TD5 Defender help - Low power

[nathanmac36]

Hi all,

2001 TD5 Defender with ~350K Kms was low on power and loosing coolant slowly so I had it looked at by a reputable LR mechanic. The mechanic advised the head gasket was no good and pressurising the cooling system causing the coolant loss.

I pulled the head off myself (which was pretty easy) and gave it to the mechanic to check and refurbish. Got the head back after a week and it had been pulled apart, skimmed, pressure tested, inlet valves replaced, exhaust studs replaced and injectors had new washers and O rings. They put my timing pin back in the cam to lock it in place.

At the same time of doing the head gasket I also replaced the following:

- Inlet manifold gasket
- Water Pump and cover (proflo brand)
- Injector loom
- Oil Cooler and filter gaskets
- Oil Cooler radiator core
- Oil Cooler reducer hose (small one at the back)
- Exhaust manifold gasket (had manifold checked by an exhaust shop for warping)
- All turbo gaskets
- fuel pressure regulator gaskets and O ring
- Fuel cooler coolant hose to radiator
- Oil Cooler coolant hose to radiator
- radiator pressure and flow tested
- intercooler cleaned out
- New oil, air and fuel filters (mahle)

I used Elring brand Head gasket of the same thickness as what came out and AMC head bolts. I've also installed a boost gauge and VDO coolant gauge to replace the standard one.

After refitting everything and firing the car back up it is no better on power (worse actually) but seems to idle and rev smoother. I followed the RAVE for setting TDC and locked timing before removal then setting the chain tension upon refitting.

Any ideas as to what could be causing it to be worse for power after all this? There has been considerable money invested into this issue that has yielded worse results than before.

I have thought that it could be the transfer case as it is a 61D 1.211 Disco TC but the power is definitely worse than before HG.


Thanks

[shack]

Of the jobs you have done on it, the performance related ones are:

Cam timing
Injector bump
Inlet and exhaust /turbo gaskets
Intercooler hose fitting

Those are the only ones that will effect the engine.

Did the engine get hot at all before the pull down?

[PhilipA]

I vote injector bump seeing all the work done.
Also wastegate jammed partly open, modulator wrongly plumbed/failing?

Regards PhilipA

[nathanmac36]

Of the jobs you have done on it, the performance related ones are:

Cam timing
Injector bump
Inlet and exhaust /turbo gaskets
Intercooler hose fitting

Those are the only ones that will effect the engine.

Did the engine get hot at all before the pull down?All inlet and exhaust/turbo gaskets seem to be okay. No exhaust leaks and inlet gasket was bolted back up before the head went on so it was lined up and torqued correctly.

Cam timing is possible but the crank was locked at TDC the entire time and the head was given back with the pin in place. The timing chain was tied to the sprocket and the links lined up with the mark when taking it apart and putting it back together. I turned the crank by hand all the way around until the links lined back up and there was no indication that anything was fouling

I've checked turbo hoses and there's no leaks. They're newish silicone hoses.

Injector bump I didn't check before putting it all back. I assumed it would have been set correctly by the mechanic. I'll have to look into it.

Cheers

[nathanmac36]

I vote injector bump seeing all the work done.
Also wastegate jammed partly open, modulator wrongly plumbed/failing?

Regards PhilipAI will have to look into injector bump as I didn't check it before firing it up.

Wastegate doesn't seem stuck. I can move it open and closed with some pliers and it springs back just fine.

No modulator in the defender. Wastegate is plumber straight from the hot side of the turbo.

Thanks

[shack]

It wouldn't make a lot of difference, but did the injectors go back in the same holes?

[Lionel]

Since it was down on power before all the work was done, have you checked the MAF sensor? My TD5 was down on power due to this cause - easily checked by unplugging it to see whether the default ECU setting improves the power delivery.

If it does, it's time to invest in a new MAF sensor.

Cheers,

Lionel

[Xtreme]

Since it was down on power before all the work was done, have you checked the MAF sensor? My TD5 was down on power due to this cause - easily checked by unplugging it to see whether the default ECU setting improves the power delivery.

If it does, it's time to invest in a new MAF sensor.

Cheers,

Lionel
I've got a spare MAF sensor which you are welcome to borrow and try.
It was just returned from a Td5 Disco owner who used it for about 5 weeks while he was waiting for delivery of a new one from UK. So it's had a recent test and I know it's OK.
PM me if interested, I'm in the Hornsby area.

[nathanmac36]

Since it was down on power before all the work was done, have you checked the MAF sensor? My TD5 was down on power due to this cause - easily checked by unplugging it to see whether the default ECU setting improves the power delivery.

If it does, it's time to invest in a new MAF sensor.

Cheers,

LionelHi Lionel,

The MAF was replaced around 18 months ago after the same mechanic advised that it was dud. The new MAF was VDO branded and it made absolutely no difference.

I've tried both original and new MAF before and after head gasket was done and neither has made a difference.

I have not checked with a scanner to see if the MAP sensor is faulty. I tried unplugging the MAP and there was a noticeable drop in performance from the already poor performance so assumed it was okay.
I might try another MAP sensor anyway.

Cheers

[nathanmac36]

I've got a spare MAF sensor which you are welcome to borrow and try.
It was just returned from a Td5 Disco owner who used it for about 5 weeks while he was waiting for delivery of a new one from UK. So it's had a recent test and I know it's OK.
PM me if interested, I'm in the Hornsby area.Thanks Xtreme but I've got 2 MAF sensors, one new and one original that was on the car when I bought it. Neither has made a difference.

I mentioned in another post that I'll try the MAP sensor as RAVE indicates the MAP has more to do with fuelling than MAF.

Cheers

[discopete]

Have you tried a different ECU?

[nathanmac36]

Have you tried a different ECU?No I haven't. It drove okay before HG was done so I didn't think it would be ECU related

[discopete]

No I haven't. It drove okay before HG was done so I didn't think it would be ECU related

Probably not. It's just a possibility I'd eliminate from the equation if it were me.

Cheers, Peter

[nathanmac36]

Probably not. It's just a possibility I'd eliminate from the equation if it were me.

Cheers, Peter

You may be on to something here.
I got a nanocom yesterday and connected it to see if any sensors were dud and the ambient pressure was showing 90kPa. The transfer case High/Low switch was also showing that it was in LOW range when its definitely in high. I know the throttle response normally changes when in low range so it may be that the power isn't as bad as I think. Just that the throttle response is in low range.

Another spanner in the works is this morning I have no crank at all and the ECU is saying its immobilised. Yesterday it running fine while I was looking through the nanocom readings and now ECU immobilised and no crank...

[shack]

You may be on to something here.
I got a nanocom yesterday and connected it to see if any sensors were dud and the ambient pressure was showing 90kPa. The transfer case High/Low switch was also showing that it was in LOW range when its definitely in high. I know the throttle response normally changes when in low range so it may be that the power isn't as bad as I think. Just that the throttle response is in low range.

Another spanner in the works is this morning I have no crank at all and the ECU is saying its immobilised. Yesterday it running fine while I was looking through the nanocom readings and now ECU immobilised and no crank...Ambient pressure as in map sensor? Yeah that's a bit low unless you are at about 1000m above MSL,

The transfer case switch thing is PROBABLY showing incorrectly, it has been for some years with the Nanocom...and it's hard to explain why, I think it's more of a diagnostic term than an indication of the range selected.
I'm not sure it's been rectified in the latest firmware.

Best way to check would be with Nanocom hooked up and going between high and low range and see if it changes, if it does I'd say it's all working ok.

As to the immobilizer...Dunno much about them, AS10 is known to be problematic, try locking and unlocking again see what happens.

Cheers
James

[nathanmac36]

Ambient pressure as in map sensor? Yeah that's a bit low unless you are at about 1000m above MSL,

The transfer case switch thing is PROBABLY showing incorrectly, it has been for some years with the Nanocom...and it's hard to explain why, I think it's more of a diagnostic term than an indication of the range selected.
I'm not sure it's been rectified in the latest firmware.

Best way to check would be with Nanocom hooked up and going between high and low range and see if it changes, if it does I'd say it's all working ok.

As to the immobilizer...Dunno much about them, AS10 is known to be problematic, try locking and unlocking again see what happens.

Cheers
James

Nanocom shows ambient pressure reading and manifold pressure as separate. The manifold pressure with ignition on but not running shows 102kpa which is correct for roughly 20m altitude.

I tried switching back and forth between high and low but there was no change to the nanocom reading saying it's in low range.

Problem with locking and unlocking is that I don't know if I have the original key and there is no FOB.
There was no central locking installed either so I'm not sure if the key would have even had a fob to mobilize the ECU.

[shack]

Nanocom shows ambient pressure reading and manifold pressure as separate. The manifold pressure with ignition on but not running shows 102kpa which is correct for roughly 20m altitude.

I tried switching back and forth between high and low but there was no change to the nanocom reading saying it's in low range.

Problem with locking and unlocking is that I don't know if I have the original key and there is no FOB.
There was no central locking installed either so I'm not sure if the key would have even had a fob to mobilize the ECU.Gotcha, you mean the sensor in the airbox, that should read roughly the same as the map sensor when the engine is off, if it doesn't you might have an issue.

On the key thing, I apologize,I was thinking more on the lines of the d2 which has a different setup.
You could unhook the battery and try again, but those AS10 ecu's have a bad rep for leaving people stranded.

[nathanmac36]

Gotcha, you mean the sensor in the airbox, that should read roughly the same as the map sensor when the engine is off, if it doesn't you might have an issue.

On the key thing, I apologize,I was thinking more on the lines of the d2 which has a different setup.
You could unhook the battery and try again, but those AS10 ecu's have a bad rep for leaving people stranded.

I did try disconnecting the battery to no avail. I find it strange that it was running fine up until I connected the nanocom. The nanocom did have some issues connecting and communicating with the ECU at times.
Once the ECU is immobilised, does it have to be re-mobilised to then accept a security code from the 10AS?

Thanks for the help.

[Lionel]

The ECU seems to be behaving a little strangely as shown by the Nanocom readings.

In view of your engine work, I would be carefully checking ALL earth connections - those to the engine and the ECU in particular.

Cheers,

Lionel

[nathanmac36]

Thanks everyone for the assistance!

After much research and talking to a few LR specialists I've figured out that the engine in my TD5 is not the original engine. From my VIN I should have a 10P EU2 TD5 but it is in-fact a 16P EU3 TD5.

Everything has been changed to the 16P/EU3 spec (TPS, AAP, head, injectors etc) EXCEPT the ECU! The ECU is still the earlier MSB type which "works" with the later engine but is not ideal.

The maps are still the EU2 maps and the ECU will not remember the last injector code so the engine is definitely not running as good as it should.

If anyone can point me in the direction of a NNN ECU for manual (500020 or 500250) that will hopefully sort out my issues!

Thanks again.

Nathan

[Xtreme]

It's been a while now since we heard anything about this low power issue.
Did you manage to get a replacement ECU and if so, did it rectify the low power problem?
Interested to hear what the outcome was.

[gruntfuttock]

Did you flush out any oil from the wiring harness that connect to the ECU? I had similar problems and it was oil in the harness that connects to the ECU, although the injector harness was new there was still oil in the wiring loom.

[Parker]

Did you flush out any oil from the wiring harness that connect to the ECU? I had similar problems and it was oil in the harness that connects to the ECU, although the injector harness was new there was still oil in the wiring loom.

How do you flush out oil from the wiring harness? Would love to know that.

[gruntfuttock]

Unplug the harness from the ECU and put some paper towel under it. Remove the injector harness from where it plugs into the loom, i think from memory its at the front of the head. Find a plastic coke bottle (i think 500ml but) check to see that this fits nice and snugly over the coupling point where the injector harness plugs into the loom, find an old tubeless tyre valve, drill hole in bottom of coke bottle and pull the valve into place. Place some ISO alcohol in the bottle (dont fill it) place a very very very slight amount of pressure just enough to say there is some pressure there but it should be negligible to the coke bottle and wait (you may want to lift and tie everything up some place. Any oil will drip out of the ecu end of the wiring harness. Repeat as needed till there is no oil. Hope this all makes sense? It took a few days the first time to “run clean”
I now change my injector harness every 100K before i get problems.

[nathanmac36]

It's been a while now since we heard anything about this low power issue.
Did you manage to get a replacement ECU and if so, did it rectify the low power problem?
Interested to hear what the outcome was.Hi Xtreme,

Yes I did get a NNN ECU and it did fix the power issues!
Overall the gearing was still a fair bit higher than stock so it was not fast off the line but it did cruise quite nice.