non starter - 8v digifant over fuelling

[zinderz]

Hi,

Having finally got the mark2 running sweet, went to start it today and nothing. It turns over but won't start. Getting a spark, changed plugs for brand new ones, and still no change. However, if the engine is cranked with the plugs out, fuel shoots out of the bores, like a lot. Any ideas on the problem? ECU issue? fuel pressure regulator?  Had the AA out to cast their opinion, and he did the usual checks, HT leads etc, but couldnt diagnose the problem other than over fuelling.

Please help!

Regards,

Jerry

[fused]

If the MAF was buggered could that fool the ecu to deliver too much gogo juice? (is there ever too much gogo juice?  )

[Jay]

Yes they can over fuel if not setup correctly, which means loss of power.

[ToddyGTi]

Hi,

Having finally got the mark2 running sweet, went to start it today and nothing. It turns over but won't start. Getting a spark, changed plugs for brand new ones, and still no change. However, if the engine is cranked with the plugs out, fuel shoots out of the bores, like a lot. Any ideas on the problem? ECU issue? fuel pressure regulator?  Had the AA out to cast their opinion, and he did the usual checks, HT leads etc, but couldnt diagnose the problem other than over fuelling.

Please help!

Regards,

Jerry

When you turn the ignition to point 2 does the fuel pump prime and stop or does it continually run? It should stop.
2nd I'd suspect the AFM so swap it with one of a mates motor that works and see how that goes. Otherwise it could be a timing issue, have checked the timing recently?

[zinderz]

Fuel pump primes, then stops as it should. Haven't checked the timing recently so this could be a problem. It had overheated and I have suspected that the fan wasn't coming on depsite the engine getting hot enough. So perhaps a coolant sensor issue? I've heard this affects the fuelling aswell?

[ToddyGTi]

Fuel pump primes, then stops as it should. Haven't checked the timing recently so this could be a problem. It had overheated and I have suspected that the fan wasn't coming on depsite the engine getting hot enough. So perhaps a coolant sensor issue? I've heard this affects the fuelling aswell?

The coolant sensor does control fuelling but it would allow the car to start and then it'd run like a piece o crap. I'd change your AFM for one thats known to work. If you're local to Kent you can one of mine, I have about 5 of the bloody things!

[zinderz]

I'm in Portsmouth but appreaciate the offer mate. Think I'm just gonna book it in with a specialist and see what they reckon. Cheers for the help guys.

[DarnPB]

Check that the return-to-tank fuel line is not blocked or the rigid pipe is not kinked or squashed. Injected engines have too much fuel delivered to the engine to maintain fuel pressure, and the excess fuel gets returned to the fuel tank. If the return fuel lines are damaged or there is a restriction, then the excess fuel has no where to go except to the engine.
Also check the fuel pump relay. That is, or used to be a very common fault with VAG.

[Mr Blue]

Thats the ignition moduel that sits ontop of the ECU. about £40 new i think they are.

My bets on the ignition mod

[ben44]

has the earth strap from the battery to gearbox snapped, if so its killed the ecu and it will just fill the bores with fuel! this is sooooooooooooooooo common!