Newbie here :P

My Focus has had a rough idle for awhile now and I can't seem to solve it.

So far I have replaced the spark plugs which made things smoother when driving and a hose behind the inlet manifold part no 1337254. we have checked for air leaks, took off the idle control valve which looks like new, cleaned the MAF. When starting the car it turns over for 5 -6 sec before starting but always starts and never stalls but then smells strong of petrol for about a minute or so then will idle around 1100rpm for awhile the drops to two lines below the 1k line. I had a family member plug it in on a snap-on diagnostic which said it was bank 1 Lambda sensor (can't remember the fault code) but then at the bottom of the screen it also says other problems could cause this fault code. Could it really be the lambda? ford quoted £197 for this sensor can I find it for less anywhere else?

Thanks in advance.

Also forgot to mention we have check all wires and connections.

Edited February 27, 201214 yr by L600MAT

May I suggest eBay.

Far cheaper.

Btw I believe there are 2 sensors on your car.

I'd assume bank 1 refers to the front one?

Someone here I'm sure will be able to advise on that.

bank one sensor one is the front one before cat

I think this will be the one then.

http://www.ebay.co.uk/itm/Lambda-Sensor-Front-Oxygen-FORD-FOCUS-Mk1-1-6-98-/400273992099?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item5d323069a3

I would assume the quote you had was for fitting too?

The front sensor is easy to get to on the downpipe, unplug the cable and unscrew the sensor from it's hole.

Do not drop the new one or touch the end of it.

Use some anti-sieze compound on the thread and install.

Bear in mind that the fault code will need to be erased for full function to return as the system would have dropped to LOS (limited operaton strategy or commonly known as limp mode) and needs to be reset.

I'd also advise an emmisions check to confirm functionality.