I have a mk3 fiesta si 1.6 and its nakard so i was wonderin if anybody new whats up with it?

Basically it starts up fine but then cuts out straight away, if i hold my foot on the accelerator it keeps reving up but then the revs drop then revs up again then drops again etc, its as though its only gettin bursts of fuel through. Any help would be much appreciated

 

I was gonna say fuel pump....

 

i thought that but it starts fine, could be the throttle bodies?

 

blocked fuel filter?what happens if u leave it idling?

 

ISCV?

 

is it easy to check?

 

what is the iscv?

 

Idle speed control valve.

 

will it have to be a mechanic job or can the average joe figure out if its that?

 

if it helps when it first went funny i was driving it and all of a sudden it started driving like a kangeroo but it run fine when idle but when i checked the spark plug leads it went worse.

 

You can try cleaning it and see if it makes a difference. I don't know it's location on your car but it'll be around the throttle body somewhere.

 

need to find throttle body now lol

 

As it's still erratic when you hold it on the throttle I would get it warm and check the CO, exhaust gasses, visit a friendly mot centre and ask them to pop it on the machine.
I would hazzard a guess at your lambda sensor.
tabetha

 

what is the lambda senses?

when i start it, it runs for about 2-3 seconds then dies off off unless i put foot on accelerator then it just rev's to about 1500 revs then drops then revs back to that magic number then drops again etc. also does the mk3 fiesta haynes guide cover the 1.6 zetec or is it just the cvh?

 

If you dont know where your throttle body is, or what a lambda sensor is, then take it to someone who does

 

right the iscv is under the black plastic manifold at the front of the car as you look at it, it will have two 8mm blots holding on to the engine with a electronic plu that pulls off.

Whilst you're there check the breath pipes underneath this (about 8" underneath) if these are split it will give you the same problems.

 

Disconnect the maf sensor



pic is off a later zetec but in essence the same.

Once disconnected start the car and see if it changes.

 

you fixed it! thanks wirralphil, that was the problem. you are a legend in my book now ha ha!