My girlfriend's Y-plate Fabia 1.4i 16v is driving me/us nuts. Since buying it a month or two ago, it has consistently been a poor starter. When cold, the engine fires but runs on two or three cylinders for a few seconds and then eventually (but somewhat reluctantly) responds to throttle. When hot, it fires straight up OK. I replaced the coil-pack (genuine Bosch) and that improved things to a degree, and today I replaced the plugs. After that it seemed to drive far better, pulling stronger up local hills etc. Then, when I got home, I left it for about 20–30 minutes, no more, and guess what? It struggled to start, ran rough and took a few seconds to clear itself.

Any ideas? At the mo, it's our only car as mine is away being repainted, so the Fabia's got earn its keep!

Cheers for any help...

Does it burn any oil?

It doesn't burn any (oil level remains constant) but does have more blow-by (from breather) than I'm used to. I guess you're suggesting oil-fouled plugs, loss of compression, worn rings etc?

Worn rings is a common issue on these engines. Might be wise keeping an eye on it overtime. Blow by is common as well.

Err, my suggestions would be maybe the battery not holding charge (unlikely though from what you explained), or the temperature sensor, as that can cause odd running and bad starting (thanks reflex for that tip if you read this!).

Also, yours is cold after 20-30 minutes? I can leave mine an hour or more and it's still warm on the temp. gauge.

No, not cold – just that once I had left it for that period, the symptoms returned. Hmmm, maybe temp sensor?

Ah, ok.

Yeah, from what I have been told, the temp sensor tells the engine how the fuel:air mixture should be, and if it's giving bad readings it could be over/underfueling. That might be the cause of the rough starting, but wheather or not it would only mean 2-3 cylinders or not I don't know.

I'd first try a VAG-COM scan, then cleaning/aligning the throttle body, and check the temp sender.

Temp sensor is pretty cheap, and it sounds similarish to mine when the temp sensor was dodgy. I didn't have any abnormality on the temp gauge. Part is certainly cheaper than paying for a diagnostic check; if it were me I'd do it and see what happened.

The part is on the front nearside of the engine block from memory, unclip the ring around it after draining the coolant and it just slides out.

Also use some good Super Petrol 98 RON or more (Shell V-Power or Tesco 99+), as recommended for this engine, it will also clean the injectors a bit.

Cheers. Now losing coolant... I'm worried may turn out to be head gasket problems...

If the coolant is going into the oil then it can be the head gasket leaking, can you see where the coolant is leaking? It is not uncommon for head gaskets to fail in 1.4 engines.

The coolant loss could be from the fan switch on the passenger side of the radiator. I've seen a few of these with starting problems where the tempersture sensor will suddenly report -18 deg C and then a second later will report the correct temperature.

The 1.4 16V engine is not known for head gasket failure (unlike the 8V unit which does have a reputation for blowing HG's).

Coolant leak could well be rad temp switch (just above bottom hose connection on low near-side of rad). Feel down there for dampness and wet patches on the splash shield.

Poor starting could be a number of things - a poke-and-hope approach could take time and entail replacing a number of good components until a cure is found. Best approach would be to use VCDS (or some other scanning software) to look at live data.

i had problems with my 1.4 16v where it was jerking when accelerating and it was the MAP sensor. this was replaced and it now runs really well