Defender TD5 Wastegate adjustment

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Well the plot thickens as Dynachip has just been to do a proper remap and turns out the engine wiring harness is off a 15p TD5 engine. When I bought the vehicle years ago I noticed the AAP plug was off (this thread: https://www.landyzone.co.uk/land-rover/missing-plugs-etc.234344/) but didn't get much of a response so got the right sensor for the plug and installed it in a new hole in the air box.

My MAP sensor is maxing out at 172 and he said it should be getting to 230 easily with the map hes done. He suggested getting a new (10p) loom.
 
The problem is that you never said what year/type of the engine you have also this low MAP reading with high air flow was already explained in my first reply but then the topic went in other direction... if it's a 15P loom with 4 pin AAP sensor it should be OK for 10P engine cos the ECU gets the AAP reading and simply neglects the AAT input, watch the AAP under load, it should not drop more than 3-4 units or if it's constantly 100 it means the ECU is on default for AAP and then the boost is reduced by the ECM.... as long as you get close to 600 air flow(sucction) it means that the boost created by that is lost somewhere not a management issue
 
bankz5152 said:
Depends on the length of the probe really.
Click to expand...
about an inch long give or take a few mm
in this case most of the EGT gasses from pistons 2 to 5 would of escaped into the turbo you will find there is a couple hundred + degree difference measuring the exhaust flow
 
Too bad they didnt make long probes as to cover all the 5 cylinders inserted through the blank plate ;), though the difference in reality for pre-turbo measurement is not big at all from the plate to central fitment cos if let's say cyl 5 goes wrong all the others will compensate for it and the EGT will rise on nr 1 then, i compared mine(probe in the plate) with a friend's with probe right before the turbo an didnt see any noticeable difference, after many tests i made i decided that i'll relocate my probe post turbo and take into account the temperature drop cos this way the probe will not burn out in 3 years like the others
 
sierrafery said:
Too bad they didnt make long probes as to cover all the 5 cylinders inserted through the blank plate ;), though the difference in reality for pre-turbo measurement is not big at all from the plate to central fitment cos if let's say cyl 5 goes wrong all the others will compensate for it and the EGT will rise on nr 1 then, i compared mine(probe in the plate) with a friend's with probe right before the turbo an didnt see any noticeable difference, after many tests i made i decided that i'll relocate my probe post turbo and take into account the temperature drop cos this way the probe will not burn out in 3 years like the others
Click to expand...

ask your self why they don't make probes long enough for this reason ..the EGT gauge is to monitor full out put of the engine not just in a small area

you can never compare 2 engines the same as there is to many factors involved
glad you have also took into consideration the temp drop when you have relocated the sensor all because the sensor will burn out 3 years ..... this is a bit like buying light bulbs for your home but keep them stored away in a box because you don't want to burn them to burn out

I actually work with ADD blue systems that run need to run EGT sensors ....if these sensors do not work correctly these can cause all kinds of issues as its in printed into the ECU .. we have found periodic cleaning of these sensors last longer .. by removing deposits that can create heat spots . and we also monitor values of the sensor with a multi meter ....and a record is kept for future reference basically a blue print ..... we have had some cheap EGT sensors burn out less than 16 months but buy cheap buy twice

however invert this senerio.....if cyl 1 and 2 fail and 3 4 5 are compensating your early warning device might be to late . unless you think heat soak will save you..
sensor location is crucial you have to take into consideration heat soak and pulses within the exhaust manifold ..

for example the engine cooling gauge is located at the front of the engine ..if you where to install an another cooling gauge at the rear of the engine you will notice the rear of the engine runs hotter than the front ..its the nature of the system

as for the EGR port is only a scavenging location on this desired engine that met emission specs back in the day ..not exacxtly a true reading of EGTs is it
 
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sierrafery said:
The problem is that you never said what year/type of the engine you have also this low MAP reading with high air flow was already explained in my first reply but then the topic went in other direction... if it's a 15P loom with 4 pin AAP sensor it should be OK for 10P engine cos the ECU gets the AAP reading and simply neglects the AAT input, watch the AAP under load, it should not drop more than 3-4 units or if it's constantly 100 it means the ECU is on default for AAP and then the boost is reduced by the ECM.... as long as you get close to 600 air flow(sucction) it means that the boost created by that is lost somewhere not a management issue
Click to expand...

Thanks yes I should have said but didn't think it relevant until it was pointed out the wrong loom is in there! We tested the loom last night and there doesn't appear to be anything wrong with it but without a boost pressure gauge on the inlet side we can't tell if it's the sensor or a restriction. The fact that two ecus and two map sensors read the same suggests there's a restriction or leak somewhere. I'll be putting a boost gauge on the inlet but later today I'll check all the hoses again I'm hoping it's a loose hose or something. Air flow gets up to around 650 and boost 22/23psi on turbo side and the inlet is relatively clean just a thin film on the inside, and the intercooler is virtually new. The AAP reading is 100 with the engine off and goes down to about 89/90 when running - not sure how to check if that's correct ?
 
you need to fix the issue of the air intake sucking in this should not be sucking in regardless if all sensors are working nor should it suck in with the engine pulling more HP ... if this is sucking in with bonnet off.... whats it going to be like when bonnet is on combined with under bonnet temps .... engine loads also create higher engine bay temps thus make plastics and bends more softer
I would also check all connections on sensors specially the female pins . these can open up due to heat related issues specially on the MAP sensor as it reads 2 things pressure and temp

a mechanical gauge will give you a true reading from the manifold ..you will need to take into consideration relative pressure when reading eltronically . or maybe the MAP sensor is out of calibration or wrong bar of sensor is used
 
I think it's just old and weak I don't think it's anything to worry about particularly. Unhooking the snorkel has helped for now but I think there is a leak somewhere. The egr blanking plate had some black soot around it with no noticeable gasket same with the inlet side - this was done before I had the vehicle. Thing is on the turbo side all looks good, but the MAP is reading only 170-179 on the other side. Not much I can do until I have a boost gauge fitted to the inlet to see what it's actually getting
 
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tom1979 said:
Air flow gets up to around 650 and boost 22/23psi on turbo side and the inlet is relatively clean just a thin film on the inside, and the intercooler is virtually new. The AAP reading is 100 with the engine off and goes down to about 89/90 when running - not sure how to check if that's correct ?
Click to expand...
such air flow means that the engine management is OK as it's able to get to that sucction, in this case if the MAP sensor is 100% good it's a leak somewhere or the turbo is fubar on the compressor side... are you sure that the wastegate isnt stuck opened?

i doubt that the AAP is the problem but to check it compare it's reading at idle with the real pressure shown by a barometer cinverted in KPa cos it should be the same
 
sierrafery said:
such air flow means that the engine management is OK as it's able to get to that sucction, in this case if the MAP sensor is 100% good it's a leak somewhere or the turbo is fubar on the compressor side... are you sure that the wastegate isnt stuck opened?

i doubt that the AAP is the problem but to check it compare it's reading at idle with the real pressure shown by a barometer cinverted in KPa cos it should be the same
Click to expand...

You don't think it's related to the newer (15p) loom? Boost pressure on turbo side was 23psi
 
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It's reading 89/90 which I thinks probably a bit low if anything - 100ish is normal ? 1 kPa is 0.01 bar. My work camera has a barometer on it reading 1040hPa (not sure what hPa is but assume it's the same as millibars)
 
tom1979 said:
It's reading 89/90 which I thinks probably a bit low if anything - 100ish is normal ?
Click to expand...
Normal is to be very close to reality with ignition on and to drop up to 4 units at high revs... 100 is the default value though i've already explained that if it was a fuelling reduction caused by bad AAP signal you couldn't have rev'd it up so hard to get 650 sucction cos it would have been gutlless... read everything i say dont be focused only on the AAP thing

1000hPa = 100kPa
 
So it should be reading around 100 as the pressure here is 1040. I'll whip the turbo off and get it checked. Maybe the wastegate valve itself is stuck or disconnected somehow
 
Yes, take a reading with the sensor removed from airbox cos if it's some restriction in the intake the reading drops even at idle but better concentrate on the compressor side cos if the turbo spins so fast to suck 650Kg/hr air it should deliver 210KPa MAP reading(1.1 Bar boost) with wastegate factory setup...off course if all the sensor's inputs are accurate
 
The turbo is off and the wastegate valve appears to be working but I'm going to take it to a place at Northampton for it to be checked. I'm hoping it's the turbo that's knackered I can't see where else it's being lost!
 
How did you measure that 23 psi there?...do you mean that the turbo delivers 23 psi boost and this doesnt reach the inlet? cos in this case the turbo is OK and it's a leak between it and the inlet somewhere
 
We put a t in and a boost gauge and it read 23psi as previously said but the map sensor read only 173kpa ish max. This was tested with different ecu's and different map sensors and different software. We checked for leaks, even bypassed the intercooler and the reading is the same. Dynachip said get a new (proper 10p) loom but from what everyone said it's not the loom as the difference is only the AAT reading. My boost gauges haven't come yet so can't accurately measure the inlet side
 
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