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Discussion Starter · #1 ·
It's cranking for a while before it fires up but if I disconnect the coolant sensor it'll start fine...could this be a timing issue?

Obviously I could have it firing up all the time with the coolant sensor unplugged but I can't do that. It's also a working/new coolant sensor so I won't blame the sensor as it's reading fine.

Any ideas? i just find it strange how it'll start fine when warm/hot with the unplugged sensor so the engine must be willing to start if it thinks it is at a low temp.....but when it knows the engine is at 90ish it'll want to give me grief.......confusing. :)

This was never an issue before the head/injector change so why now? The pump was my original whilst the head and injectors were from another low milage PD130 engine.

Thanks
 

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Discussion Starter · #5 ·
I'm possibly looking at something that has been caused due to the change of the head/injectors then? Seeing as I can't change the timing via VAGCOM I might have to pop it into someone who can set the timing manually.

Cheers
 

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The ol' dears A3 had a problem starting when hot...after a bit of research it turned out to be the starter motor, of which is apparently a common issue on the 2.0TDi's. What engine code is your car?

Also, maybe it is simply coincidence that the problem has started after you had the other work done? (just a thought).

Either way, good luck on the fix [y]
 

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Discussion Starter · #8 ·
Cheers i'll look into those things.

Engine is an ASZ (1.9TDI). Thing is, after a 200 mile trip I can disconnect the coolant sensor and it'll start like a new car, with it connected it'll crank for a few seconds then start....but the coolant sensor is fine.

Give up, i'll just deal with it lol
 

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How do you know the coolant sensor is fine?

If its having problems with it connected but then is cured on removal then surely that means that the fault is in the sensor?

These are really common to give starting problems have you had it replaced?
 

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Discussion Starter · #11 ·
Yeah it was replaced and these issues have only started since the head was changed so you may be right or the problem may be within the injector pump or injector setup, even glowplugs?

As long as the engine thinks it's cold and fuels enough/heats plugs for a cold start there is no issue. When it knows the engine /coolant is hot it'll crank for a few seconds.

I can live with it but it's annoying to know that it's there. ;)
 

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Did you find cause of your hot start problems?

I've replaced the temp sender on mine and it's still struggling to start when hot. Starts fine if I disconnect it though.

If the crank sensor is faulty will it definitely show up with vag com? Any info on where to buy and how to fit a replacement?
 
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