Engine light and misfire in 2005 ford focus 1.4 diagnostic computer Reading cylinder 3 misfire.Changed spark plugs ht leads and coil pack but car is still misfiring. Diagnostic computer reading cylinder 3 misfire changed injector number 3 but engine light remains on and still misfiring.can anybody help??

Brian, November 2011

If it is the same problem my daughter had, it didn't matter how many times we dried out the moisture. Every time the engine was started again, more water was forced out through the leaking core plug.

In the end it was repaired using a liquid metal filler. That worked until the car was sold a few months later. I don't know about how long after that.

Still, try your compression test if you think it is low on compression on that cylinder. But if it isn't, remember what I told you.

ChicksFan, November 2011

I'm thinkin of comprfssion next don't know what else it could be at this stage. There was moisture bt dried it out wit airline and still misfiring.. Thanks

Brian, November 2011

I'd check for moisture down the plug hole. My daughter had this with an Escort. There was a leaking core plug down the plug hole in the head casting. When it got to normal running temperature it sprayed steam onto the plug and caused a misfire.

I don't know whether the cylinder head design has changed that much since then.

ChicksFan, November 2011

you could check compressions,worth a look

cdc, November 2011