MAF sensor & N75 Fault's (Fault Codes Inside) - Mk3 Ibiza Cupra 20VT

[Wilksey]

Hi guy's

Recently my car went into limp mode, after doing a stationary VAGCOM diagnostics which showed me aload of fault codes we decided to run a rolling diagnostics to test the MAF reading and boost levels. After completing the test we had a look at the readings produced to find the MAF sensor was reading 'zero' the whole way through the recording. This to me indicates that the MAF failing has caused the car to go into the 'limp mode'. Is this a common problem on th3 1.8 20VT engines. May I add that I have just had a look at the trouble shooting guide and read up that if the car has an open cone filter the MAF sensor can become blocked with oil and dust which causes the sensor to fail. My car has an open cone filter. I also read that increasing the size of the turbo can also cause the MAF sensor to fail as the airflow reading is much higher than it origionally was. Again my car has the uprated K03s turbo. Both indicating the fail of the MAF sensor.

Also there was a fault with my N75 valve which im yet to look into properly. I was advised to check the common faults with the car before proceding so in doing so I took the N75 valve out hoping the ECU will revert back to the previous map and increase it's boost inacordance. But to no avail the car still only boosted at 0.4 bar instead of 1.5 bar. Does this indicate that the N75 is not faulty or is it worth replacing if the code keeps coming up even after deleting?

Here is a copy of the VAGCOM fault codes. Please can anyone shed any more light on the situation as I've seemed to have narrowed it down to possibly the MAF sensor or the N75 and not what was thought to be a boost leak etc etc etc and if yourself or know anyone that has experienced any similar issues as I'm pretty fed up of driving on low boost!

Many thanks in advance for any help and advice

james


Here are the faults listed by VCDS...

Wednesday,07,July,2010,18:28:31:46868
VCDS Version: Release 10.6.0
Data version: 20100630



--------------------------------------------------------------------------------
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Address 01: Engine Labels: Redir Fail!
Control Module Part Number: 6K0 906 032
Component and/or Version: 1.8L R4/20VT SEA 0002
Software Coding: 11500
Work Shop Code: WSC 00000
VCID: E5CA2CDB5509
12 Faults Found:

17833 - EVAP Purge Valve (N80): Short to Ground
P1425 - 35-00 - -
17955 - Boost Pressure Regulation Valve (N75): Short to Ground
P1547 - 35-00 - -
17843 - Secondary Air Pump Relay (J299): Short to Ground
P1435 - 35-00 - -
17829 - Secondary Air Injection Solenoid Valve (N112): Short to Ground
P1421 - 35-00 - -
17697 - Boost Pressure Control Valve (N249): Short to Ground
P1289 - 35-00 - -
17525 - Oxygen (Lambda) Sensor Heating Circuit: B1 S2: Short to Ground
P1117 - 35-00 - -
16486 - Mass Air Flow Sensor (G70): Signal too Low
P0102 - 35-00 - -
17522 - Oxygen (Lambda) Sensor; B1 S2: Internal Resistance too High
P1114 - 35-00 - -
17524 - Oxygen (Lambda) Sensor Heating; B1 S1: Open Circuit
P1116 - 35-00 - -
16518 - Oxygen (Lambda) Sensor B1 S1: No Activity
P0134 - 35-00 - -
18010 - Power Supply Terminal 30: Voltage too Low
P1602 - 35-10 - - - Intermittent
16524 - Oxygen (Lambda) Sensor B1 S2: No Activity
P0140 - 35-10 - - - Intermittent

-2Readiness: 0010 1101

 

[s1l3nc3r]

Just a hunch but have you checked your fuses...a few short to grounds there normaly point to fuses.

 

[R4cup]

If your maf is reading zero u can try mine. Im up your way Sat if your about, shoot me txt.

 

[Wilksey]

Alright Ryan (R4cup) I'm working Saturday till 5pm. Will you be about between 5.30 and 6 on Saturday? If not I can see if I can shoot out on my dinner hour or Sunday if not? I'm 75% sure it's the MAF but need someones for 15 mins to check before buying a new one! I'll text you mate. And S1I3NC3R, the lad who had the car before me made a bit of a hash with the N112 and N249 bypass, the 2 valves are still in place hanging around in the engine bay. If I was to connect a resistor to each valve (the n112 and n249) should that solve issue?

 

[s1l3nc3r]

If you want to compleatly remove the n112's then if you cut them off and put a resistor in there place then there should be no problem.

Re-route the dv feed to the mani and block off the others and you should be fine.

But thats not going to clear the codes you have at the moment. from the looks of it id say a fuse has gone some where...

Just out of interest did you clear the codes and rescan it to see if they all came back up again...?

 

[Pigeon142]

I checked the codes for Wilksey, yes I did clear them and they came back straight away. I have had suggested to me by two people that it could be the fuel pump relay???

"Good bet that's a faulty fuel pump relay. It's a 40 amp beast and supplies all the listed components.


Agreed. "

Worth a try??

 

[Big_daddy]

Check fuses.........

 

[Pigeon142]

Was a blown fuse.

Wilksey hope you are enjoying the boost!

 

[R4cup]

Was a blown fuse.

Wilksey hope you are enjoying the boost!

After all that, glad we got it sorted

 

[Pigeon142]

I know it would have bugged me otherwise. All Wilksey has to do now is sort the oil on the intake!

 

[s1l3nc3r]

So it was a fuse then... I don't want to say I told you so but

glad you got it sorted now though.

 

[Wilksey]

I just want to say a big thank you to pigeon 142 and r4 cup for helping me out big time trying to sort the problems out!! nice one guys.