Modified URS6 running rich

[twoqu]

You could verify that the car has enough vac by connecting /disconnecting the fpr rather than producing it manually. We are looking for a 0.5 bar difference.
Perhaps the 044 is a poor choice and an alternative such as Walbro might be a better compromise. Wonder if the pump was done after the mapping.
The info about the Maf is worrying but that was always a concern. So its useful to have confirmation.
Dmitri, is the only way to assess the maf signal by the measuring block in the basic settings using VCDS? I seem to recall you stating a value previously.

[prj]

Block 000 at idle, there is a value for load yes, but without knowing if it is on ADU base chipset or AAN base chipset this is kinda useless.
Not to mention if there are leaks...

If it was boost tested properly with the manifold connected, then problem is elsewhere, if for some reason the TB hose was removed (no idea why people do this), then nothing was tested essentially except for the intercooler piping.

[S4Marc]

I think it's only fair to admit when you make a mistake or are wrong

I did not do the pressure test last week thoroughly enough

Apologies if anyone feels I've wasted their time but I'm openly honest and learning as I go


Currently working on the intercooler system (MAF to throttle body) first and desperately trying to seal the turbo snail housing which seems to leak far too much

[S4Marc]

A new day and new approach, I've done quite a bit this morning but unfortunately I'm no further on. I will post my results and hopefully someone can decipher them

1) Changed the FPR for another used item and the pressures were identical........4.2bar vacuum 5.2bar atmosphere

2) Changed the MAF for a known working one but alas the CO reading hasn't changed at idle or a steady 2.5krpm

That means those two areas can be forgotten about for now


3) Pressuse tested the TB onwards with 15psi using highly accurate refrigeration gauges and nitrogen. There is air coming from the catch can vent and two extremely tiny leaks on two injector seals

Catch can vent blocked off, 15>0 Psi lasted 50secs

Catch can left alone, 15>0 Psi 29secs




Awaiting different bungs to test the turbo and intercooler system but it does seem the Garrett turbo compressor housings do leak from factory

[prj]

It depends how much it leaks. If it's not sealed right, there can be a massive leak.
15->0 30 sec is fine, the turbo produces so much that this is irrelevant.
I recommend pressure testing the whole system always though.

[S4Marc]

Managed to adapt some pipework and pressure test the turbo inlet to TB

15>0 Psi 27secs

I could see air leaking from the compressor to turbine housing and hear it escaping down the exhaust pipe

At 15 Psi the N75 wastegate frequency valve started to leak heavily where it would connect to the inlet pipe, unsure if this is normal. During the test I blocked this pipe with my finger

[newsh]

Ok good info.

I actually had the cold side of my GT30 come loose and run like that for a while, I thought I was hearing surge .. duh

30 secs leakdown of the full inlet tract is not too bad.
If you block the breather connection at the MAF hose (not sure if you now have it connected there or not) and the small one way valve under the IM is removed and the IM connection blocked off, then the only way to pressurise the crank case is past the rings.

Fuel pressure..
Is is possible you have a restriction in the return pipe to the fuel tank?
Or damage to a fuel line under the car?

I think I would disconnect the return at the fuel rail, pipe it to a fuel container and see if the fuel pressure is still higher than it should be.

[newsh]

Managed to adapt some pipework and pressure test the turbo inlet to TB

15>0 Psi 27secs

I could see air leaking from the compressor to turbine housing and hear it escaping down the exhaust pipe

At 15 Psi the N75 wastegate frequency valve started to leak heavily where it would connect to the inlet pipe, unsure if this is normal. During the test I blocked this pipe with my finger

This should not leak, is it connected the right way round?

The base of the T goes to the face of the turbo.
The long leg goes to the MAF hose

[S4Marc]

Should I try with the replacement MAF on for a longer period of time so the ECU can learn? I plugged the replacement MAF in then carried out a CO test immediately

I will remove the return fuel line in a minute and see what the pressure does


I'm hoping to connect VAGcom later

[twoqu]

Is there any evidence that the fuel pump was fitted after the mapping, from invoices or dyno date. At the very least that would put a spanner in the works of putting it back to stock for Mot purposes! We know now that the fuel pressure rise is down to the 044! So there is 1 bar difference between atmo and vac? So down the line either an adjustable fpr or different pump might be needed IF it was indeed mapped for 4 bar base fuel pressure. If it was a little bit leaner then it would probably sneak under the idle CO limit at least.
Still think a more detailed explanation of the breather system would help as if nothing more it looks odd particularly that loop from the cam cover.
Try to get the vag com on it and see what if any faults there are and look at that load value. Then remove the power to the ecu via the motor fuse for 30 secs which should erase anything stored including the adaption i believe. Reconnect vag com and see if anything has changed. Then do the same again with the other maf. If nothing else that will allow a comparsion beteween the Mafs in terms of the load value. I appreciate we don't know which range it should be in.
What does the car idle at out of interest? Does it have a recirculating dump valve? Is it the stock plastic end tanked intercooler?
Sorry more questions than answers I'm afraid!

[diesel des]

[QUOTE=prj;2031540]
Be careful at WOT because of too high fuel pressure? Care to elaborate exactly what it's gonna do apart from being down on power?

Dimitri, I had said be careful testing with a new fuel pressure regulator with less pressure. Read what I said. No need to be awkward. I reckon closer to a 20% reduction in fuel moving from his faulty 5 bar regulator to a working 3.8 bar. That could solve his issues as his system looks leak free so far. That or it's the MAF.

Sent from my Moto G (5) using Tapatalk

[newsh]

Pretty sure the car was mapped with the 044 pump. You could check with Pete Berry.

[newsh]

I believe the weird pipe on the PCV system has been removed and the PCV reconnected to the MAF hose.
The one way valve has been removed.
I’ve lent him my MAF which has made no difference (I believe the ECU will react instantly to a good MAF but certainly pulling the ECU fuse or disconnecting the battery would reset the ECU adaptation and clear any stored codes.
When I had bad contacts at the MAF connector it would run better for a while after disconnecting the MAF and resetting the ECU

[S4Marc]

Pretty sure the car was mapped with the 044 pump. You could check with Pete Berry.

Correct

[newsh]

I’ve just bumped the MAF connector thread