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Question Readings EGT; possible? (JTD)

Hi,

Also posed this question at the 939 chapter, but perhaps there is more knowledge out here.
I need to log readings of exhaust gas temperature from the sensor mounted just before the turbo (2.0 diesel);
Anyone who knows how to?

I have full licences of MES as well as AlfaOBD but neither of these seem to give acces.

(Issue is that lately I'm noticing a little bit less eagerness to clim through the upper half of the engine speed range, more precisely from 3,500 to 4,500 rpm. Looking at fuel quantity around approx. 3,700 rpm there is a little dip every time, hence the reason my technician advised to look at EGT values. Hope someone is able to help here.)

Many thanks in advance, Leo
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There is no option to read data from that sensor... Even Fiat Examiner does not have that option as far as I know.
I think it is "hidden" for a reason.
Only Alfas use this sensor (159, Giulietta), Bravo or Delta with "same engine" do not have this sensor at all.

But the problem you are noticing is related to EGT sensor.
I have seen a few cars that have limited power even in stock form above 3500rpm.
It seems like the sensor starts to degrade over time and give false readings to ECU which then reduces injection.
(but it could be also related to some other thing, like bad injectors causing high EGTs, bad remap...)

I have also seen one car that was completely undriveable, like it had 50HP.
No errors anywhere, after turning off the sensor, all power was regained.

So if your car is "stock" and goes into power limitation I would try to replace the sensor, or other option is to turn it off (not recommended).
If your car was remapped then it is probably just a remap fault.
This limiter is hidden quite well and most tuners who are not specialized for Alfas do not know where it is.
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you could hook up an egt gauge to the sensor and read it out directly.
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That is not the best idea

Usually EGT probes are K type thermocouples, but this one is not...
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then it won't work

can the signal be manipulated to read slightly lower? by adding a resistor or so? if that restores power, you know to change the sensor (or the map if it's been remapped)
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I think additional resistor would make it worse...
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depends how you do it... you could feed a certain voltage to the ecu so it thinks the temperature is still low enough.
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Question

Many thanks for both your valuable input, much appreciated this kind of quick support!

Pity that just this key sensor isn't released by aforesaid software tools, seems to me part of the basic data you want to read anytime. Well, fyi the car has been remapped twice, first one I had it reversed despite it went like a bullet (severe knocking in 4th at full throttle and increased consumption). Second one still in because I truly loved it the way the characteristic was improved without any downsides. Like it behaved as a petrol engine flying shifting up gears. Second remap was done by another professional company btw.

Only lately I got a Lambda error thrown up which I could firstly resolve by blowing out dry soot. But after about 10k it came back at which point I renewed the Lambda sensor. Strangely enough, the error code immediately returned and only after having it cleared several times in a row, it kept away for several thousand km's now. Readings are okay btw, as now.

The EGT sensor I had to renew previously at 80,000km (now 110k) due to going into limp mode right after almost every cold start. Replacing was the solution, but now again faulty would be unlikely to me. But still....perhaps?

Bad injectors could be, but there's nothing that indicates any such failure (correction values @2k rpm are between 0 and 1.5). No smoking or bad (cold) starts either.

MAF and BOOST readings are following eachother and rightly as desired at full throttle, however at cruising speeds in between, boost is ~0.2 bar too high compared to target. VNT lever is freely moving and vacuum is also checked. Even replacing a new control solenoid didn't make difference. I didn't open the housing yet as I don't believe the problem is that. Moreover because when it regenerates (between 300 - 500 km depending on driving profile), it there is no boost over atmospheric unless power is required.

Maybe I should consider investing in a scope as this is the one tool that's missing more and more diagnosing modern engine. For the moment I plan to go back to the tuning company and ask for their diagnose (as the nearby local Bosch Diesel Center isn't willing to look into non-standard vehicles).

I'll keep you posted once I found the root cause and solution to restore the performance.
Thanks again for any further input you may think of, cheers!
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who did those maps?
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