Engine juddering

KevF6 · 16th November 2018, 15:49

I hope someone can help!

I am getting a juddering from the engine, you can feel it almost slightly misfiring at idle and you can see the needle slightly moving up and down. Also when I’m driving it judders at times for example when pulling away and even just cruising at the same speed. It doesn’t do it all the time and is intermittent, sometimes all gears sometimes just one. Basically when I push the accelerator down (even really gently).

It’s really doing my head in not knowing what it is - it almost feels like fuel starvation? I thought it might be the lower engine mount but that was changed today and it’s still the same!

Argh!

gazcaz · 16th November 2018, 16:44

Check your idle control valve ,broken vacuum lines and plugs.mine made a difference when i serviced my idle valve...

KevF6 · 16th November 2018, 18:34

Thanks for the reply!

Would you be able to give a bit more detail as I have no idea what you mean! Sorry for being dim.

Thanks

Kev

Comfortably Numb · 16th November 2018, 18:55

It will be on the air plenum box , near the throttle. It allows a small amount of air to bypass the throttle valve to keep the engine running at idle. Surprised if it would cause those symptoms. Sounds more like failing injector, spark plug(s) or plug lead(s). Start it up in the dark, open the bonnet, and rev it from under the bonnet. See if you can see electrical sparks jumping about. It may tend to be worse in damp, dewy weather.

Comfortably Numb · 16th November 2018, 18:59

PS Sorry. Failing spark due to break down of plug nose insulation would not show under the bonnet, but the plug spark is so weak, the fuel injection drowns it, usually at lower revs with foot down, so the fuel does not ignite properly.

COLVERT · 16th November 2018, 19:41

Crankshaft pulley beginning to fail ?????

Will judder in all gears and revs.

SD1too · 17th November 2018, 07:26

Quote:

Originally Posted by COLVERT

Crankshaft pulley beginning to fail ?

Not on a KV6 Jon. That delight is the preserve of the diesel!

Kev, does your car have a manual gearbox?
Another real possibility is 'fuel filter syndrome'. Do you have the orange clip fitted?

Simon

KevF6 · 17th November 2018, 10:06

Thanks for the replies chaps, it is a manual Simon - what orange clip and where is it lol?

Thanks

Kev

SD1too · 17th November 2018, 13:28

Quote:

Originally Posted by KevF6

... what orange clip and where is it?

It can be fitted to the fuel filter to prevent the two halves of the casing loosening in service. When this happens fuel pressure is reduced and the engine falters or stops. The filter is located under the rear seat cushion on the passenger side. For further reading, search for 'FFS' or 'Fuel filter syndrome'.

Quote:

... it is a manual Simon ..

Thanks. It also occurred to me that your clutch friction plate might need renewing.

Simon

championdaddy · 17th November 2018, 16:47

I too think it is drive train related.

The car still starts great so I doubt the clip is to blame.

Seems to happen under load if you labour the engine ( high gear, low speed)

So I agree with SD1too........... could be fly wheel

16th November 2018, 15:49	#1
KevF6 Loves to post Rover 75 Join Date: Jul 2016 Location: Luton Posts: 354 Thanks: 37 Thanked 89 Times in 70 Posts	Engine juddering I hope someone can help! I am getting a juddering from the engine, you can feel it almost slightly misfiring at idle and you can see the needle slightly moving up and down. Also when I’m driving it judders at times for example when pulling away and even just cruising at the same speed. It doesn’t do it all the time and is intermittent, sometimes all gears sometimes just one. Basically when I push the accelerator down (even really gently). It’s really doing my head in not knowing what it is - it almost feels like fuel starvation? I thought it might be the lower engine mount but that was changed today and it’s still the same! Argh! __________________ [SIGPIC][/SIGPIC] Done: New leather & walnut steering wheel, headlight restore, new badges to rear & engine, walnut facia trims, full size spare wheel, timing belts, Plenum spy hole, DD head unit. • This vehicle was the 67,855th 75 to run off the production line, out of 112,381 • This vehicle was the 2,457th 75 2.5 V6 Connoisseur SE to be made out of 3,671

16th November 2018, 16:44	#2
gazcaz I really should get out more....... MG ZT Join Date: Nov 2014 Location: Worthing Posts: 2,744 Thanks: 3,944 Thanked 576 Times in 471 Posts	Check your idle control valve ,broken vacuum lines and plugs.mine made a difference when i serviced my idle valve... __________________ [SIGPIC][/SIGPIC] MG ZT 2.5 V6 234th of 2,834 Trophy Blue ZT 190 + Saloons Produced 14th of 27 MG ZTs Produced on 27-09-2001

16th November 2018, 18:34	#3
KevF6 Loves to post Rover 75 Join Date: Jul 2016 Location: Luton Posts: 354 Thanks: 37 Thanked 89 Times in 70 Posts	Thanks for the reply! Would you be able to give a bit more detail as I have no idea what you mean! Sorry for being dim. Thanks Kev __________________ [SIGPIC][/SIGPIC] Done: New leather & walnut steering wheel, headlight restore, new badges to rear & engine, walnut facia trims, full size spare wheel, timing belts, Plenum spy hole, DD head unit. • This vehicle was the 67,855th 75 to run off the production line, out of 112,381 • This vehicle was the 2,457th 75 2.5 V6 Connoisseur SE to be made out of 3,671

17th November 2018, 10:06	#8
KevF6 Loves to post Rover 75 Join Date: Jul 2016 Location: Luton Posts: 354 Thanks: 37 Thanked 89 Times in 70 Posts	Thanks for the replies chaps, it is a manual Simon - what orange clip and where is it lol? Thanks Kev __________________ [SIGPIC][/SIGPIC] Done: New leather & walnut steering wheel, headlight restore, new badges to rear & engine, walnut facia trims, full size spare wheel, timing belts, Plenum spy hole, DD head unit. • This vehicle was the 67,855th 75 to run off the production line, out of 112,381 • This vehicle was the 2,457th 75 2.5 V6 Connoisseur SE to be made out of 3,671

16th November 2018, 18:55	#4
Comfortably Numb Posted a thing or two Rover 75 Saloon Join Date: Dec 2017 Location: Penrith Posts: 1,336 Thanks: 165 Thanked 303 Times in 241 Posts	It will be on the air plenum box , near the throttle. It allows a small amount of air to bypass the throttle valve to keep the engine running at idle. Surprised if it would cause those symptoms. Sounds more like failing injector, spark plug(s) or plug lead(s). Start it up in the dark, open the bonnet, and rev it from under the bonnet. See if you can see electrical sparks jumping about. It may tend to be worse in damp, dewy weather.

16th November 2018, 18:59	#5
Comfortably Numb Posted a thing or two Rover 75 Saloon Join Date: Dec 2017 Location: Penrith Posts: 1,336 Thanks: 165 Thanked 303 Times in 241 Posts	PS Sorry. Failing spark due to break down of plug nose insulation would not show under the bonnet, but the plug spark is so weak, the fuel injection drowns it, usually at lower revs with foot down, so the fuel does not ignite properly.

16th November 2018, 19:41	#6
COLVERT This is my second home R75 Saloon. Join Date: Feb 2009 Location: France/or Devon. Posts: 14,003 Thanks: 3,851 Thanked 2,167 Times in 1,816 Posts	Crankshaft pulley beginning to fail ????? Will judder in all gears and revs.

17th November 2018, 16:47	#10
championdaddy This is my second home Mg Zt 190 Join Date: Apr 2012 Location: The FIRST Garden City....Letchworth. Posts: 6,778 Thanks: 1,243 Thanked 920 Times in 698 Posts	I too think it is drive train related. The car still starts great so I doubt the clip is to blame. Seems to happen under load if you labour the engine ( high gear, low speed) So I agree with SD1too........... could be fly wheel