Well I've got the sport selector PCB sorted. However the box is still engaging 2nd, when is should select 4th, then slamming back to 4th, which triggers the F4 warning on the dash.

Without a diagnostic device that reads the TCM, I'm at a loss as to were to precede. :mad:
 
And on to the next issue.

I've been removing my bolt on additions, one of them being the Synergy power box.

Now the issue is there's absolutely no power at low revs. It will pick up speed slowly, until the engine gets to 2500, at which point it picks up some power.

Now I'm thinking MAF is responsible, and having the Synergy fitted was masking the low MAF signal. So do I find an alternative to the factory MAF (maybe just the insert?), or do I buy a Bosch MAF at great cost, or do I sell it as is.and knock a few £ off the price?

This car is really beginning to annoy me now. I'm sure it doesn't want me to sell it.

I've still got the gearbox issue to solve too.

Why oh why did LR have to fit a BMW engine in the FL. In my experience, only the BMW stuff goes wrong. :mad:
 
https://www.ebay.co.uk/itm/MASS-AIR...995315?hash=item3af9ad6bf3:g:gjQAAOSwVtZaJ0ss

I bought one of these some while ago and it has been fine - not saying they are all good- but for the price? Does the synergy fit in the fuel pressure sensor? You haven't got dreaded fuel pressure connectoritus have you !?
The Synergy fits both MAF and HPFR sensor. However the rail sensor is returning the correct pressure, so I'm guessing it's the MAF at fault. Low power below 2/2.5K is a typical symptom of a duff MAF. I've yet to unplug it for testing, because the gearbox is messing about so much.

I've got a couple of old MAFs, so will see if any of those make a difference.

I've ordered a second hand TCM for the gearbox, just so I can eliminate it as the cause of my issues.
 
Low power below 2/2.5K is a typical symptom of a duff MAF.

Well fitting another MAF has cured the sluggish revving and made it start from cold more quickly.

I also fitted a second hand TCM, but have yet to test it out. That's tomorrow evening's job. I'm not holding any hope of it curing the gearbox issue, but at least I can eliminate the TCM as the cause of the problems.
 
Quoting yourself now!! Is that like talking to yourself?

Spose it means you can agree.................
Glad one thing is sorted !
A reasonable auto box comes in at around £300 it seems, lot of work to sell it on. You may strike lucky with the TCM.
 
Quoting yourself now!! Is that like talking to yourself?
It's this car. It's making me go nuts.:eek:
Glad one thing is sorted !
One down, one to go, providing the MOT doesn't give me any surprises.
A reasonable auto box comes in at around £300 it seems, lot of work to sell it on
I don't believe that the gearbox is the problem. I think it's an electrical glitch, I just can't find it.
I'll definitely not be changing the gearbox, not on a car I'm selling. :confused:
 
You may strike lucky with the TCM
I've driven the car for a couple of miles, and so far, so good. The gearbox has behaved as it should. I know it's early days, but unfortunately the MOT is out, so can't drive it more until that is done. It's 10 miles to my MOT place, so I guess I'll see how it behaves on that drive. I'm keeping my fingers tightly crossed at this point!!
 
Sounds hopeful. Good conclusion would be to substitute old tcm into know good vehicle to see what happens. Maybe you just glad it's fixed!!
 
Sounds hopeful.
I'm keeping very cautious at the moment, simply because it has been so random a fault. After I changed the solenoids, it didn't do anything out of the ordinary for 3 months, which included some 30 mile trips (I only do local trips in it). It might do it on my way to work (9 miles) one morning, or not do it, or it could be fine going to work, and do it on the way home.

For instance, it did in less than 1/2 mile, after I'd sorted the Sport selector board, actually it was the second time it should have selected 4th. Because it's so random, I'm not at all surprised that it didn't do it on a 2 mile drive.
But I'm reluctant to sell it with a fault, so would rather give it a good shakedown before I let it go. Besides it'll be worth more if it ain't broken for the sale.

I also don't want it doing it on the MOT brake test, as the examiner takes it for a test drive. I guess time and distance will tell.
 
Just dropped the TD4 SE at the MOT garage. I'm hoping it passes, but I don't know this MOT examiner.

Oh and the gearbox decided to do its thing again, although after 10 miles this morning. :mad:
 
Well done on the MOT. The box issue does sound weird. Problems that pop up randomly are the worst to solve. I have one at work at the moment, nothing to do with cars, and its a right ****.
 
Well done on the MOT.
Thanks GG.:)
The box issue does sound weird.
It is, and very annoying.

Problems that pop up randomly are the worst to solve.
Indeed they are.
I'm thinking it's a broken wire to a solenoid valve, which is connecting most of the time. It's odd that after I replaced all the solenoids, the problem went away for about 3 months. Obviously I moved the gearbox harnesses about to do the solenoids, so I'm now thinking it's a broken wire somewhere.

Over the coming weeks, I'm going to power the solenoids in turn, right at the TCM connector, and wiggle the harness. I'm hoping this might identify any breaks, with an audible click from the box.

It's a shame, as the car is driving better than ever, although I'm now going to move it on, and return to a more basic, but hopefully more reliable FL1.
 
_____1st____2nd___3rd___4th___5th
A_____X_____O______X_____X____O
B_____O_____O_____O_____X_____X
C_____O_____X______X_____O____O

X = solenoid off
O = solenoid on
ABC = shift solenoids

Just a thought. If solenoid B was to fail, while the box is in or selecting 4th. Then wouldn't the box would actually go into 1st?
Although I've changed all the solenoids, and the problem went away for 3 months. I'm still thinking wiring, although all the solenoids test ok at the TCM. :confused:
Your thoughts!@Hippo @Diesel Do
 
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Just a thought. If solenoid B was to fail, while the box is in or selecting 4th. Then wouldn't the box would actually go into 1st?
Although I've changed all the solenoids, and the problem went away for 3 months. I'm still thinking wiring, although all the solenoids test ok at the TCM. :confused:
Your thoughts!@Hippo @Diesel Do
Yes it should in theory, as it will only go to 4th IF the correct solenoids activate. So by return logic it would drop to 1st if B were to switch oft, as it's then changing the flow of auto fluid.

I will read through this whole fred later or tomorrow from the start to recap whats been said and done so far.

But while I'm ere, am I right in saying the problem occurs when in auto Drive (when cruising at constant speed on level ground in 4th) but doesn't happen when manually selecting gears using Command Shift and leaving it in Command Shift when cruising? If so that would suggest failure caused by it detecting it needs to change gear, as opposed to something like solenoid B dropping out. If it does happen when using Command Shift then that theory is dead, but it means a random drop out of solenoid B could still be the cause (or result affect of something causing that).
 
Yes it should in theory, as it will only go to 4th IF the correct solenoids activate. So by return logic it would drop to 1st if B were to switch oft, as it's then changing the flow of auto fluid.
That's the thought train I was following. However I've changed all the solenoids, which fixed the problem for 3 months.
am I right in saying the problem occurs when in auto Drive (when cruising at constant speed on level ground in 4th) but doesn't happen when manually selecting gears using Command Shift and leaving it in Command Shift when cruising?
It's tricky to answer that, as the fault is so completely random.

However it seams to manifest itself when in D, and the box is going up to 4th, or dropping down to 4th.
If so that would suggest failure caused by it detecting it needs to change gear, as opposed to something like solenoid B dropping out.
I thought it was a TCM issue, once it did it 3 months after I'd changed the solenoids.
If it does happen when using Command Shift then that theory is dead, but it means a random drop out of solenoid B could still be the cause (or result affect of something causing that).
However it has done it in Command Shift to, although only once I think.

I have found that using CS does seem to reduce its occurrence, although maybe not, as it's so random.

I do know that when it's done it's thing and dropped to 1st, using CS doesn't help the box change up to 2nd, even though the LCD shows 2, the box remains in 1st. If I keep driving as a steady speed in 1st, the box will all of a sudden change up. If it does this up change in CS 2nd, then the up change is smooth, providing the revs are kept under control.

However if I'm being cross with it because it's stuck in 1st while D is selected and I'm revving the nuts off the engine. When the box changes up, it does so without any torque reduction, and thumps in really hard. This causes the F4 to flash, and the box locks in 4th, after which it'll drive all day and cause no more issues. Now my thinking says, if No4 solenoid was faulty, it couldn't stick in 4th and stay there.

This is making me wonder if there's a hardware problem with the gearbox, and not an electric fault at all.
 
So the auto box has been working fine for the last 100 miles or so, until I put my foot down this morning. It went through 1st to 3rd just fine, only for the engine to race as it went into 4th. :mad:

It seems odd that driving it normally keeps it working correctly, but give it a bit of stick, and the box plays up. I'm still trying to come up with answers, but maybe the harness has a damaged wire, which is breaking a circuit when the engine rocks about under heavy loads?:confused:
 
Fluid pressure related?? I'm sure that the fluid is spot in, but have you double checked the fluid level? I was surprised having done my TD4 to the procedure, only to find a few months later when I checked it. it was overfull by about 0.25 L.

If driving it harder is making it fail, worth a thought??
 
Fluid pressure related?? I'm sure that the fluid is spot in, but have you double checked the fluid level? I was surprised having done my TD4 to the procedure, only to find a few months later when I checked it. it was overfull by about 0.25 L.

If driving it harder is making it fail, worth a thought??

I'm pretty sure the fluid level is bob on. I'll check it again though.

It seems it's heat or power related. It's been fine when driving it carefully, but the moment I put my foot down, it started to misbehave.

It also seems to do it more after it's been left idling for a period of time when hot.:confused:
 

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