Sometimes (every 2 or 3 months) my Fabia 1.9TDi refuses to start, often after it's been left standing for a day or two.

Battery turns over the engine fine, it just doesn't fire up.

So I get out my can of Easy-Start, unclip the air intake hose, squirt some in and it starts - not ideal but it gets it going. Occasionally the engine will restrict the power a bit later that journey for 30 seconds or so, usually on dual carriageway or motorway. (This sometimes happens on other days when it's started without Easy-Start but reluctantly).

The dealer can't diagnose it, because it never misbehaves on the dealer's premises.

I don't know much about VAG-COM, but if I had a copy & plugged it in when the engine's not started, might it log some info which would help diagnose the problem? (Bear in mind I wouldn't know what I was looking for.)

It wouldn't automate the process of logging the startup for you or anything. It would allow you to read any stored codes or to read Measured Block Values (MBV's).

Are the glow plugs ok? Has it been regurlary serviced?

When she does start, did you check the exhausts, black smoke, liquids.

What if you undo the hoses, but do not squirt anything in it; just leave it to air. does she start then?

When you are driving, you say you lose power. how does this manifest itself? do you get warning lights on the dash?

I think, with what Stu is saying, is that the garage should be able to pick up intermittent faults, as they get logged in the ECU.

Thanks VRStu and G-Slave.

It's always been regularly serviced at a Skoda dealer - but they've not been able to find any logged faults. They also changed the glowplugs (they didn't find a specific fault but they were looking pretty worn) but it didn't cure it.

When it's doing this I don't think it starts with air intake unclipped unless there's some Easy Start in there. Most of the time (when it's not misbehaving) it starts quickly at the 1st turn of the key.

Not noticed it being particularly smoky or any extra liquids (but haven't looked for that specifically on these occasions). Not noticed any fluid leaks though.

Loss of power usually happens on NSL roads like m-way or dual carriageway. No warning lights or beeps, just gradual loss of speed. It feels a bit like it does when you push the throttle and brake at the same time for example, albeit more severe.

It tends to lose speed to 50mph or so, but for some reason I can then change down and the power comes back. I've also noticed this power loss on a couple of days when I've not used Easy Start, but the engine was a bit spluttery and didn't start immediately (as it normally does).

Thanks for your help,

David

I would check the condition of the air filter. You might find the fuel filter needs changing too if it's not been done recently.

Other than that you might be looking for split pipes.

So from what you are saying the engine management system is unaware of this problem.

I used to have this on my '81 van which, it was down to the carbs being incorrectly set; the mix was incorrect. i know it's a long way to compare a these 2 engines, but I'd be tempted to say either the air or the fuel is not 'getting in there on time'.

My dad had this problem on his 2000 Golf Mk4 TDI, the air mass sensor was not doing what it was supposed to do.

have you had any modifications?

When was it last serviced?

What is the history of the car?

Status Air filter?

Fuel pressure?

All I can think of ATM

Thanks for your help...

Since finding the fault (back in January) it's had a couple of investigative trips to the dealer plus subsequently 200K and 210K services. It only misbehaves rarely, and seems to get most upset when I don't use the car for a day or two. Last time was last Sunday, but the time before was 4th June.

I seem to remember air filter are changed every 40,000 miles so I believe it would have been done at 200K (?). I asked the dealer to look at fuel filter on one of those visits, I believe, as the breakdown man suggested it.

Not sure how I would check fuel pressure? (Bear in mind I don't have VAG-COM - my original post was because I was wondering if it would help diagnose).

If it's split pipes, how would I know?

No mods - all original - and car's been mine since new and always serviced regularly at Skoda dealer.

I don't think it would have an effect on the starting but perhaps a cause of your loss of power, given the mileage, would be sticking VNT vanes on the turbo.

Thanks for the turbo thought - but I've only noticed the loss of power on days when the starting has been suspect, so I think there's a link somewhere to the starting problem.

It's on its 2nd turbo too - the 1st one died while it was (just) under warranty - so the turbo has only done around 100K miles.