Morning All,

Just wanted to pick your brains....my car hit nearly 1.7 bar on the way home last night (foot hard down in 3rd), but has been mapped to run at 1.3 bar.

Question is, I know that my exhaust is leaking slightly from around the up-pipe area, will this be causing the boosting issue?

Nothing else has changed since the car ws mapped 2 months ago, and it still pulls as strong as it did before.

Any advice you could give would be great, whilst i'm waiting for my new gaskets to arrive.

Thanks

James

 

Anybody know if this will happen? or is there anything else that i can check?

 

I wouldnt have thought so, though if its letting air in due to a leak it could cause running issues (fooling the Lambda sensor), so I would get it sorted sooner rather than later.

Tony

 

Shame on you for still not fixing that leak!! If you've not had an issue with it over-boosting so far then it's likely to be something else, since hitting 1.7bar has it been doing that everytime you load it up in 3-4-5?

Graham

 

Would you not loose a slight bit of boost pressure with an Up pipe leak?

Surely if the combusted gases are not making all its way through the headers and up to the turbo, then the "leak" would slow down the rate the turbo would be expected to sprin, thus less boost. What about a actuator or wastegate issue?

Rob

 

Sorry Graham! The gaskets are sat in my shed ready to be fitted-not much good there I know!

Yes when i load it it will always go past the 1.3 that we mapped it to? Nothing else has changed though mate. Any ideas?

 

Hi Rob, how would I diagnose such an issue?

 

Id imagine it would just slow down spool up or the turbo....and the boost control then would just allow it to reach whatever boost its set too anyway I'd imagine.

 

I'd have to agree that the leak should slow spool not increase it. So check for split boost control pipework and any leaky hoses. Get that leak sorted and if it still is over-boosting then bring it up to me and I'll find the problem. Most common causes are splits in boost control pipework.

Graham

 

Hi Graham, sorry to hijack, but what if any problems would be caused by the downpipe to second cat delete pipe blowing? I have a slight blowing there!

 

Yeah will check for leaks and get the exhust sorted and take it from there, its probobly something really simple!

Thanks for your help as always mate

 

No a blow here shouldn't cause issues in terms of boost unless it's a huge leak, though it will definately play around with the flow going through the exhaust so you might find it's down on power.

Graham

 

Thanks for the reply mate, I'll get it gasketed if that is even a word!

 

Fear not! I have fixed the problem. Turns out I had replaced a section of boost hose with larger diameter stuff.... What a ****! Original pipe back on and back to normal boost - yippee!