poor starting when warm vrs 2.0 tdi 170

[octaviam3]

hi, just wondered whether any one could shed some light on an intermitent fault with my 2007 octavia vrs 170 tdi.

It starts fine when cold or left for any length of time, but if i switch off the engine and try to restart whilst it is still warm,it just turns over and will not start immediatly, it can take a couple of minites some times. I have spoken to my local dealer who services the car and they suggest changing the fuel filter which i am happy to do,but i feel that this is unlikly to make any difference as when running the car drives fine.

also another problem i have with the car,is that sometimes first thing in the morning, especially in the winter,just after starting the car the overheating light and alarm will come on if i switch of the engine and restart it goes out and all is fine i was wondering if this maybe linked in anyway,I have also mentioned this to my dealer but they just seemed to shrug it off and told me that there was'nt anything to worry about.

[Wardy]

I'd say that would be a glowplug issue. Should be easily diagnosed if it is, as there's four of them (one per cylinder) and they can individually log faults on the ECU.

I presume the dealer ran a diagnostic scan on the car? But from what you say they don't seem overly bothered about the issue!

[octaviam3]

Thanks for your reply, I only phoned the dealer today to see what they would suggest i do, and they never even mentioned a diagnostics check,only that they would change the diesel filter. I will have to insist on a diagnostic check if the filter makes no difference.

Edited 15 August, 2011 by octaviam3

[Wardy]

When you take it in, ask if they think it could be the glow plugs, mention the reluctant winter morning starting, see what they say

[hoskurner]

I had the same problem with a PD140 i had, was fine starting from cold but struggled to start when warm.

Had the starter motor replaced and that solved it!

[Wardy]

Yep, another avenue worth exploring. A battery past it's best can also show the same symptoms sometimes.

Best starting with a check of any faults logged though, and go from there.

[octaviam3]

thanks,i will do that.

[Steve_Birdie]

I had the same and replaced the battery after finding that was faulty, then found that VCDS showed 2 glowplugs were faulty. Now thats sorted its starting fine when warm (only hope its fine during winter now-but i'll have to wait a few months to test that).

I have a 2005 1.9TDi PD engine 70k so a battery and glow plugs arent unexpected.

[Urpeth]

I drive a 07 plate 2.0 TDI PD VRS estate and have experienced exactly the same problem for the past 4 months. I’ve replaced DPF, had an early service and recently had x4 fuel injectors replaced (due to product recall), but the problem persists.

It has been suggested that replacement of the camshaft sensor might solve the problem.

Car starts perfect from cold, but needs to be cranked 5 times or more from warm and cruise control will never operate if excessive cranking has been required to start the car.

Any opinions would be welcome.

[silver1011]

When you take it in, ask if they think it could be the glow plugs, mention the reluctant winter morning starting, see what they say

The OP is experiencing warm start problems, he say's cold starting is fine.

Glow plugs shouldn't affect warm starting as they don't operate above a certain temperature.

There is a current thread at the minute regarding cold starting problems on the PD170 vRS, maybe the two problems are related?

[Urpeth]

The OP is experiencing warm start problems, he say's cold starting is fine.

Glow plugs shouldn't affect warm starting as they don't operate above a certain temperature.

There is a current thread at the minute regarding cold starting problems on the PD170 vRS, maybe the two problems are related?

Thanks - I'll post on cold start thread too.

[Urpeth]

Thanks - I'll post on cold start thread too.

Car had camshaft sensor replaced and seem to be running fine now. As a point of note, also had x4 fuel injectors replaced as product recall prior to camshaft sensor replacement.

[Jim1556]

Yep, another avenue worth exploring. A battery past it's best can also show the same symptoms sometimes.

+1

Mine really struggled to start when hot/warm, new battery solved it instantly - easy to check, warm the car up, stop it, then get another car (running), attach jump leads and start yours... Obviously if it still struggles to start then the battery isn't the issue.

Apparently the ECU looks for a minumum cranking speed before energising the injectors when warm, while it ignores the speed when cold...

Regardless if it fixes yours, its easy to eliminate as a potential cause.

Good luck!