Hi..

Can anyone advise here please?

 

Our Fabia that I bought to teach my son to drive in has developed a problem in that its started running very rough. 

Today on the way home, the engine light came on and it felt like it was on 3 cylinders. 

Got home and read a code P0301. No.1 cylinder misfiring.

 

I pulled all the NGK plugs which looked ok, and cleaned and gapped them to 0.025. Tried each one outside the cylinder in turn and they sparked well. In case a coil pack was failing, I bought a new one and tried it in cylinder 1 and the engine (which had cooled by this time) , felt fine on all four again.  

Took it for a run, and a mile up the road, the light came on again and the hotter it got the worse it ran. 

Now with the engine hot, I seems like its struggling on two cylinders so I'm letting it cool again to see if it runs better. 

 

I don't think this is an ignition problem, and if it runs better when it cools, then maybe the increased 'cold start' fuel mixture helps it, ..but as it heats up and the mixture weakens, maybe this makes it worse,  maybe pointing to a fuel fault, but then I could be talking b*ll*cks! 

 

Anyone seen this before?  

Read the fault codes again, as a first step.

Do you own a compression tester?

 

 

Hi..

I'll read the codes again tomorrow after its cold start and see how it behaves.

Don't have a compression tester, that sounds ominous! Need to get one then.. 

 

Its a well cared for car, whoever had it before me fitted all new brakes, cam belt, droplinks et. just before I acquired it and kept it very tidy inside. Got a full service history too so I doubt if its a neglect problem. 

Sorry, wasn't trying to alarm you with reference to compression, it's just a quick and easy thing to eliminate if you have a tester.

If you get a fault code for the same cylinder, consider moving that fuel injector to a different cylinder to see if the fault moves with it.

Yes, that was on my mind to try that. I'm going to leave it to cool right down to see if my thoughts are correct, but injectors are next. 

..btw, there is an awful smell around it when it was running rough, like melting plastic. I jumped out quick but no sign of anything burning. 

The burning smell may be to do with the manicat overheating due to unburnt fuel from the misfiring?

Edited 15 October, 20205 yr by Wino
sp

Thanks for the advice, more info later.. 

8 minutes ago, Wino said:

The burning smell may be to do with the manicat overheating due to unburnt fuel form the misfiring?

You mean the catalytic converter?

Never thought of that, so maybe the ignition is at fault after all if fuels getting into the cylinders. The plugs were all sparking well though and I tried the new coil pack in each one in turn. 

Its dark now, so i'll try again tomorrow. Thanks for the advice so far, I'm sure I'll get there in the end. 

7 minutes ago, L98 said:

You mean the catalytic converter?

There are two. What's your engine code, BKY? 

16 minutes ago, Wino said:

There are two. What's your engine code, BKY? 

 

2006 it will be a BBY for an auto.

If so there's a cat forming part of the exhaust manifold, then another downstream of the flexi joint. I was referring to the first of those, which is close to things like the radiator fan/shroud and engine cover, lots of nearby plastic. See if there's any sign of melting or scorching to those areas.

It says BKY on the belt guard next to No.1 cylinder. 

I'll be under it tomorrow when its light.

Thanks.. 👍

 

Edited 15 October, 20205 yr by L98

35 minutes ago, Wino said:

There are two. What's your engine code, BKY? 

 

2 minutes ago, L98 said:

It says BKY on the belt guard next to No.1 cylinder. 

I'll be under it tomorrow when its light.

Thanks.. 👍

 

My apologies Wino

On BKY there's a precat slightly lower down, below the (separate) exhaust manifold, so further from engine cover but possibly nearer some bits of radiator fan, engine undercover.

👍

Well, no hot cat (..our wee Tilly or the car's!) burning problems. 

 

I decided to go for ground zero and fit 4x new plugs and 4x new coilpacks. This time I bought BBT packs as ECP have a big discount on offer, saving me 55gbp. Previously, I bought a HAAS coilpack, but its thicker than the originals and looks very ungainly, whereas the BBT units look more like the original coilpacks. To anyone reading this, I would just spend the extra fiver and get the BBT units..

The result is the car now runs lovely and smooth.. The mpg figure on the computer are showing 75mpg (and 62mpg average) which is a lot better than it was before if the numbers are real. 

 

Since I bought the car, it would hesitate a little in D when cold so I would run it in 3 until it heated up. Now, that has gone too. Smooth all the time.

Filled up with BP fuel and hopefully an end to problems (for now anyway). 

 

Just want to thank Wino and Tech1e for the advice. It was much appreciated. Hope this thread will help someone else with similar problems.. 

 

Happy now!