Car overboosting, vag codes.

[PaulJC84]

Hey folks, my car is overboosting like mad. If i accelerate too hard the gauge will go round to over 25psi.

And if i am cruising at say 70 and move the throttle a tiny bit the car totally flies. But if I push the accelerator down too much will speed then like hit a wall and throw me forward.

I vag.com'd it today and got these codes.

16478 P0103 Mass air sporadic:
Flow circuit - G7
0 : High input


16716 P0322 Knock sporadic
Sensor 2
circuit bank 1 -
G66 : low.


I knew about the knock sensor a while ago so guess I just need to replace that.

But the maf code, do I need to replace the maf or could this be anything else.
I thought the overboosting was caused by the N75 until I saw that code.

Thanks guys.

 

[PaulJC84]

Just been out and taken a drive with the maf unplugged and the car drives a lot worse. Is almost like is missfiring and does not like uch boost at all.

Drives far better with it plugged in.

 

[Biglockie]

Bit OT but should the car run wth the MAF unplugged???

 

[PaulJC84]

Yeah if the maf is faulty and you unplug it the car will still run reasonably well, but obviously not as well as if everything is 100%.

 

[macca]

i'd say you boost valve or actuator is faulty, the over boost is causing pinking hence triggering the knock sensor, be careful you could blow a hole in your pistons or snap a rod.

 

[jcb]

you could have lost something as simple as a vaccum line to the Wastegate.
check all pipes for completion and leaks

 

[PaulJC84]

I think the knock sensor has been faulty for the past 3 years as when I got a map at star they said it came up.

So I think I will order a new one of those and a new N75 valve tomorrow and see if those sort it. I am also going to have a look at the hoses off the tip and check if they are all ok.

 

[Biglockie]

Mine stalls with the MAF unplugged is it knackered???

 

[PaulJC84]

Just a quick update, I fitted some new plugs and checked the hoses on the car.

I noticed that one was a little kinked so I chopped it and refitted it so it was straight and the car seem to be running a lot better.

It seems slow now though but is nice to have piece of mind.

 

[Markey]

Thats good mate, you might need to clear some fault codes and the plugs might not be as good as the Bks you had that could make it feel a tiny bit different.

 

[PaulJC84]

I fitted new bkr6e's was just time for them to be changed.

I think its because the boost has been lowered that it now feels slower.

 

[Markey]

I fitted new bkr6e's was just time for them to be changed.

I think its because the boost has been lowered that it now feels slower.

Oh ok, better put another hole in it then