G40 fuelling problems?

[Andy]

It's also worth following the advice in this guide:
http://www.polog40.co.uk/forum/index.php/topic,214.0.html

Check the basics first, and go from there.

[electricpanda]

Thanks for the reply.

[grungeisdead]

if you can confirm the make of the cam, I may be interested in a swap, as it might be suitable for my turbo conversion. I have a piper 272 cam which was made for a polo G40 with a G-Lader, its been fitted but never used and I have the original reciept for it.

[electricpanda]

It's a Newman 264/268 G40 fast road cam.

Also Before the cam gets swapped tonight back for the standard g40 cam, will it be a noticeable difference or is it not worth the time to change it?

Thanks

[scotsjohn]

Obviously at odds with some of what's been said already, but I've a Newman "fast road" cam fitted and am quite pleased with the noticeable mid range pick-up. Newman advertise this cam specifically for the G40 and aren't pushing it for it's top end power. At 264/268 it can't be all that far away from the original cam's dwell and they've probably not altered lift very much if at all. I wouldn't write it off too soon.

[electricpanda]

Ok, I'm starting to get somewhere now. It looks and seems like its the ignition timing. The knock sensor is fine, I've done most of the basic diagnostic checks and all is well.

I spoke to the VW specialist who fitted the chip and he confirmed this was after all other mods. Running issues started pretty much instantly after this and we're thought it just needed fine tuning to solve.

Can anyone think of any other reasons before I get another map?

Thanks

[Andy]

What injectors does it have in it?
Have you checked the fuel pressure?

[electricpanda]

There Bosch ones I think. 250cc

[electricpanda]

Disconnected that blue sensor tonight and it still did it do reconnected. The lead running into it is labeled as "Knock" from when whoever put the engine in did the looms. It's a 3 prong plug. Possible it's in the wrong place? Looks like the wire runs past the inlet. If it is wrong where should it go?

Thanks

[Andy]

Blue temp sender should have a blue 2-pin connector going to it.
Knock sensor has a 3-pin connector, and the wiring harness is shielded cable, so it's easy to identify.
Check what's plugged in to your throttle body switches (white connector), and what's plugged into the CO pot/air temp sensor unit in the boost pipe.

[electricpanda]

The one on the pipe at the very top and back of the bay (assuming its the blue one as has a blue circle on it) is a 3 pin connector and has a lead labeled knock, it's a thick black wire which runs down past the fuel rail.

I'll have another look at what you said.

Thanks alot

[electricpanda]

I don't know if this is possible but looks like the co2 pot on the boost pipe has the knock plugged into it. Where should it be connected?

I'll try swap them round.

Thanks for your help

[PeteG40]

knock sensor bolts to the back of the block - but often the end has a 'holder' which is bolted to the inlet manifold

[electricpanda]

Thanks Pete.

The Knock sensor comes off the block and into the port on the boost pipe, theres one lead on the inlet bracket and that is a 2 pin one.

I'll go have another look.

The throttle has the white one.

Thanks.

[electricpanda]

Biggest help would be if someone knows what the wire/connector looks like that should go into co2 pot