Bought a scrappy 2007 Fiesta 1.6 to mess about with and learn some bits. 
 

Had everything running beautifully but decided to do some service jobs as I had no history of the car, oil, filters, fluids and spark plugs. 
 

Doing the spark plugs I found the wells, especially 3 & 4 had pools of oil in them, quick bit of research lead me to replacing the rocker cover gasket, not too bad of a job, just a lot of scraping! Pulled the spark plugs and cleaned them up, as well as the wells while I had the rocker cover off. 
 

Starting it back up again, it stalled out right away, so I gave it some throttle starting it, then gently lowered the revs to idle but it seems to be very rough, engine block looks like it’s trying to escape and the exhaust is emitting some coloured smoke and sounding very tractory. 
 

I replaced the airbox with a little K&N filter, as that was rubbish, naturally that make no difference.

 

Pulled the sparks and leads, checked gaps, re-seated them but no joy, still got a rough idle which eventually stalls out to give check engine code P0300.

 

Any ideas on what I should start looking at next? 

Any advice/help would be appreciated.

Short video below of the idle sounds.

Thanks in advance.

 

 

If it was working alright before and you are 100% sure the Spark Plug leads are on the correct cylinders and you have not dislodged an electrical connector or any of the pipes then put the old Spark Plugs back in and see if it runs ok again.

The chuffing from the exhaust does sound like a misfire/low compression problem but from the engine side the noise sounds like a Valve Gear problem or wear. Very difficult to tell from a recording.

The other thing to do if you are serious about learning about Fords is to get set up with FORScan. There should be PID's that will narrow down which Cylinder is causing the problem and Misfire Counters in Mode 6. If you don't want to do programming then the phone version with a quality wireless adaptor is more convenient for Live Data Monitoring.

Sounds like not all cylinders are firing.

did you put the leads back on in the correct order as thats only running on 3 cylinders you can hear the misfire, also were the new spark plugs gapped i know a lot of them come pregapped but it doesn't hurt to check ?

Watched several videos, it was the HT leads, feeling like a proper dunce now as that was my first port of call, pulled them out and started again, obviously dead wrong the second time! 
 

Thanks for the help! 

2 hours ago, MassiveSpac said:

Watched several videos, it was the HT leads, feeling like a proper dunce now as that was my first port of call, pulled them out and started again, obviously dead wrong the second time! 
 

Thanks for the help! 

don't worry about it mate, we all make mistakes i work on cars all the time, and i still make stupid mistakes