8v Digi - Not Starting.

Has anyone ever had the starter motor off the car, maybe its been refitted upside down which would have the low side volts going the wrong way.
you could also look at the starter motor speed regulator under the dash, it may need turned up to 1500 rpm which will help the fuel pump kick in
Not very common but Knock sensor could be lose and not feeling the crack of the starter motor to tell the ecu to to send 12 volts to coil
which would explain the bump starting ..even a lose sensor would pick this up
But do not over tighten or you kill them 20Nm

 

I know what Adam Hills would say about that post. lol

 

Looking at the topic again I had a stab at thinking outside the box and thats what I came up with

 

Guys sorry the late update and appreciate all the replies above

The Mk2 is running ok now. Turned out to be the blue temp sensor causing the non starting issue.

Strange eh......

 

More than likely the case Jonny

I haven't seen the car since Saturday, but will take a good look at the plug and the old sensor just to make sure.

 

Well done John, well done Richard.

 

Thank god its fixed

 

Me too.

Wouldn't of thought this sensor would cause starting issues really, but you live and learn I suppose.

 

Still shouldn't have started on a bump if it didn't on the starter at normal cranking....duff sensor or not.
But yes You do learn and I have ......waste of time trying to fix cyber sh ite that's not in front of me.......think of the time & money people could save if the just took the car to a mechanic!

 

There is only one mechanic I trust. The guy who does my MOT's who I travel 20miles to. That's how bad I am.

When a mechanic comes over with a diagnostic reader to plug into a standard MK2 8v GTI, that's enough to put you off mechanics for life !! lol

 

Have you got the blue sensor that came off it?
If so, what resistance does it have at room temp?
Imagine John's right, and it has a failed contact inside, that would make it 'look' like it was really, really cold (high resistance), and the ECU would fuel at maximum cold enrichment, which would be too much, flooding it if attempting to start with the starter.
With a bump start though, no airflow/no fuelling until the moment the clutch is released, so less chance of flooding, despite the crazy-rich mixture?

Just an idea, might be as useless as my last...