*RESOLVED* Fault Code(s) 0.4 Bar Max Boost = Constant Limp Mode!

[SalSheikh]

Mo, the guys i mentioned have a smoke machine to test for leaks

 

[Mo Arif]

Mo, the guys i mentioned have a smoke machine to test for leaks

Hmmm , I'll have to wait until I get paid for this now



Can small boost leaks cause this?

 

[Mo Arif]

Could a faulty ECU cause this?

 

[Pyro]

Small boost leak won't cause it mate I'd would imagine if there's a leak it'll be quite big get the logs done logging your boost and maf and go from there

 

[sambryant]

mo can you run some maf logs on vagcom. new mafs are also known to be faulty before they even get fitted to a car.

 

[Mo Arif]

mo can you run some maf logs on vagcom. new mafs are also known to be faulty before they even get fitted to a car.

I'm trying to but I can't even find anyone to sit me with to instruct when to start and stop the logs etc

 

[sambryant]

i know what you mean m8, i get my mrs to use the laptop

 

[DannyC87]

Small boost leak won't cause it mate I'd would imagine if there's a leak it'll be quite big get the logs done logging your boost and maf and go from there

Not sure I agree with you there. I have had this code numerous times. First was using a 50:50 valve, so only a small amount of air escaping. Second was a literal tiny leak around the map sensor, fixed it with bathroom sealant. Third was a small misalignment of the throttle body.

Have you had the TB off? Did you fit a new gasket when you refitted it?

 

[Mo Arif]

Not sure I agree with you there. I have had this code numerous times. First was using a 50:50 valve, so only a small amount of air escaping. Second was a literal tiny leak around the map sensor, fixed it with bathroom sealant. Third was a small misalignment of the throttle body.

Have you had the TB off? Did you fit a new gasket when you refitted it?

I haven't taken the TB off but I did clean it with carb cleaner

 

[DannyC87]

I haven't taken the TB off but I did clean it with carb cleaner

That shouldn't be the problem then. It doesn't have to be a huge leak for the ECU to pick it up and throw limp mode.

 

[Mo Arif]

but this is hard limp mode, it won't come out of it! I only get the following fault code:

17705, which I've always had when it was boost to 1.2-1.4 Bar

 

[Pyro]

Not sure I agree with you there. I have had this code numerous times. First was using a 50:50 valve, so only a small amount of air escaping. Second was a literal tiny leak around the map sensor, fixed it with bathroom sealant. Third was a small misalignment of the throttle body.

Have you had the TB off? Did you fit a new gasket when you refitted it?

Fair play then I had three Leaks In the IC pipework but never got limp lol guess each cars different lol

 

[DannyC87]

but this is hard limp mode, it won't come out of it! I only get the following fault code:

17705, which I've always had when it was boost to 1.2-1.4 Bar

you have fitted your n75 the correct way round haven't you??

 

[Mo Arif]

Yes mate, it's the right way around

 

[aviaa25]

how many milles your car at?
i think its your n249 bypass

 

[Mo Arif]

70k clock the clock FULL DEALER SERVICE HISTORY

 

[aviaa25]

try to reinstall the n249 and check for error..
i think that something with your bypass go wrong.

 

[Mo Arif]

this is what I have done for the removal:

 

[LEE69]

Noting wrong with that bypass as long as you put a bolt in the pipe that was originally going to the dump valve.

 

[Mo Arif]

put a bolt in both the orange / yellow pipes