Hi all,

 

Hoping someone else has came across this issue and is able to advise please.

 

My 2010 mk2 Octy 1.9 tdi has recently developed a starting fault where is cranks (very fast) but doesn't start. At first I thought it might be the fuel pump in the tank but I can hear it priming when the ignition is on. It ran absolutely fine before this starting issue.

 

Plugged in the fault code reader and it came up with 5 codes: 

 

1 - powertrain data bus missing message from instrument cluster (cleared codes, tried starting again and this did not reappear)

 

2 - Glow plug for cylinder 1 open circuit

 

3 - Glow plug for cylinder 2 open circuit

 

4 - Glow plug for cylinder 3 open circuit

 

5 - Glow plug for cylinder 4 open circuit

 

(All Glow plug open circuit faults reappeared after clearing the codes and tring to start the car again).

 

At first I thought it was a fuel issue, but after seeing the codes for all 4 glow plugs, I'm thinking it may be an issue with them / the glow plug unit? Also thought about the camshaft / crank position sensor, but there is no code showing for this.

 

Would really appreciate any help / advice please.

 

Thanks , Kev

 

 

Glow plugs are cheap so worth checking/replacing before the cold weather.

On the Mk1 1.9 TDi engines it was a common problem of failure of the relay which supplies power to the glow plugs. Difficult to check at this time of year as the glow plugs only come on at low temperatures.

In warmer weather the glow plugs are not needed.

Your details show a Mk1 TDi so if this the case I suggest you copy your post to the Mk1 Forum for their additional knowledge.

If it is a Mk2 then please add the engine code i.e. ASV, BMM etc

 

Mike

Thanks for the reply Mike.

 

Will probably change the glow plugs as like you say they are cheap, but just seems strange that all 4 would come up as an open circuit at the same time and wasn't sure if that would cause it not to start when the temperature is quite warm at the moment. 

 

Sorry I have updated my details. It is a 2010 mk2 octavia 1.9 BXE engine code.

 

Thanks 

 

Don't waste time and money replacing the glow plugs, the 1.9 starts fine without them, even in a Scottish winter.

 

Do a quick check by pulling the leads off and checking the resistance between each plug and ground, a good plug should be < 1Ω.

 

To check for fuel starvation, try using some Ez Start aerosol, if it offers and sounds okay then most likely an electrical/sensor issue I would think.

 

When you write "it cranks (very fast)", do you mean faster than usual implying less mechanical resistance than usual or just lively as with a healthy battery?

Edited 28 June, 20205 yr by MicMac

Cranking very fast, noticeably faster than usual usually mean the cam belt has broken or the valve timing has slipped and the valves have contacted the pistons.

 

+ 1 to the easistart test, its a vital piece of diagnostic equipment.

 

Change the glowplugs when you can, one winter you might need them but they wont be causing you any problems at present.

Edited 28 June, 20205 yr by J.R.

On my 1.9 when I lost 3 glow plugs in winter, it would only start after longer cranking accompanied by white smoke and a lot of engine shake until all cylinders were firing. I would recommend replacing  the glow plugs before winter, assuming the rest of the engine is ok.

Thanks for the replies everyone. I re scanned it again and the 'powertrain data bus missing message from instrument cluster' code came back up. Think this might have more to do with it not starting than the glow plugs. Anyone came across this fault before?

Since you didn't specify any specific DTCs I did some digging on your behalf and would suggest the instrument cluster has a bad solder joint/plug connection that's tripped the immobiliser or at least not giving the go signal to start.

 

As a quickie try giving the dash area above the instrument cluster a good few thumps or have a poke around relays/connector plugs.

 

Also try disconnecting the battery for a while, it's unknown how long it may need.  From 10 minutes to overnight!  Seems a complete reboot of the electronics can sometimes fix things that get corrupted.

Edited 30 June, 20205 yr by MicMac

Hello,

I am having a problem with skoda octavia mk2 2009,118k miles on clock,car will start fine first turn when cold and will not start warm unless i labour the starter keeping the key turned till it fires up,i have the coolant temp sensor disconnected and car will start hot or cold,this problem is going on 4 weeks now 😞 i changed the fuel pump first in a silly panic,then after some research i changed coolant temp sensor,still no luck 😞 there is no fault codes coming up,i brought to garage and they changed the crankshaft sensor,still same problem!!! checked the battery and it is fine,can someone explain the starter issue as i seen some have solved this problem with a starter but im confused at this stage,someone asked if the starter how will it start cold?what part of the starter becomes worn or faulty that it causes the problem to not start when engine is warm or hot?I am really getting stuck at this stage and spent silly money trying to fix this problem and still back to square one.Can anyone please help?

For some unfathomable reason the ECU has to detect a cranking speed over a certain threshold when the engine is hot but not cold when as you know it will start in 1/4 revolution barely cranking.

 

Battery & starter condition also the crank sensor can all conspire against the ECU believing the engine is rotating fast enough, attention to one or all of them usually cures the problem but there is a software upgrade I believe to remove the stupid feature otherwise you will need to fit a N/C momentary pushbutton in the CTS line to fool the engine that its cold, although it will probably need a shunt resistor across the contacts to avoid fault codes.

 

It really is a stupid feature and I cannot see the logic behind it.

 

Editted, if you muck around with shunt resistor values till you find one that does the trick you could make a slick and undetectable system using a relay triggered by the solenoid feed when cranking.

Edited 1 July, 20205 yr by J.R.

Thank you very much for reply, so if I get starter reconditioned it should sort problem? I topped up with oil few days ago and tonight yellow oil lamp flashing when I turn ignition before starting, I checked oil level and it is fine but could this be something connected to starting problem? Also I have had to drive it last few wks with coolant temp sensor disconnected as need to work, could that cause damage? Maybe I'm panicking now, I changed crankshaft sensor and coolant temp sensor 

Hi all, Had exactly same problem today! ( 1999 Octavia Mk1) Car usually starts very quickly and did so today, glowplug light went out and engine immediately fired. Drove very short distance, stopped car and it would not start again- glowplug light not coming on, engine spins as fast as usual but no firing! . I'm guessing a relay ,as previously suggested but will get VCDS plugged in tomorrow. Thanks for all hints/clues/suggestions. D

Let me know how it goes

 

Plenty of warm/hot start threads just picked this one to add my experience for those reading for solutions.

 

reading the various threads pointed to the battery being a good candidate due to its age.

 

50k 2008 1.9 original Varta battery  the annual checks have show cranking amps dropping off for the last 4 years.

 

Not used much since March(lockdown)  dropped the ctek on for some longer periods of non use.

 

getting the warm start issue when started using it again,  battery check showed it had dropped to 350A(June last year 390A) voltage OK 12.3v

It sounded like it was cranking OK but nothing,  which checks with the no fuel cut off.

 

Swapped  in a  Varta e44 and that seems to have fixed the issue for the few runs done, hopefully none of the more expensive faults kick in.

 

This winter would have probably killed the old battery anyway, surprised it lasted this long.