I Have A New Toy............. URS4 Avant

[twoqu]

When you say driving with speed sensor unplugged do you mean the VSS? So the ecu does not know the car is moving?
I think the VSS signal is important to both the LC system and ICV system.

[prj]

When you enter ECU with vag-com it will directly say if it is my software or not...
No need to pull it apart.

Again - launch control can not cause it to cut out at 2000-3000 rpm under load regardless of sensor readings, so just stop exploring this.
I wrote it and I know exactly how it works.

The fact that it happens under load means either that there is no fuel pressure at all under load or there is some sort of RF/EMI.

[Sleeper_Avant]

I checked fuel pressure today,
also bought a new laptop and took some more readings from VAG-COM.

and a few videos, once they upload.

PRJ, I also do not think it is launch control, it cannot be.

It does indeed have your software, stage 3 as stated.
I am happy to speak to you via PM if you want, no need to mention your software on the thread when it is clearly not the issue!

I will reply with some links soon

I do have questions about VAG-COM measuring blocks, I know there are limited items to view but what can I actually look at?

from what I can see, all inputs are perfectly within limits

Cheers Folks

[Sleeper_Avant]

Photobucket strikes again and missing loads of pics and videos!

But here is a few for now

Is the arrow meant to flow from ECU to manifold?





ECU plug I have already had apart, no issues found so grased and refitted, hence why it looks like this.




Injectors currently fitted to the car, 440cc/min, still unsure of what pressure that is at but I will check now.




New laptop thing, only £179 so worth it for my car stuff.





Took fuel pump out, no markings but was changed for a genuine Walbro by previous owner
few issues with the pump fittings but now sorted and nothing to cause my issue

[twoqu]

Yes the first picture is the moisture trap which should be connected inline between the inlet manifold and ecu. If its been like that all along then presumably the ecu has only been seing atmospheric pressure not vac/boost!

[Sleeper_Avant]

Right then, live data I took, no pics as photophucket put a stop to it lol!


Tickover 890/940rpm

1.75/2.0mS injector timing

0.6 lambda factor

60psi fuel pressure

At point of holding back 4500rpm:
85psi fuel pressure
Approx 15psi boost, about right fuel pressure?
Timing 12degrees BTDC (I think, although that could be on tickover, I might have wrote it down at the wrong point)
Lambda 1.000
Load 0.00 ?

R201 measures 5.61ohms when just been running

I am at a loss here to be honest

Blocked Exhaust?!
I has got a brand new huge expensive system so cannot see it but you never know,

Just to clarify,
non genuine MAP sensor and R201 Have been changed
Running 4 bar FPR
NEW cam and RPM sensor
tried new FPR, no difference

that's all for now

Any ideas on what MAP and MAF readings should be voltage wise?
I can measure with an oscilloscope so no issues there.

[Sleeper_Avant]

Yes the first picture is the moisture trap which should be connected inline between the inlet manifold and ecu. If its been like that all along then presumably the ecu has only been seing atmospheric pressure not vac/boost!

I know its the moisture trap Twoqu, and running a vac line to bypass it today was on my list of things to do today,
Sadly my virus/Mumps came back with a vengeance over the weekend and I just couldn't manage another minute with the car.

I will build ECU back up and do a before/after test with moisture trap bypassed

I really really hope it is something that silly!

Off to bed now with Lemsip,
will report back tomorrow

Oh also will most likely be why it doesn't generate much boost I'm guessing

Thankyou

[twoqu]

The idle should be nearer 800 +/-30 unless you have the aircon on or its been raised in the sw.
Lambda should be around 1.0 at idle. Lambda is closed loop at idle basically.
Fuel pressure should be base + boost so it seems its over by 10psi.
Most of the base settings are based on the assumption that the engine is at its set idle speed so its hard to compare.

[newsh]

Lambda 0.6 is ridiculously rich but you would only see that on a wide band

[Sleeper_Avant]

Couple of vids I stuck on youtube:

https://www.youtube.com/watch?v=Sx0dUii3I4A

https://www.youtube.com/watch?v=TfOx0Hou4JA

You can clearly see the point that it just backs off and holds back, no misfire, no rev limiter, just struggle to gain any more engine speed

car is in 6th gear with load.

[piotr]

Is this wheels free run(wheels of the ground,on the rump)?

[prj]

Does the issue actually happen on the street?

Can you put a piece of metal pipe into the inlet hose between the turbo and the MAF? I think it might be collapsing then starving the engine.

[Sleeper_Avant]

Prj, i only noticed when it was driven for the first time ,

I will put that on my list of things to do today and report back

[prj]

Yea or try running it without the air filter and see if the issue still occurs.

[twoqu]

Didn't the PO say the problems started after it had been laid up? Perhaps a rodent has made a nest in the airfilter housing or such.