Flat Engine, Low airflow reading <35g/s

[Rapido]

Driving back from Brighton on weekend and the car is completely flat, the turbo is not cutting in. I've tried the following:

1.Restart car
2. Check fault codes on VAG COM- Nothing
3. New MAF - Put on today
4. cleaned all electrical contacts on MAF and N75 etc

logging airflow only shows a peak around 35 g/s

Engine is AGU 1.8T Audi A3

Any help greatly appreciated.

Alex

 

[cupra-c_ya]

not so rapido @ 35 g/s, hope your turbo is not shagged? new maf has not made any difference to that 35 g/s reading?

 

[Daz_gibbo]

Sounds like it doesn't it. Or you have a badger trapped in your intake..

 

[Rapido]

Definately not so rapido. The car had a new turbo about 3000 miles ago. Its almost like an electrical connection is broken somewhere. Is there any readings I can check as I've got a multimeter.

Also theres no engine light on either but then I don't expect to in some ways. These earlier engines don't kick up much fuss in terms of warning lights on.

If the N75 was gone would it cause the symtoms I have?

Thanks

 

[Rapido]

I 've done a bit more investigating and there is no air flow through the intercooler into the inlet. There is also no airflow (sucking) with the metal intake pipe that sits at the back of the engine, after MAF etc.

As far as I can see there are no splits in any rubber pipes.

Therefore it looks like the turbo is effectively not working, does anyone have an idea what might be causing this bearing in mind the turbo is very new.

 

[Triple D]

I d say warranty job from where you got the turbo from me old mucca. I had a similar problem when i had my first hybrid blow. I had absolutly no boost what so ever, no power, it turned out that the vanes had seized in the turbo, 3 if the 4 bolts had either snapped or come out, so all the exhaust gasses where escaping before getting to the turbo. Turbo was fooked after closer inspection, so had to fork out £800 on a new one.

 

[gazjones]

could the dump valve be stuck open so no boost can build up or the wastgate is open all the time not allowing any boost to build up either if it was turbo you would have felt it go surley if you were driving

 

[Rapido]

I checked that out, but it moves fine. Its really strange drove all the way down to Brighton, car driving nicely full power and pulling well. Parked in multistorey did shopping came back went out didn't notice anything then as I went to accelerate I noticed servere lack of torque and slow revving

Its sounding more like a faulty turbo at the mo. I'll know more tomorrow

 

[Rapido]

update: Pulled intake pipe off to find turbo in one piece undamaged. However the compressor wheel was stuckin one position, it was freed easily by twisting with your hand. Once this was free it worked fine.

Took it for a test drive and full power was available again. Unforutnately got home parked up did some bits and went for another drive and it has faulted again. Same thing wheel just stuck.

I have spoken to the supplier who tells me it was a brand new turbo that has 12months warranty. Should be sorting another exchange unit today.

I presume there must be a high spot on the shaft/bearings thats causing this.

Something to bear in mind if any of you have these same symptons.

 

[Triple D]

Ah glad you have sorted it, but boy, they shouldnt be sticking like that at least you have warranty, like i did when my second hybrid blew up.

 

[Nath.]

probably a poor fitting bearing causing the compressor wheel to pick up on the housing

or just a dodgy casting on the housing itself