on 3 cylinders.

Have an injector leak off test done initially and go from there. I'd suggest going to a diesel fuel injection specialist rather than a general garage for this as they have the proper kit for testing and repairing injectors.

Akagi · 27 Jun 2016 at 02:17

[TW]Fox;29695419 said:
It's a 4 cylinder diesel, surely they all vibrate when idle? It's one of the annoying things about them.

grudas said:
Is the engine on by any chance?

It is pretty obvious that the OP means an unusual vibration at idle... I've never sat in a diesel which vibrates noticeably when idle anyway... Aside from a burgundy Citroen Xantia.

Could be an engine mount, just to add to the other suggestions. If the rubber has worn badly it could cause unpleasant juddering.

FuriousGeorge · 27 Jun 2016 at 14:23

edit just reread the OP so ignore!

SC0TTRS · 27 Jun 2016 at 14:28

EGR Valve needs cleaning or replacing.