G60 Digifant Fueling Issues......Very Rich.

[Gti_Jamo]

Ok, spent a few hours this afternoon. First of the ecu vac line. It's on the nipple furthest to the top of the back of the inlet and assured its the correct orientation. It's in good condition and is 1m long. Checked all my earths and they are good, cleaned them all with emory paper when fitting engine. Even ran i direct earth from the battery to ecu with no improvents. Fuel rail is getting 13.9v, tested pretty much every component exept for lambda. I was however thinking that when my old engine melted a piston it chucked oil everywhere and drove it 4 miles home like this, could it be the lambda has been ruined or the cat is blocked. It's gets hot but it would do if it was running rich. Would've thought disconnecting lambda would improve matters but makes no difference whatsoever to engine tone or emmisions. I'm not sure how rich it supposed to be in 'test' mode but surely not this bad.

Cheers for the help guys, it really is appreciated.

[Ben@VWH]

Unplugging the lambda makes the ecu go into open loop fuelling, it will be slightly richer than normal but negligible difference. Lambda on g60's is only used to clean up the fuelling on idle and part throttle.

 Are you using the same injectors as you were before? Some pg with aircon had larger beige injectors, most had green tops, some rallyes had beige though. Basically is the chip matched to the injectors?

[Organisys]

As above, do you have factory fuelling chip and pulley size?

[Gti_Jamo]

Injectors are the original green tops. Charger has an 68mm pulley on it but not sure on the ecu chip. It's had it for 15 years though. Yeah the lambda supposedly takes over after 50 degrees but overridden at wide open throttle. Disconnecting it makes no difference when it's up to temp but i guess thats correct if its allready fueling like mad. That's the 3rd jerry can of petrol in it since saturday. Removed lambda and it's heavily bogged up with carbon deposits but i don't think that's my problem.  Cat still seems fine. Only time it doesn't overfuel is on idle with blue temp disconnected but will do once revved.

[Simeon]

Have you tried plugging the bts plug onto the black sender? BTS might be faulty, can't remember if you've replaced.

What ohms is your CO pot set to?

Are you 100% your static timing is correct? Make sure you use the flywheel tdc mark when setting it up

[Gti_Jamo]

Yeah swapped them round and even had a spare to try but still the same. CO pot at 500 ohms just now. Yeah checked timing loads of times and it's bang on via flywheel and cam shaft aligns with the mark on cam cover so no issue there. Also ignition timing is set to 6 degrees btdc at 2250rpm with blue sensor disconnected and up to full temp with fan disconnected. Although how accurate this will be with the overfueling present during the procedure i'm not sure. Even adjusting timing by hand while monitoring CO levels produced nothing positive.

[clipperjay]

I have an over fueling issue once with the dam hall sender the timing was well off!

[Gti_Jamo]

The distributor I have is only a few months old and genuine but i've yet to look into wiring going to it but did briefly remove the insulation to the connector today and I do have a conspicuous black wire thats spliced into the red wire going to the hall sensor connection and not present on wiring diagrams. I removed it and it still ran, but just the same.

[Ben@VWH]

This is going to sound like a stupid question but do you have the 30 ecu relay fitted? I had a corrado in once that had the relay missing and someone had tapped 12v in to the red hall sensor wire which back feeds everything to make it run, but very rich!

[Gti_Jamo]

Yeah checked that and the're all there. Need to investigate where it goes. I the immobiliser still works with it disconnected.

As for todays progress, back to the lambda sensor. I couldn't seem to get a decent reading from the signal wire although only  using a multimeter, it never went above 0.2v. So wipped it out and it was pretty choked up. Gave it a hit with some carb cleaner and fitted it with no difference. Think it hit 0.6v for a split second but other than that just switched back between 0.1 and 0.2v monitored and revs increased over a couple of minutes. Disconnecting changes the revs slightly and it appears to run slightly better, it eliminates the juddering of the engine, but still rich. Will the low voltage indicating lean running, the ecu could be compensating by chucking in loads of fuel fuel.