RSricRS

iTrader: (2)

Having a bit of bother with the s2 it's hunting from 500-2k and when you give it a little throttle it runs rough??? It all started off when I was out and all of a sudden I heard a loud hissing noise just like an air leak when I got back home I discovered that the idle speed control valve was very loose infact both m5 bolts weren't even there!! So it basically wasn't on, now I've since bolted it up tight and it's running as describe I haven't got a clue what it is can some of you lads shed any light please? It's running efi.

Cheers,

Ric

johnnysash

Air leak?

RSricRS

iTrader: (2)

[QUOTE=johnnysash;6000794]Air leak?[/

Had a look at hoses and vac tubes and all appears to be fine, am puzzled? It's since that iscv come loose can you clean the iscv? And how? Really bugging me.

matthart

Idle valve can cause crazy idle but shouldnt make it run rough, if you remove the idle valve does the idle settle? (might be a bit high or low without the valve but shouldnt hunt)

Unlike an MFI, the EFI's don't really care about an air leak outside the inlet manifold, but any of the sensors going wrong can make them run really crazy.

Check the pipe to the MAP sensor for splits etc, try unplugging the MAP (I think they will run without it) or the air temp sensor on the inlet. If it behaves a bit better after unplugging either then you might have found your culprit.

RSricRS

iTrader: (2)

When you say undo the idle valve what exactly do you mean? Disconnect the iscv connector? If so I've done that and it just cuts out, I have checked all the vac pipes as well and still no luck is there any other sensors I can check and where abouts are they?


No ford fair for me!!!!

matthart

I mean't remove it completely just have a pipe there instead, see if it hunts then

RSricRS

iTrader: (2)

Can you clean the iscv?

matthart

You can rinse out the valve bits with petrol or carb cleaner, but the actual solenoid I don't know if you can look at.

Remember once the throttle is open the idle valve is useless so it wont explain your rough running

RSricRS

iTrader: (2)

Right ok, what checks can I do? There must be a list of things to check over? Air leaks but where? Spark? What else? Got the car booked in at nms for a re-map on the 3 september so want it running right before I drive there it's only 40 odd miles.

johnnysash

Could have been an air leak on the iscv so make sure you have a good gasket on it. Iscv are a known fault on later engines like the zetec and you can get away with cleaning them with carb cleaner SOMETIMES. May sound a bit silly but as you have efi you could make use of "diagnostics" by buying one of them guns on fault code readers type in "fault code reader for older makes of cars" into eBay and there is one in Wrexham for £8 at the moment...... It will not give you a conclusive fault but it should direct you to the right circuit.... Maybe!

Good luck