TD5 compression figures

Hi all
I have a 2006 TD5 Defender. Had a few lumpy starting issues on a cold engine plus a slight loss in power. I did the usual ,check for oil on loom ,fuel reg, filter change, Injector seals and washers. Unplugged the MAF and no real change (may have even run a bit better with it unplugged).
I was not to worried about it until I bought a PSI Power box from Padockspares. yes I have heard a remap is the way to go but I needed a plug and play due to my isolated location, plus Padockspares and D44 sell them and I have heard these latest piggy back boxes by PSI are really good and don't mess to much with the ECU. When I plug the power box it starts first time and ticks over, if I rev it hard it stalls. Lots of clicking of relays and then wont fire up again for a minute or so or unless I unplug the box. After spending the money on the box I really want to remedy it!
I'm assuming its fuel related or electrical, on this its been to my local Land Rover dealer and since we have been round in circles.
My local dealer went ahead and did a compression test and says my compression is low. I'm baffled by compression figures given to be by my local dealer(Muscat, Oman). I know the TD5 only has 4 glow plugs so its a guess on the 5th, when I google compression results and look on forums I see 20, 25 etc.
My results on paper from the engineer were 200, 250,250,250. I don't know how to convert this or if it is really that bad. They are suggesting a new bottom end already and its a lot of money!
Any advice on these figures would be hugely appreciated. Information on Landys out here is hard to come by!

If it runs better with maf unplugged, that suggests the maf sensor is faulty, so I would swop for OEM maf, a faulty maf can affect starting and rough running,
I know my cylinder balances are more stable with a good maf sensor

By "bottom end" are they saying crank bearings? Not sure that will do anything to your compression figures!
If they mean re-bore etc then that would help, if thats the problem.
There is plenty you can do before having a complete rebuild though.
Make sure the MAP sensor is clean.
Check the crank sensor as well.
Try calling Turners and asking them about the compression figures.
My TD5 D2 came with a plug in box, its now in its own box in the corner of the garage! Not keen on plug ins!
If it really is poor compression, get the head checked first, could be the valves need regrinding.
Could also be that the environment in Muscat is aggressive, I tend to think of sand and dust, that could cause premature engine wear.
How many miles has she done?
Mark

A good engine should be around 400psi of compression I believe....

Stalling and lots of clicking sounds like an electrical issue to me though, have you checked the battery terminals are clamping tightly?

Thanks guys for getting back to me. I'm going to order a new MAF, then in a month take it to Dubai. Its getting expensive with all the trial and error!
The Dealer in Muscat does not explain very well, the figures 200,250,250,250 does not seem to mean anything when I search the internet and forums.

It's probably psi which at those figures is to low.
As said, 400 psi ish is what I would expect.

Its done200,000 km now Mark, thanks for all the advice. I'm going to check the MAP sensor this weekend and clean it, I found a good description on how to access that on the Australian Land Rover Forum. Crank sensor il google where to find that (I'm not much of a mechanic). Failing that I'm sending it to Dubai to some guys who know what there doing!
Cheers again.

Cool, good luck! Mileage not too high, but its the environment that can make a huge difference.
Discovery2.co.uk is a good site for step by step info on repairs.
Bet you get some great photo ops with all that epic scenery!
Mark

Bin that power box ASAP or sell it on ebay to some other candid guy who believes advertisings before making research(no offence) and never connect it again... those compressions are low, a good Td5 should have between 24 - 30 Bar(you convert it).... i can't tell you how to fix that

ok thanks Sierrafery. All noted. I googled pressure convertors and if there results are correct I would be running at 13 bar on one cylinder and less than 20 on the others. The landy still pulls through the gears ok, cruises nicely at 120kph. No smoke. would it even run if these figures were correct? My concern is the dealer I have to take it to I'm not convinced they know what they are doing, hence my next move is to take it to Dubai to known good landy place. I'm so hoping somehow the dealer got it wrong somehow and I don't need an engine rebuild as they suggest.
I just cleaned the MAP sensor, it was covered in black gunk.
MAF sensor plugged in and unplugged seems not to effect performace .
I just had injector washers and seals changed (by the Dealer) and cold starting is now worse...
Further googling I see that crank positioning sensor can cause similar issues, my issues I belive started around the time my transfer box failed and was changed, is it possible that the sensor could have been damaged when they did the Transfer box? Sorry for my ignorance, I read that it can gert damaged when changing the clutch and not being mechanically minded I'm not sure of the procedure.

See if the new dealer can do an electronic compression test. It is done using a current clamp around one of the battery leads. The current draw is then viewed via a laptop based oscilloscope.I've lost count of how many TD5's I've diagnosed this way,no need to even get your hands dirty ! The Picoscope I use can measure the actual pressure from one cylinder with a pressure transducer,(WPS500) and then has software to calcuate the actual pressure in the other cylinders - if you need it.The normal current clamp test is enough,poor compression on one or more cyls is enough reason to remove the head and inspect.
Just hope your problem is electrical rather than mechanical...

Nice one, are you speaking about something like this?

Never knew that could be done, pretty cool.

Yes, hopefully the attached picture will show a TD5 in VERY poor health. Its only a picture of the laptop screen,this is because the Picoscope software saves multiple pages and is difficult to post a single image... The Pico is a brilliant weapon,I've been using it this afternoon to view K bus activity on a 4.4 L322 with lighting faults,Testbook was unable to communicate with any of the modules on the K bus, but there was clearly activity happening. A leaky tailgate seal has caused havoc...

Throw it in the desert they are crap. You are messing with the ECU set up but remember your injectors are controlled by the ECU on a Td5 and it may interfere with those. You cannot tune an engine without proper rolling roads etc as how the hell can you set performance levels, also the air in the gulf is thinner and hotter so your engine will produce less power as your compression will be lower than the UK. It makes me laugh as people that sell these crap things never mention air density / humidity levels that anyone that actually knows how an engine really works would understand, Your better off putting a high flow performance air filter on and removing the EGR valve, run it at high revs and blow the crap out. Give the old girl more air as she is obviously struggling to breath

Did your dealer fit genuine land rover seals? Was it a genuine Land Rover dealership?? Britpart / aftermarket are crap and do not seal correctly. AVOID ALL AFTERMARKET PARTS......BUY CHEAP BUY TWICE. Also he may of not seated one correctly or cleaned the injector bore faces before assembly and have a bit of crap under a copper washer, its not uncommon. I have done lots of these after so called experts have screwed them up only to find a seal crushed or not properly prepared. You have to be 100 percent spot on clean and very very carefull on re assembly. Its a time consuming job.

Read my post on Td5 poor starting, I cured mine it was the fuel filter housing orange "bladder" valve. Not many people know its there (Including many Land Rover deales) and it is a part L.R do not sell, list or have even a part number for....its a complete housing I am afraid all for a bit of orange rubber! People try to say injector seals, fuel pump and all unsundry as they grasp at straws but thats not always the case. The orange valve is rubber and mine was very distorted /perished and allowed leak back probably due to ethanol as it is known to eat none nitrided rubber and when your defender was made fuel had no ethanol in it or any other enviromental crap!

Also wait for the fuel pump to stop ( 30 secs) after ignition on, press throttle 6 times and the pump will start again....bleeds air and helps poor starting,

Flossie said:

It's probably psi which at those figures is to low.
As said, 400 psi ish is what I would expect.

Click to expand...

Your not in the Gulf with thin air and temperatures of 40 deg ++ are you?? He is! Hence his engine will produce less power