Td4 obd readings help please

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Blue407

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119
I'm trying to diagnose some starting and cut out problems on our 53 td4.

Using some software and obd hardware I have some values for an idling engine:

RPM: 776
Coolant temp: 68 deg
Intake manifold absolute pressure: 100kPa
Intake air Temp: 44 deg C
MAF Air flow rate: 11.89 g/s
Throttle pos: 0.0%

Forgot to mention I have a RoverRon synergy fitted along with a Pierburg MAF. I don't believe this has a intake temp sensor, so I presume the value is coming from the synergy.....

Does anyone else have some readings to compare?

To me the air intake temp is very high considering it's only 4 degrees outside!


The hardware is elm323 with some digimoto trial software. I really wanted to see some fuel pressure readings as I think the fault is fuel starvation related or the fuel pressure sensor.
Although the MAF and MAP are also possibilities.
 
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Hi, I use a permanently plugged in Scangauge2 and I can't get any fuel pressure reading.

RPM: 776 Spot on for idle.
Coolant temp: 68 deg a bit low - mine is normally 78
Intake manifold absolute pressure: 100kPa no comment - not sure about this one
Intake air Temp: 44 deg C this is the default minimum reading of minus 44 deg, there is probably a - in front of the 44 you didn't notice, possibly a faulty sensor or wire adrift
MAF Air flow rate: 11.89 g/s spot on for idle
Throttle pos: 0.0% correct for idle position

My Intake Air Temp at idle is usually 7 deg above the ambiant temp so I would have expected yours to have been reading 11 deg.

Hope that helps.

Singvogel. :cool:
 
Was doing some tests with Hippo ref a different problem but this link will show you live data readings from a 2001 TD4 if that helps

[ame="http://www.youtube.com/watch?v=mgIzMS-mFhs"]VIDEO0004.3gp - YouTube[/ame]
 
Hi, I use a permanently plugged in Scangauge2 and I can't get any fuel pressure reading.

RPM: 776 Spot on for idle.
Coolant temp: 68 deg a bit low - mine is normally 78
Intake manifold absolute pressure: 100kPa no comment - not sure about this one
Intake air Temp: 44 deg C this is the default minimum reading of minus 44 deg, there is probably a - in front of the 44 you didn't notice, possibly a faulty sensor or wire adrift
MAF Air flow rate: 11.89 g/s spot on for idle
Throttle pos: 0.0% correct for idle position

My Intake Air Temp at idle is usually 7 deg above the ambiant temp so I would have expected yours to have been reading 11 deg.

Hope that helps.

Singvogel. :cool:

S, 100kpa intake pressure is correct, it being absolute pressure ie, normal atmospheric pressure no boost.
 
Thanks guys!!

Is there a rpm I can take it to that you have readings for so I can compare them?

Shouldn't the synergy provide a temp reading instead of the default value?
Isn't that the point?
 
And it was probably low temp as I had only run it for a few mins to get some readings so it wasn't at normal operating temp.
 
Hmmmm

Are you taking the mick here, Mr Cox????

Being very genuine, I woulnt have had a scooby doo if those figures were right, wrong or whatever. Between you, hippo and a handful of others you could open up a dealership and actually fix these motors. I been busy reading the disco side for a while, since getting the V8, popped back here for a while now and then, still got my Td4!
 
I'm not sure exactly what set-up your engine will have as I think that 53 plated vehicles could be either before or after the point when they changed the air intake temp sensor from the MAF to the Turbo hose position.

Also I've noticed when I first start the engine I get the -44 reading for up to 10 minutes before I get the true readings. Same for mpg and some of the other readings.

Perhaps it would be a good idea to have the car fully warmed up and take the readings again.

I said my 'normal' temp was 78 deg. That's around town in Winter.

A long uphill run will make it go to 82 max.

In the Summer it's almost always 82.
 
Being very genuine, I woulnt have had a scooby doo if those figures were right, wrong or whatever. Between you, hippo and a handful of others you could open up a dealership and actually fix these motors. I been busy reading the disco side for a while, since getting the V8, popped back here for a while now and then, still got my Td4!

No probs mate, just thought that you maybe had me sussed as an 'anorak' type.

Part of the old-style training I suppose - take it to bits, clean it, look at it, then put it back together again, then do it in the dark - Ho Ho, not quite. :D

My LandRover travels started courtesy of HMG and I usually always had a team for back-up.

Nowadays when I'm back in Bosnia or Kosovo I realise that if it breaks there's only me to fix it. So I've genned up a lot since getting my first TD4 in 2002, and learnt some the hard way over some 200K+ milles.

Hope to catch up with some of you guys at the 1000+ HFH meet over Easter.

Singvogel. :cool:
 
I have a sensor inline on the intercooler hose from the manifold, is that a temp sensor? (I havent touched or cleaned that)

Here are some values from my testing this morning:-
Outside air temp around 3 deg C

At Idle
Calculated Load Value: 31.0%
Coolant Temperature: 66 Deg C
Intake Manifold Absolute Pressure: 101 kPa
Engine RPM: 779
Intake Air Temperature: 28.00 Deg C
MAF Air Flow Rate: 12.33 g/s
Absolute Throttle Position: 0.0%

At 1000 RPM
Calculated Load Value: 38.0%
Coolant Temperature: 66 Deg C
Intake Manifold Absolute Pressure: 101 kPa
Engine RPM: 1048
Intake Air Temperature: 29.00 Deg C
MAF Air Flow Rate: 16.14 g/s
Absolute Throttle Position: 7.8%

At 2000 RPM
Calculated Load Value: 45.5%
Coolant Temperature: 66 Deg C
Intake Manifold Absolute Pressure: 104 kPa
Engine RPM: 1964
Intake Air Temperature: 29.00 Deg C
MAF Air Flow Rate: 33.03 g/s
Absolute Throttle Position: 13.3%

At 3000 RPM
Calculated Load Value: 45.1%
Coolant Temperature: 66 Deg C
Intake Manifold Absolute Pressure: 114 kPa
Engine RPM: 2824
Intake Air Temperature: 30.00 Deg C
MAF Air Flow Rate: 51.34 g/s
Absolute Throttle Position: 16.1%

At 4000 RPM
Calculated Load Value: 25.1%
Coolant Temperature: 67 Deg C
Intake Manifold Absolute Pressure: 139 kPa
Engine RPM: 4020
Intake Air Temperature: 31.00 Deg C
MAF Air Flow Rate: 86.35 g/s
Absolute Throttle Position: 13.3%

Can anyone compare these to their values or comment at all on these?

To me, the Intake Air temp seems completely wrong. As mentioned previously I have a Synergy and Pierburg MAF fitted.

If we can get a set of correct value together for these it may help others diagnose problems on their cars if their readings are wildly different. Particularly with the MAF, MAP and air temp sensors :)
 
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Yes, the in-line sensor on the turbo hose is a temp sensor as far I understand it. A more realistic reading of intake temp is obtained there after having passed through the whole filter - turbo - intercooler system. Before I believe that the temp was taken at the MAF i.e. before the turbo.

Did you take those readings with the vehicle stationary? If you did then I feel that only the idling speed one would be meaningful.

I will try to take note of some readings over the next few days, on the move but no chance of a 4000 rpm one! :eek: Only problem with my Scanguage is that although I can get a load of different info from it, I can only have 4 of the scales displayed at any one time. Selecting a different group on the move is more than a little unsafe!!

I see that your coolant temp is too low. After a few miles on the road the temp should be at least 78 deg and perhaps higher depending if you've made the engine work a bit harder - e.g. pulling strongly up-hill. My max reading is usually 82/83 which I believe to be with the thermostat wide open and all fans running.

At idle or steady cruising speed my air-intake temp is always around 7 or 8 deg above ambiant. It can be a good bit more if the turbo is giving plenty boost when the engine is pulling hard.

Hope this helps for now.

Singvogel. :cool:
 
The readings look normal to me. Boost readings seems normal for a no load stationary engine. IAT sensor readings are correct as no flow through intercooler. Around about 13g/s from the Maf at idle (or around 500-510 mg/st. but some scope for variation according to slight idle speed differences.) Can't comment on the pierburg Maf above idle, although the whole point of the synergy/pierburg set up is to fudge the same (or higher) values as a Bosch.
 
I'm trying to diagnose some starting and cut out problems on our 53 td4.

Using some software and obd hardware I have some values for an idling engine:

RPM: 776
Coolant temp: 68 deg
Intake manifold absolute pressure: 100kPa
Intake air Temp: 44 deg C
MAF Air flow rate: 11.89 g/s
Throttle pos: 0.0%

Forgot to mention I have a RoverRon synergy fitted along with a Pierburg MAF. I don't believe this has a intake temp sensor, so I presume the value is coming from the synergy.....

Does anyone else have some readings to compare?

To me the air intake temp is very high considering it's only 4 degrees outside!


The hardware is elm323 with some digimoto trial software. I really wanted to see some fuel pressure readings as I think the fault is fuel starvation related or the fuel pressure sensor.
Although the MAF and MAP are also possibilities.


Sorry a Bit off topic but where is the ODBII socket on the freelander 1 TD4

Cheers!
 
Heres one I made earlier.......................

TD4Manualrealtimedataforposting.jpg


Data saved using Palmer PCMSCAN software with a MobyDic interface. It's my 2003 TD4 manual. Cursor position is at about 2,000 RPM
 
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