Disco 2 Loss of power STILL NOT SORTED, BUT...

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Billy110

Billy110

Member
Posts
81
Location
North Notts
Hi All,

The frustration continues...

Loss of power (engine revving but little drive) still present.

MAF sensor proved to be defective - replaced.
MAP sensor - cleaned.
Air box temp sensor - cleaned.

Engine still sounded lumpy, found a tiny bit of oil in the red plug, but not the ECU.

Injector harness - replaced.

Engine sounded lovely again and had a higher range of RPM.

Took it out for a test drive, same symptoms...

I’m looking to by a Nanocom or HawkEye on Tuesday, in the meantime, is there anything I can be looking at?

Should I be cleaning the plug every day, would you expect it to need repeatedly cleaning in the short term?

I’m not convinced I don’t have a gearbox fault.

How reliable are the Auto TD5 boxes? I would expect them to be bomb proof...?
 
Billy110 said:
Hi All,

The frustration continues...

Loss of power (engine revving but little drive) still present.

MAF sensor proved to be defective - replaced.
MAP sensor - cleaned.
Air box temp sensor - cleaned.

Engine still sounded lumpy, found a tiny bit of oil in the red plug, but not the ECU.

Injector harness - replaced.

Engine sounded lovely again and had a higher range of RPM.

Took it out for a test drive, same symptoms...

I’m looking to by a Nanocom or HawkEye on Tuesday, in the meantime, is there anything I can be looking at?

Should I be cleaning the plug every day, would you expect it to need repeatedly cleaning in the short term?

I’m not convinced I don’t have a gearbox fault.

How reliable are the Auto TD5 boxes? I would expect them to be bomb proof...?
Click to expand...

Just a thought have you looked at the egr being at fault or is it blocked off.

Also I have a D2 td5 nanocom I might consider selling ;)
 
Ok, progress I hope...

Hawkeye arrived today.

Live faults displayed are:

3007 Ambient pressure low

3039 Ambient pressure

When I looked at the live data, the ambient pressure didn’t move from 100.0kPa.

Is this the MAP sensor or something else?

Sierrafery...?
 
Billy110 said:
Ok, progress I hope...

Hawkeye arrived today.

Live faults displayed are:

3007 Ambient pressure low

3039 Ambient pressure

When I looked at the live data, the ambient pressure didn’t move from 100.0kPa.

Is this the MAP sensor or something else?

Sierrafery...?
Click to expand...

If you want to alert a member you have to @sierrafery
 
Hi All,

Still taking any advice you can give...!

I now have Hawkeye, and cleared faults that were present, so no faults are showing now.

I’m now thinking I might need to start replacing sensors with Genuine LR parts, but would like to know which sensors are critical to be Genuine.

I haven’t touched the Crank sensor, would I expect this to give me loss of power and not show up on Hawkeye?

At a bit of a loss, and don’t like just swapping parts blind and for the sake of it.

Work so far:

Replaced MAF sensor (Siemens VDO but not Genuine LR) - Voltage changes with demand and on Hawkeye
Replaced fuel regulator sensor (Bearmach)
Cleaned ambient pressure sensor - pressure changes on Hawkeye
Cleaned MAP sensor - pressure changes on Hawkeye
Freed off waste gate mechanism

Not sure where else to go now without ‘gambling or guessing’ my money away.

Any ideas guys?
 
Copper washers on injectors, I had similar symptoms on my old one after doing all that you have done it turn out to be them.
Not sure what this would show up as on nanocom but just an idea mate
 
MikeDISCO said:
Copper washers on injectors, I had similar symptoms on my old one after doing all that you have done it turn out to be them.
Not sure what this would show up as on nanocom but just an idea mate
Click to expand...

Thanks Mike.

Big job? Any pitfalls to avoid?

Did you have any visible symptoms, visible fuel leak etc?
 
Billy110 said:
3039 Ambient pressure
When I looked at the live data, the ambient pressure didn’t move from 100.0kPa.
Click to expand...
I missed that post then, it's about the AAP sensor which is in the airbox, when this one fails the ECU goes to that 100KPa default but the boost is limited to 1bar, no wastegate modulation and the engine is powerless, for Eu2 engines it's frigging expensive but you can buy a (Eu3) 4 pin connector from a scrapyard, wire the 3 needed pins to the loom and connect a Eu3 sensor which is cheaper or find a verified working AAP sensor, a good one at idle will read very close to the real ambient pressure compared to a barometer or the MAP reading and the it's reading will drop few units under load
 
Last edited:
sierrafery said:
I missed that post then, it's about the AAP sensor which is in the airbox, when this one fails the ECU goes to that 100KPa default but the boost is limited to 1bar, no wastegate modulation and the engine is powerless, for Eu2 engines it's frigging expensive but you can buy a (Eu3) 4 pin connector from a scrapyard, wire the 3 needed pins to the loom and connect a Eu3 sensor which is cheaper or find a verified working AAP sensor, a good one at idle will read very close to the real ambient pressure compared to a barometer or the MAP reading and the it's reading will drop few units under load
Click to expand...

Thanks @sierrafery

When this fault was present, embarrassingly, I hadn’t reconnected the sensor after cleaning it.

Reconnected, it reads and changes with pedal demand.

No faults showing on Hawkeye.
 
Possible progress in a strange kind of way.

I think I had/have 2 faults, and confused the diagnosis.

I definitely had engine problems, rough idling etc, and proved the MAF to be defective which I changed. I still had loss of power, or so I thought...

Being happy I couldn’t find any more sensor issues, Hawkeye clear, I took it up the A1 for a test run.

When I floor it/high demand/load, the revs drop off, but only after it SHOULD have changed gear. I think the auto box is slipping under high load.

So, I serviced the box last night (will change the oil again in 100 miles or so). Took it for another test drive. Beautiful gear changes from the get go, but still slipping (then dropping the revs off) when I floor it.

When I change the oil again, I’m going to try some Lucas Transmission Fix to see if it clears, if not, I’ll be on the hunt for a new gearbox. I’m hoping it isn’t terminal, the oil wasn’t ‘too’ dirty, not black anyhow, and the magnet was clean. Fingers crossed!

When I did the box last night, I noticed my front brake hose was split and leaking, so swapped that this evening. She is certainly keeping me busy lately!

Thank you for everyone’s help and suggestions, but I’ll be back asking more questions if I’m swapping the box out!
 
> When I floor it/high demand/load, the revs drop off, but only after it SHOULD have changed gear. I think the auto box is slipping under high load.

Sounds bit like how overboosting "felt" when I had it. Caused by defective boost valve, ECU cuts the power when the valve fails to modulate boost pressure (to avoid engine damage).

Not sure if this would show up on Hawkeye
 
joojar said:
> When I floor it/high demand/load, the revs drop off, but only after it SHOULD have changed gear. I think the auto box is slipping under high load.

Sounds bit like how overboosting "felt" when I had it. Caused by defective boost valve, ECU cuts the power when the valve fails to modulate boost pressure (to avoid engine damage).

Not sure if this would show up on Hawkeye
Click to expand...

Thanks Joojar.

I forgot to post that I have swapped this, and the injector harness too. Although I wouldn’t rule out new items entirely.
 
Are you sure it's not overboosting? .... as for the gearbox, run a stall test on it

Stall test.jpg
 
Overboost could also be caused by stuck-closed wastegate on turbo. Plenty of threads on here involving mole grips and liberal quantities of WD40
 
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