Car problem

Menthis · 8 Nov 2012 at 19:27

Had this problem a while now but dealt with it, but is really starting to annoy me now.

A little hard to explain but car seems to rev up when well it shouldn't, When i first come to a stop it will rev to say 2.5k then after a while it will drop back down. and also on gear changes it revs while out of gear! It's also a lot worse when cold or wet! but is still bad when hot...

Its a ford focus 1.8 zetec 2001

Any help?

Thank you

Menthis · 8 Nov 2012 at 20:35

Gaygle said:
Maf sensor? Idle control valve?

I have no idea what either of these are really?
what would be my best bets. Garage?

Menthis · 9 Nov 2012 at 08:40

I shall have a look around then.

Menthis · 9 Nov 2012 at 10:58

Is the focus zetec a cable operated throttle?
A few people said it could just be a sticky cable.

Menthis · 14 Nov 2012 at 19:44

Have had the idle control valve cleaned and cleaned the MAF sensor myself seems pretty clean in the first place.

Both have not helped
Not sure what else it can be other than the sticky throttle cable. Is it easy to replace myself?

Menthis · 15 Nov 2012 at 09:51

MatteH Oxford said:
I wonder if you have a vacuum leak?

Do you have access to an OBD tool? It would be interesting to see what you short term fuel trim is @ idle, if it's high +10%) then drops to 'normal' as you hold the car at approx 2500-3000 rpm then you have unmetred air getting past the maf.

I'd also expect to see a long term fuel trim of around +7% if it's the case.

*edit* car has to be warm & the o2 sensor operating in closed loop when testing!

I don't know what an OBD tool is, not really too technicall when it comes to cars.
What do you mean by fuel trim?

Menthis · 15 Nov 2012 at 09:52

scratch said:
I dont know if the Focus has one but I've heard of this kind of problem on VAG cars being caused by a dodgy clutch pedal position sensor.

This is interesting. I have a weird clutch hard to explain.

Menthis · 15 Nov 2012 at 13:20

The only thing i experience is when i slow down to come to a stop it will sit at the revs it was at from being in gear, and go up slowly till about 3000 revs, then when i finally come to a full stop it will drop down.
Plus i can never have clean gear changes because it revs up during the change of gear. Its weird because some times its fine.

It also seems to idle fine, doesn't jump around sits at about 900revs i would say

Looks like ill have to take it to the garage to get it fault read i guess, i had a mate put in a one of these fault code readers but it gave no errors..