A single knock when pulling away

tres · 13 Apr 2015 at 15:28

Hello motors,

08 Ford Focus.
When I pull away 'hard', or change gears with a bit of revs, I get a single knock. Not always, but started yesterday and happened 10 or so times these last couple of days. And otherwise a perfect car. Any ideas what this could be?

teenwolf · 13 Apr 2015 at 15:31

engine mount maybe ?

leigh_boy · 13 Apr 2015 at 15:39

engine or gear box mount 100%

tres · 13 Apr 2015 at 19:27

Cheers chaps.

How much is this going to cost me? Is it an immediate fix required?

mattyg · 13 Apr 2015 at 19:44

Get it sorted asap. Not sure about on the Focus but on my old CRX when the front mount goes (can be checked by backing off the throttle and a second or so later you could feel the engine drop) It can knacker the diff pretty quick.

Engine mounts are cheap

teenwolf · 13 Apr 2015 at 20:32

Cheap job

Iamzod · 13 Apr 2015 at 21:45

Cost me about £18 to DIY it on my MK3 Mondeo.

ShiWarrior · 13 Apr 2015 at 22:10

Just a thought

is it like a "clunk" noise? if so that's normal, I know all MK2.5 Foci do it when you get to like 5 MPH

tres · 14 Apr 2015 at 13:02

ShiWarrior said:
Just a thought

is it like a "clunk" noise? if so that's normal, I know all MK2.5 Foci do it when you get to like 5 MPH

It is, I've heard it's the ABS or something? Never had this noise before though, it's when I pull away, even when travelling above 5mph.
Thanks to all. Will find a garage.

Conscript · 14 Apr 2015 at 13:06

Any noise when you stop?
Had similar on my MX5 and it was a single knock when touching the brake pedal then another when pulling away. Caused by the brake pads shifting slightly in the calipers and nothing to worry about.

But of course it only happened once for each time the wheel changed rotation, so I guess this isn't what you're getting as it happens on gear changes, but thought it might be worth considering.

pull2808 · 14 Apr 2015 at 13:13

It sounds very much like the knock i also hear a bit. 08 focus and like you say it's a knock when you have a jerky gear change. Not taken it to the garage yet but interested to hear people's thoughts.

tres · 15 Apr 2015 at 14:07

Just took it to a garage - apparently the mounts are fine, they think it was an exhaust bracket that had broken off and was causing the knock when accelerating. It was attached to the front pipe. They suggested it should be fixed back on (they were unsure whether it was an MOT fail to have an exhaust bracket missing) as they just took it out, but said the car was fine to drive in the meantime - just a bit of extra stress on the exhaust.

It looks like I'll have to find someone who can weld it back on. Apparently the bracket is part of the exhaust system and the rest is in good condition, so I don't want to spend lots of money on a full new exhaust.

Can you not buy a replacement front pipe?? Do you have to get the full exhaust kit?
I'm trying to find a Haynes online to make sure I know what's going on, and then to try and find a mechanic who'll do a quick weld job...

Any big issues I'm missing, being a car noob still?
Cheers motors.