Multiecuscan

So today i cleaned the EGR as the boost pressure sensor as well. They were still pretty clear, but despite that i cleaned them with some brake cleaner.

After that i made a test run again with the MAF connected and there's still a huge difference in actual and desired boost pressures till 3000 rpm. Above 3000 rpm everything is fine as usual.

Then i decided to disconnect the MAF and make a test run again. But disconnecting the MAF gives me less power on the whole powerband. I made a log with the MAF disconnected too and there's also the huge difference as with the MAF plugged in.

I did try to check some vaccuum hoses but they're not so easily to find (and follow). But i assume with a split hose i should have black clouds of unburned fuel? I don't, my car doesn't cloud much at all.

I now ordered a new boost pressure sensor and hopefully i can mount it next week.

IF someone has pictures of the hoses i should check also, they are really welcome!

Thanks again.

onnaj wrote:Can a bad boost pressure sensor also cause this?

Change the air filter, check the EGR (run this test when the car is cold. The EGR starts to work when the temperature of engine is >20 degrees).

I'll check tomorrow on my car, but mine is not a diesel model...

Right now I'm still thinking that is not a issue related to "wrong" desired boost pressure.
If it is the "desired" pressure, of course on low rpm's it's different from real pressure because exhaust gasses have not enough power to boost the turbo....

I mounted the new boost pressure sensor and made a new graph with ecuscan, but still the same problem.

It has noticable too little power beneath 1750 rpm.

I did a quick try and my case is the opposite of yours

desired boost is lower then actual...

I give up

Still no suggestions people?

Can the wastegate cause the problem? May it not open enough on lower rpm?

turbo charger starts working at about 1900rpm. Do not forget this

I've send my test file to some people and they all say this is the normal behaviour of the turbo charger. So there's no problem at all.