my mk 2 fabia 1.4 tdi has always been a very good starter until the other day when it was very reluctant to start as such i felt that the heater plugs were faulty but then two days later it started too cough and splutter and lost power intermittently which now makes me feel that it is a fuel problem and most likely a dodgy fuel filter and requires changing and was just wondering if anybody else had got any ideas on whats going wrong 

Please note - I am not a mechanic or expert in anything.

 

There are people here that will be able to help you (not me on this very probably) but more information will possibly be required.

 

What makes you feel the heater plugs are faulty or that you might have a dodgy fuel filter?

 

More information about your car, history, servicing, maintenance, repairs and driving conditions and the failure to start and later cough and splutter and internment power loss will help.

 

Do you have any warning lights or messages, access to a scan tool or error code reader, know the condition of your battery and connections/cables (you particularly need the battery in good condition if you have starting and/or electrical issues).

 

Guesses could be made for lots of things but you want from yourself and others proper diagnosis.

 

Edited 8 November, 20223 yr by nta16
ETA: Please note - I am not a mechanic or expert in anything.

Please note - by co-incidence I am not a mechanic either. 

 Modern diesel such a yours do not really need heater plugs to assist in starting, and would not result in loss of power intermittently. Unless you have any history of fuel filter changes, given the relative low cost I would suggest changing this as a starting point, but you need to have the car scanned with a VAG group compatible scan tool. If the car turns over at the normal speed when starting I would not expect battery issues - my 1.4TDI has always started, even with an extremely tired battery - no problem with having it tested but do not be drawn into automatically buying one as voltage has to be extremely low to give issues with running (my 1.9TDI threw its drive belt off after the tensioner failed and carried on driving for another 15 miles until issues with running showed, at which point turning the key to the starter position after switching off just resulted in a click from the starter).

 To clarify the issue:-

Has the reluctance to start been a one off, or is it now a recuring daily problem.

Is the cough/splutter just after starting, or even when warmed up and running, and is it a recuring issue.

Is the intermittent power loss a one off or again a recuring issue.

hi just a bit of an update the battery is good and the engine turns over good .i have checked the glow plugs and they are all working ok .i have changed the diesel filter primmed it up ect then turned the key several times just  to make sure was flowing ok then tried to start the engine and he presto all started great run great i then revved the car several times and run on the drive for about 5 mins all seemed great so i had a coffee and cleared up .then tried it a bit later and he presto it was hard to start again and with very little power .doesn't make a lot of sense to me especially when no engine warning lights are on .im trying to find a mobile mechanic to do a diagnostic check on it but they don't seem to be reliable to even return a phone call so a bit stuck at the moment any ideas would be gratefully  received

How did you get on with the mechanic, I've got similar issue at the moment (struggles to start / long crank).  Tried all the usual things you've tried and now starting to think it could be either.  Crank position sensor or tandem pump leak (fuel and brake vacuum pump).  Hope you got it sorted.

the car is still in the garage they plugged it into the computer and it came up camshaft sensor fault they replaced the cam shaft sensor  and the car run ok for about 45 mins then stopped and gues  what plugged it back in and hey presto cam shaft sensor fault so it seems to be heat related and might be a wiring fault but the cables appear to have continuity ok  my thoughts are more towards a bad connection  or a bad ecu  but cant say for sure so im rely stuck at the moment so any suggestions would greatly received   

On 09/11/2022 at 19:53, KeithCheetham said:

voltage has to be extremely low to give issues with running (my 1.9TDI threw its drive belt off after the tensioner failed and carried on driving for another 15 miles until issues with running showed, at which point turning the key to the starter position after switching off just resulted in a click from the starter).

 

I drove 200 miles after my alternator stopped charging on a MK1 Octavia 1.9TDi including a 2 hour ferry journey and having to restart the engine on disembarkation and then driving 90 miles at night with the headlights on.

 

I could not believe how far I got and was gobsmacked to find that it actually restarted the next morning, it was a couple of weeks before I could get a replacement brush pack but I had no concerns because I knew by then that it had a great autonomy on the battery and so I would only trickle charge it every other night.

 

When I reflected I realised the engine had a mechanical injection system and fuel pump, while I was driving the only thing using current was the ECU, the instrument binnacle, a couple of engine sensors and the fly by wire throttle, later cars with electronic injectors, lift and scavenge pumps and all the other malarky would not have the same autonomy but 15 miles is not much at all, petrol engines easily do more than that.

Sounds similar to an issue I had recently with my 1.6tdi. Turned out to be faulty wiring between the ECU and MAF.