Strange starting/running fault.

[sprogthedog]

Hi and thanks for letting me on the forum!

I bought a gti6 a couple of weeks ago, and over that time have been working towards getting her to mot standard (and undoing years of bodges).
I'm a mechanic by the way.

Anyway, it's developed a problem when starting.
It'll turn over and over until it eventually it coughs into life.
Also when being driven, if you give it some stick, about 5 seconds later it pops and farts like it's running out of fuel. It then picks up again.

I've replaced the in tank pump with no difference.

Anyone have any tips on where to look next?

To keep you all happy, here's some pics, cos we all like pics.

When I bought it

And now.

[Janne L]

I'd also suspect a fuel issue, either bad injector(s) or maybe an issue with the fpr?

[Redordead89]

Welcome to the club bud, Nice car!
There's an inline fuel filter under the car just behind/ below the door! Sounds like a blockage somewhere!
Also check out Janne L's car threads! (the dude in the above post)! Awesome Blaze GTI like yours ( a bit) lol

[insomaniac45]

I would have to agree, it def sounds like fuel starvation. It may turn out to be either FPR fault, or blockage in the system, which i would lean towards a blockage, as it is difficult to start, so i owuld imagine the fuel is having trouble getting to the injector rail.

[sprogthedog]

So, have replaced the fuel pump, fuel filter and spark plugs. All had no effect.
It's getting fuel to the rail and it has a spark.
It starts with a bump, but absolutely will not start off the key when stone cold.
Once it's had a run its fine.
Thoughts?

The wife (who is VERY tolerant) is suggesting doing an Elsa. ('Let it go'!)

[JTaylor2005]

Crank/Cam sensor? The one that controls the injection timing and spark timing?? Just a causual idea. Had similar issues with an old corsa I had and turned out to be crank sensor. (Not got much of an idea about these engines however :/ )

[sprogthedog]

Crank/Cam sensor? The one that controls the injection timing and spark timing?? Just a causual idea. Had similar issues with an old corsa I had and turned out to be crank sensor. (Not got much of an idea about these engines however :/ )

That's the thing, if it was crank or cam sensor, it wouldn't start. Ever.

It will not start from cold on the key.
Bump it and it'll always go. Run it for 2 minutes turn it off and it'll start first time.

Wierd.

[JTaylor2005]

Ahhh that's weird. I have had an intermittent problem with a crank sensor believe it or not. Would take forever to start and ran like crap sometimes. Other times okay. Took me 5 mins to replace all sorted. Could have been a loose conception etc. However those other symptoms you have said do seem to hint that it's something else :/

[sprogthedog]

SOLVED!!

JTaylor, it was the crank sensor.

Replaced and all is well with the world.

[JTaylor2005]

Brilliant good to hear

[cully]

they will start without the cam sensor
i forgot to plug mine in on first start when i installed my new engine doh!