Ford Focus chugging and backfires.

punisher5112

Hi all I have a 2007 focus 1.6 petrol.

It had a very rough idle and changed out the throttle body and it fixed this but another issue that was there is just as bad.

It chugs and backfires and while putting power down it cuts then comes back.

It could well be the coil pack but ive had many of the 1st gen and when they went they behaived different.

Just wondering if its maybe a sensor issue either.

No codes showing or engine warning.

Four Phucs Ache

I've only just yesterday fixed a very similar issue in my 04. 1.4

Idle was crap and when I put foot down it would do nothing or struggle then surge.

Intake Manifold breather pipe had degraded and was sucking itself closed when revs increased.

New pipe was 15 quid and I cleaned the pcv valve and it's back to normal.

Granted , this may not be your issue but very similar symptoms​.

Stoolbend

Could be water around the spark plugs.

jimbis

With the engine idling, remove a plug lead from the coil end just enough to see the spark arching, then pop it back on. If your coil is doomed then one of these won't be spark/arching and you need a new coil.
Might not be the problem but it's a way of ellimnating a faulty coil which is very common.

punisher5112

Stoolbend wrote: »

Could be water around the spark plugs.

I put new plugs in at last service I done on it.

Ive had loads where coil pack failed just the symptoms are a tad different but could well be an issue.

No water was in the plugs.

martyc5674

punisher5112 wrote: »

I put new plugs in at last service I done on it.

Ive had loads where coil pack failed just the symptoms are a tad different but could well be an issue.

No water was in the plugs.

Often with coil packs breaking down if you look under the bonnet in the pitch dark (keep your hands etc away from moving parts!!)... have someone rev the engine and you may be lucky and see some arcing around one or more of the packs confirming your problem.
Marty.

Waterson

The focus has a good self diagnostic strategy...but it may take a few days after the battery has been disconnected/codes cleared for all the tests to be run, I'm surprised you have no fault codes given the symptons. If you have access to a generic fault code reader you can get individual misfire data under the mode 6 section ($6 )which may point you toward a specific cylinder to diagnose your problem. I can only speculate but it sounds like a valve timing issue. When was your timing belt last changed?