THANKS - MAF - MAP - Turbo Modulator FIXED

[Campdog]

Just joined but I have been searching this site for a fix for a sluggish 2004 D2 TD5. It was ok (we thought) unloaded, but was down to 40 kph uphill towing horse float.

I am posting this as I sometimes see threads that don't end with a solution, so here is mine that does end well.

This is what I found after reading here.

1. A surge after kickdown was the turbo modulator, replaced and surge fixed.
2. Borrowed Nanocom (as always recommended) to find MAF 50 at idle and topping out at 460 full boost. MAF replaced with genuine and numbers are in range
3. Turbo overboost error from actuator arm too short (12 threads) changed to 14, fixed.
4. MAP sensor was filthy. Cleaned and that alone made a difference.
5. Driver input error 1. which I learned could be from harness chaffing, not fixed but all the corrugated plastic near the engine crumbles when touched do that is the next job.

Wife came back from a short drive and said "It flies!". Will plug the nano in this afternoon and check the live stuff while she drives.

But if anyone has a tip for ... Nanocom Turbo Pressure live numbers rise then freeze back on 100 until the boost comes down again, goes well, no over boost error but cannot understand why this does not show live numbers. So I don't know what max boost is. Any assistance appreciated.

Thanks for the assistance you didn't know you gave already! Thanks for the valuable knowledge base when both local Agents could not look at it for a couple of months.

[shack]

But if anyone has a tip for ... Nanocom Turbo Pressure live numbers rise then freeze back on 100 until the boost comes down again, goes well, no over boost error but cannot understand why this does not show live numbers. So I don't know what max boost is. Any assistance appreciated.
.

Glad you're getting it sorted.

I'm not sure I understand the question, could you rephrase it or post a log with the issue in it?

[sierrafery]

The factory overboost limit is 1.42 bar, if it drops to 100 below that watch the MAF reading cos if it exceeds 680 the ECU cuts the fuelling as well and might not save a fault code

[Campdog]

Glad you're getting it sorted.

I'm not sure I understand the question, could you rephrase it or post a log with the issue in it?

Nano live display for turbo boost shows 100 at no boost (1 atm) on acceleration it climbs but then suddenly returns to 100 and that is frozen on on the screen. Meanwhile the car pulls hard anyway.

I suspect it has over-boosted, but no error code is registered. I see another poster has suggested it might be MAF numbers doing it.

I have the actuator arm at 14 threads (moved from 12) so I might have to back it off another one to keep it at or below max boost?

I haven't tried to record nanocom files yet.

[shack]

It's unlikely that an over boost has occurred but not been logged.

There could be several reasons for what you are seeing.

Does your car have a 3 wire sensor or 4 wire sensor on the airbox lid?

If it's 3 wire you have an EU2, if it's 4 wire you have an EU3.

They will behave differently to each other in the situation you are describing.

I'm guessing it's 4 wire- EU3, as the other would falter very badly when the readings went to zero.

It sounds like a faulty map sensor at this stage, but it would be good to get a log.

It could also have a "boost box" which is an aftermarket device that lies to the ECU to stop the vehicle from realising an over boost has occurred...