On the more random misfire some thing that has popped into my nogin was the old sticky valve syndrome you used to get on the old zetec engines, where although the valve goes up and down it doesn't rotate in the seat as normal due to the incorrect oil viscosity which caused them to stick open causing a misfire as it gets hot on one side, i cant remember if he fl2 is bucket and shim or hydralic tappets but a dodgy shim or bucket could be the cause of the issues

You may be on to something there. When I was putting the engine back together, I noticed one of the rockers on No3 cylinder (inlet I think it was) was loose, as in it wasn't being loaded by the hydraulic adjuster. I assumed it would improve as the hydraulic adjuster filled with oil after starting. I also noticed that the valves in this engine don't rotate as the engine runs. This to me is unusual, as I'm used to engines where the valves spin by action of the opening cycle. This design isn't like that, and the valve stems have U shape wear patterns on the top as a result.

Then the engine is started from cold, it definitely runs on 3 cylinders, and the exhaust makes a distinct chuff on the non running cylinder, so it could well be down to an exhaust valve not seating until it's warmed up. However this starting on 3 soon rectifies itself, and once it's running on 4 constantly, it's smooth as silk, unless I give it decent throttle above 2500 RPM.
 
The engine seems to be improving, although due to the diff failing, I've not driven him for a while.

The engine still starts from cold on 3 cylinders, but it's not so pronounced as it was.
The misfire under load is less noticeable when hot too.
I've noticed that the exhaust has a definite hiss to it, which is making me think the cat could be partially blocked. This would make sense, as the bits of broken piston must have gone somewhere. Maybe the misfire and slight delay in coming onto boost are related to a partially blocked cat.?
 
Sounds encouraging Nodge - and perhaps yes: definitely worth a look when you get a chance.

Unfortunately the design of the exhaust makes gutting the cat difficult, as there is a 90° bend before the cat, and a double kink after it. So unless I cut the pipe at the cat body, gutting it isn't going to be easy.

Hopefully he'll pass his MOT, so is driveable again, then maybe I'll remove the whole exhaust when the weather is better. I might be able to dislodge some of the aluminium that must have built up on the cat matrix.
Alternatively I can't see any option other than cut n gut it, or replace it completely.
 
Quite a lot of work if there is a chance the catalyst is okay. Any chance of getting a bore-scope down there to look at condition?
 
Quite a lot of work if there is a chance the catalyst is okay. Any chance of getting a bore-scope down there to look at condition?

It is, so yes I'll use my endoscope to check the cat.

I did do this while the head was off, but I couldn't get the endoscope around the 90° bend very far, as the O2 sensor was catching on the scope, preventing me from getting a good look at the whole matrix. I did see some evidence of metal in the cat, but it did mostly look clear.

There is a definite hissing when the engine is running though, so maybe the cat isn't as clear as I thought.

A new issue appeared this morning too, where after starting the engine after picking up some milk, the throttle pedal didn't respond until the 4th push, which was odd.

These FL2s are very complex, and seemingly quite fragile too.:(
 
I would not worry to much about the throttle pedal, I often come across it at work, jump in truck turn key it then thinks oh****you want me to actually start? and start it will but often there is no throttle respone for a second or two, I have always suspected this is linked to oil pressire, ie it is non existent to low so you cannot have any throttle.
 
I would not worry to much about the throttle pedal, I often come across it at work, jump in truck turn key it then thinks oh****you want me to actually start? and start it will but often there is no throttle respone for a second or two, I have always suspected this is linked to oil pressire, ie it is non existent to low so you cannot have any throttle.

Maybe. I've been doing lots of reading, and apparently a failing throttle position sensor can cause all sorts of silly faults, stalling, misfiring, hesitation and lack of power, which makes me wonder if the sensor is on the way out.
 
Maybe. I've been doing lots of reading, and apparently a failing throttle position sensor can cause all sorts of silly faults, stalling, misfiring, hesitation and lack of power, which makes me wonder if the sensor is on the way out.


Hey its only money:D
 
Maybe. I've been doing lots of reading, and apparently a failing throttle position sensor can cause all sorts of silly faults, stalling, misfiring, hesitation and lack of power, which makes me wonder if the sensor is on the way out.
Throttle body failure is common. It has two faults: broken teeth wheels gears and error in the track that generates the signal. Both are inside the body and can be verified by opening the tabs. The first does not leave fault code, the second I am not sure. Luck.
 
It is, but for the moment, I'm spending money on a new bathroom, so Buddy will get used as is for a bit.;)

Top tips,
Use only top quality silicone
Do not use cheap taps of any kind
Do not go for looks that will impede future repairs
Do not use a free standing bath as they are a pita
Do not use Italian anything, as its all word sizes/fittings etc

I of course ignored all of the above, and it has bitten me more than once over the following years!
 
Had a freelander 1 fail the mot on emissions a few years back, tried everything to resolve before eventually replacing the cat.

When I removed the cat, it was completely hollow and all the contents had blown out the tail pipe somewhere along the way.:)
 
The engine seems to be improving, although due to the diff failing, I've not driven him for a while.

The engine still starts from cold on 3 cylinders, but it's not so pronounced as it was.
The misfire under load is less noticeable when hot too.
I've noticed that the exhaust has a definite hiss to it, which is making me think the cat could be partially blocked. This would make sense, as the bits of broken piston must have gone somewhere. Maybe the misfire and slight delay in coming onto boost are related to a partially blocked cat.?

I'd definitely re look at valve clearances by the sound of it

re exhaust hiss go along underneath first and bash each silencer box you can get to, my money would be its more likely that a silencer box is failing apart internally which can cause them to block its rare from my experiences its rare for a cat to fail before a silencer , or there is a joint leaking somewhere
 
I'd definitely re look at valve clearances by the sound of it
The valve clearance is done with hydraulic lifters, so I suspect they are ok. The hiss heard when it's running on 3 could just be the non running cylinder being emptied by the piston on the exhaust stroke.
re exhaust hiss go along underneath first and bash each silencer box you can get to, my money would be its more likely that a silencer box is failing apart internally which can cause them to block its rare from my experiences its rare for a cat to fail before a silencer
I'm thinking more like the cat is partially blocked, due to all the bit of aluminium from the piston being stuck on matrix. In spring I'm going to remove the exhaust, so I can see if I can bang the cat out.

The vehicle only just passed the MOT smoke test, with a 149, where the fail is 150.
So it's not running perfectly.

I also noticed that it's got a regular misfire while driving on duel carriageway at 2000 RPM in top, but slow down to 65, and there's no misfire.

Very odd, but going by the high smoke test, I'm thinking maybe there's a split in a boost pipe, or the clogged exhaust is messing with the burn.
 

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