How to see if ones engine is on limp mode???

[Vauhtiveikko]

Will do that tomorrow, it is very nice to have good advices from You PRJ, I really appreciate it!

What do you think, should I replace the knock sensor (G61) or could it just be reflection of something else? (That code has pulled up two times now.) We have those knock sensors at work in stock so I can easily get a new one.

Edit:Answered already on previous page, I will sort it out ASAP.

[prj]

Well, it can either be the knock sensor or the wiring to the knock sensor.
Make sure you correctly torque the knock sensors as well, that is very important for correct functionality.

You can check the wiring, if that is okay, then I guess you need to replace the sensor.

Good luck.

[Vauhtiveikko]

The connector looks fresh, but have to check the rest of it. The correct tightening torque should be 20nm I think.

[UrS4boy]

G61 and G66 Knock Sensor info

The connector looks fresh, but have to check the rest of it. The correct tightening torque should be 20nm I think.

Here is some G61 and G66 Knock Sensor info. Torque is 20 Nm (15 lb-ft) as shown here:

http://forums.quattroworld.com/s4s6/msgs/113032.phtml which is linked out of this general G61 & G66 post:

http://forums.quattroworld.com/s4s6/msgs/21047.phtml

[pasbogdan]

Was ignition on when you cecked your knock plug?That may be why it says "no signal" and intermitent.

How will ecu react when a medium boost leak is present?Will change n75 freq trying to let less air to get to wastegate and try to obtain target boost?But how much is abble to do that before getting into limp mode?

[Vauhtiveikko]

Been working too much this week so did not have the time for my baby until this evening.

Changed the knock sensor and then started to hunt for leaks. Found the ISV leaking quite alot from the end of it, so I glued it with Sika (will have to see if it lasts, have to dry overnight). The bigger airloss were found at 1,5bar from the ECU pipe entering the ECU inlet. Also changed the pressure gauge insert that was made together mostly by electric tape

The moisture trap inserts seemed Ok so I left them alone. When checking other vacuum pipes I managed to break a tip off from the plastic charcoil canister backpressure valve. I changed it to a metal version and I think it will work just fine.

The judgement day is tomorrow, when I can pressure test the ISV again and then fire up the engine. I´ll hope these findments will make a difference.

[Vauhtiveikko]

Got it back to one piece again, drived the engine warm and pulled the logs:

Sunday,13,November,2011,10:55:12:29542
VCDS Version: Release 11.11.0 (x64)
Data version: 20111111


Address 01: Engine (8A0 907 551 B)

10:55:04 Group 000
206
021
072
131
076
132
048
129
127
033


10:55:04 Group 001
720 /min RPM
95.2°C Temperature
1.008 Lambda Factor
11.3 °BTDC Ign. Timing

10:55:04 Group 002
720 /min RPM
2.21 ms Inj. On Time
13.94 V Voltage
1020.8 mbar Absolute Pres.

No fault codes anymore, but I still think there is something wrong in the picture.

How much will the booste gauge hose affect to the ecu information if the t-piece connector is the same size in every direction? In my wifes 1.8T passat the T-piece has a metal inner tube that makes the airloss smaller to the gauge direction.

Edit:I ordered a new RS2 maf gauge that should arrive on thursday, so we will see if that helps the Go.

[Vauhtiveikko]

Changed a new RS2 Maf to the car and did some test runs after that Feels much better now and the boost is holding in 1.5bar with a peak of 1.6ish

Noticed tho that the bypass is now making louder woosh sound when changing gear. I´ll have to check for that next.



The old MAF did have a crossed tube extension on it fitted with duct tape. I think it was there to control airflo but I did not put it on the new one. Does anyone else have one on the MAF?

[prj]

WTF? That thing is not needed there for sure.

I hope you are using the original airbox. Fitting a cone filter next to the hot exhaust manifold decreases performance on these cars.

Your group 000 log should look better now as well. 21 was too high with RS setup.

[Vauhtiveikko]

I think so also, looked like a science project of one sort the patent, so it was time for it to go

I made some logging today but somehow managed to lose the results in my computer. To do list got longer because i found out that according to group 3 the T.B. angle got on it´s highest to 76,3 when I floored it. Have to check the TPS and measure the clearances and values... mayby no overboost for me now...

[prj]

I think so also, looked like a science project of one sort the patent, so it was time for it to go

I made some logging today but somehow managed to lose the results in my computer. To do list got longer because i found out that according to group 3 the T.B. angle got on it´s highest to 76,3 when I floored it. Have to check the TPS and measure the clearances and values... mayby no overboost for me now...

You know it can be something really silly like the cable being misadjusted.
Usually it's that.

Good luck...

P.S.
You can adjust the TPS without running the car. The reading shows up even with only the ignition on. It's done on purpose for diagnostics.
Soon you will be a pro audi fault finder

[Vauhtiveikko]

POWER

PRJ I will offer you few beers if You visit Finland!!!

The throttle cable was about and 1cm offset, so the 75,6% was seen in the TPS. Adjusted the cable to right position and now I can see 99,9% in the measure group and also full boost (1.8bar) and it holds 1.5bar´ish to the redline. Goes like crazy now

The gremlin has been there since I bought the car because I havent adjusted the cable even when i changed the injectors and detached the cable

Now it´s time to enjoy before the snow kills the g-forces and the going gets sideways

[prj]

Ha!
I am glad you got that sorted

Yes, I have fixed a few cable problems in the past.
I have never seen a TPS fail yet, all problems for me were solved with cable adjustment or soldering through all the contacts in the TPS plug.

Have fun with your car.
Boost is a little high for these injectors, I recommend you to log IPW/RPM (Group 002) with VAG-COM during a pull and see how your IDC is like, especially towards redline.

[porkkis]

I always check the throttle cable when remapping. I've scrached my head too many times with "why doesn't this pos car boost".

If you're not using the factory air box, some sort of flow laminarising unit is a good idea. I would use the part that was there.

[Vauhtiveikko]

If you're not using the factory air box, some sort of flow laminarising unit is a good idea. I would use the part that was there.

I am using stock airbox with orginal paper filter AND RS2 maf. I have flexi pipe from the oilcooler duct to the airbox for extra air.


I will do some logging when the ground melts again, today was too slippery to apply full force with summer "slicks" (was -10 degrees last night).

If the injectors would be on their limits, would it help enough to boost the fuel pressure with new, better fuelpump?