Thread: Increased power TD5's - what have you done to solve the MAF issues?

Yes the bloody MAF!
I have run mafless for years with no issues whatsoever.
I run a mild tune with uprated MAP sensor and have done over 80k without the MAF connected.
Actually gutted an old one by removing all restrictions within the housing and also all the pins in the plug receiver.
Keep it ‘plugged in’ but no impact on fuelling.

Economy unchanged, runs smoothly and considering a lot of diesels from the td5 era ran with a MAP or MAF but rarely both and the fact that the ecu looks at both is good enough for me.
Yes there is no fall back if the MAP fails but really how often do MAP sensors fail?
And I carry a spare anyway!

A few failsafes may not be in operation without the MAF but I will let my right foot decide whether I blow the engine or not.


It is a manual though and I have read of issues with autos if no MAF, maybe more to do with the boost modulator? Don’t know on that one....

Paul.

When installing a VNT the Discovery 2 turbo boost modulator is disconnected and bypassed (can be removed).

You are correct that with the automatic transmission there is no drop in boost during gear changes.

Originally Posted by twr7cx

When installing a VNT the Discovery 2 turbo boost modulator is disconnected and bypassed (can be removed).

You are correct that with the automatic transmission there is no drop in boost during gear changes.

And if you tee in on the inlet manifold instead of the turbo outlet pipe it gets even better!

IMO the gist of the whole story is that for a VNT/VGT turbo a properly addapted fuel map and higher end MAP sensor is needed cos the whole ''matrix'' is mixed up as a "foreign" element was introduced into an algorythm which was conceived for something else... even the fact that the wastegate modulator becomes futile is not OK cos it's an integral part of the addaptive strategy... i'm sure that it's not even very complicated to addapt a fuel map for that new setup for somebody who knows exactly what's about... not my case unfortunately but somebody like @Offtrack could give a better explanation i bet on that, i'd rather believe him than those who are selling expensive turbochargers for profit

Originally Posted by Tombie

And if you tee in on the inlet manifold instead of the turbo outlet pipe it gets even better!

Is that ok to do?

So currently my VNT is set with a silicone hose form the original location that went to the modulator unit pipe post turbo pre intercooler.

I have a barb on the inlet manifold with a hose running to my boost guage. I assume if I tee that and connect to the turbo it will get a lower boost pressure (due to boost drop over the piping and intercooler) and then the turbo would drive harder?

Sounds fun. Any ill effects long term?

No ill effects, and as you’ve deduced will be seeing the correct manifold pressure post IC drop.

Originally Posted by Tombie

No ill effects, and as you’ve deduced will be seeing the correct manifold pressure post IC drop.

Sweet, thanks. Another job for the future, but maybe after I've got a solution to my MAP/MAF issues as more boost will probably exacerbate it right now.

Enquired with Andrew Richmond of Les Richmond Automotive about his take on resolving the issue and received the following:

Might not be what you want to hear but these days we no longer use high flow AFM or boost boxes. All our VNT tunes have this all built in. So a simple tune can fix all these issues once and for all. You would need to put back on a factory AFM though.

According to their website < Performance Tunes > they use Alive Tuning products.

$720.00 to repurchase a new tune to replace my current one though < Performance Tune Disco 2 Td5 EU3 >
GBP 250.00 direct from Alive Tuning < Nanocom Ecu Remapping >
Then GBP 150.00 for updates if needed/wanted in the future < Td5 Remap Update >