Hi all, I'm stuck with this puzzle of a car, it's a 1.4 mpi mk1 fabia 8v, it's been misfiring on and off for a month or two now, rough idle, looses power alot and stalls. I've changed coil pack, air filter, spark plugs, crank sensor

Now I can't find out why this is still happening, I've read online it could be map sensor, ecu, and fuel injectors?

Fuel injector wise, can I have my car running and disconnect one fuel injector at a time to see if there the problem or is that dangerous and could possibly damage the engine?

Thanks Sean.

Instead of self diagnosing it yourself have you had it plugged in to read any faults?

I did have it read, came up crank sensor to low - which I then changed, said it was misfiring which is still happening, I had it all wiped after crank sensor was changed but haven't yet got it read again, I will go get it read today hopefully

Sean.

Has the timing chain been replaced recently?

 

IIRC there were a batch of gears which had the locating dot a tooth or so out meaning when the chain is aligned (12 chain links) it ends up being out of time.

Timing chain was replaced when I bought the car back in July 2013,

I just had my car read and the faults are showing..

Cylinder 2 misfiring

cylinder 4 misfiring

Camshaft sensor

And a lambda sensor failed?

Me and my mate (Mechanic) who works for the garage I bought the car off, is gonna replace lambda sensor AGAIN on Friday see what that clears up

Have you replaced the plug leads, you don't mention them.

Plug leads? The leads leading to coil pack?

Yes.

Coil Pack ?

 

DB

Changed the fuel filter? You should also do a pressure test on the fuel pump as it might be that. Mine had similar issues and it turned out to be the pump. ~£20 off ebay and been fine since. 

Timing chain was replaced when I bought the car back in July 2013,

I just had my car read and the faults are showing..

Cylinder 2 misfiring

cylinder 4 misfiring

Camshaft sensor

And a lambda sensor failed?

Me and my mate (Mechanic) who works for the garage I bought the car off, is gonna replace lambda sensor AGAIN on Friday see what that clears up

 

Surely a failed Camshaft sensor will not be telling the coil pack to fire at the correct time, hence Cylinder 2 n 4 misfiring, therefore messing up the exhaust gas oxygen mix, hence a lambda sensor fault.

 

Id check the Camshaft sensor before buying a new Lambda sensor, especially if it has been recently replaced.

You'd get an all cylinders misfire with a failing cam position sensor, 2 and 4 could just be the plug leads breaking down in all this wet weather.

You'd get an all cylinders misfire with a failing cam position sensor, 2 and 4 could just be the plug leads breaking down in all this wet weather.

 

If he has the 1.4 MPI 8V which has the Timing chain, there are No HT leads, the Coil pack bolts straight on.

Oooops. My bad.

Forgot to mention I changed fuel filter when I done crank sensor, good job I changed it as it was the original still on! And yeah coil pack bolts straight on was abit puzzled when you mentioned leads haha, well it's a spare lambda sensor of my mates Ibiza which his gonna try, really confused why I've got these problems

Sean.

If camshaft fault still there, check the wiring as they commonly break on these. And as said check the injectors as I recently replaced 2 on an 11 plate Ibiza 1.4. You're safe to disconnect in turn to check if missfire stays the same or becomes worse. No damage will be done to the engine only codes stored etc. This should give you an idea. As I'm doubtfull a faulty lambda probe will give you a missfire on 2 cylinders. Olly

Misfire on cylinders 2 & 4 sounds like one half the coil pack is duff....................or the supply voltage to the coil pack is low,but that would trip other codes.

 

I know that the coil pack bolts straight onto the spark plugs on these cars but can't remember if it is a "wasted spark" coil pack like the 16v where it is divided into two internally & one half does 1&3 and the other half does 2&4.......

 

My mate had a 1.4MPI which I did work too, & my other mates MK4 Golf GTI had lots of misfires ...........caused by duff coil packs & the dreaded ignition wiring loom breakup/heat damage................ 

Fab, wasted spark coilpacks on 1,3,4,2 engines have 1 & 4 and 2 & 3 twinned for obvious reasons, if that's what you're getting at.

Fab, wasted spark coilpacks on 1,3,4,2 engines have 1 & 4 and 2 & 3 twinned for obvious reasons, if that's what you're getting at.

 

 Doh!....................brain fart!..............

 

But that doesn't fit nicely with the fault.......  ......bugger.....back to square one with you faults mate (op)

I've got the skoda fabia 1.4mpi 16v and I'm getting the same problem however I'm just getting cylinder 3 misfire, I've changed the coil pack, plugs, air filter, oil filter cleaned the throttle body and I'm still getting the misfire, however when I fiddled with the leads going into the coil pack it stopped misfiring, where do I buy these leads from and are they hard to replace

Thanks for all the replys guys, well my car has been okay at this moment in time, no revs dropping, no cut outs, still a rough idle, all we did was clear the faults showing on code reader but yet still gonna have a look Friday replace lambda sensor nd read it again, I would like to replace fuel injectors where could I buy new ones from any ideas??

Sean.

I've got the skoda fabia 1.4mpi 16v and I'm getting the same problem however I'm just getting cylinder 3 misfire, I've changed the coil pack, plugs, air filter, oil filter cleaned the throttle body and I'm still getting the misfire, however when I fiddled with the leads going into the coil pack it stopped misfiring, where do I buy these leads from and are they hard to replace

 

Easy to do, you can get them from any motor factors, about £25 for the set. simply replace them one at a time then you won't get mixed up with which one goes where.

Thanks for all the replys guys, well my car has been okay at this moment in time, no revs dropping, no cut outs, still a rough idle, all we did was clear the faults showing on code reader but yet still gonna have a look Friday replace lambda sensor nd read it again, I would like to replace fuel injectors where could I buy new ones from any ideas??

Sean.

 

Very unlikely that you need new injectors, however you can get them cleaned ultrasonically which is worth doing.

Very unlikely that you need new injectors, however you can get them cleaned ultrasonically which is worth doing.

Where can I get them cleaned? Any ideas? And rough price?

Sean.

Where can I get them cleaned? Any ideas? And rough price?

Sean.

 

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