05 TD4 Lumpy Running at 30mph in Third Gear.

Ever since I have had this vehicle(14 months with 115k miles on the clock),maintaining a constant speed in a low gear(for instance 30mph in 3rd gear) reminds me of a badly tuned carburettor --- lumpy verging on snatchy. Acceleration(hard or otherwise) throughout the gears is smooth---- I have never experienced this on any other diesel engine. The injector pump does leak slightly and I have replaced the fuel pressure regulator on the end of it(originally thinking that this was where the leak was coming from). I have had a couple of bouts(several months apart) of the engine running on when switched off. This has been like this, regardless of any replacement parts fitted(good quality lift pump and fuel pressure regulator) or modifications made (crankcase breather and blanked off egr valve which I wouldn't expect to make any difference anyway). Is this a tired injector pump or yet another Freelander idiosyncrasy?

I had a very similar problem with my Freelander TD4 2006. I related it to a misfire at around 1500 rpm which I would guess would equate to yours. Unfortunately I had to have an injector replaced, My garage had a bit of a problem spotting it as a leak down test was inconclusive, it only showed up using some electronic diagnostics. Also can I ask if your temp gauge is getting up to the middle of the range, because mine was not, and after doing the quick thermostat fix, it is running much smoother.

Thanks for the reply. Temperature gauge going to middle range. I had some diagnostics done on the fuel system a few months ago ,but no problems found.

This may sound odd but a drive shaft on the way out gave the feeling of a misfire on mine
No shaft all fixed

Not sure, but the running on when switched off I'd be cautious of. Could be oil leak into turbo. There's way to check posted somewhere on here, I think removing the charged air pipe and holding paper up to see if any oil comes through the turbo.

KZN130 said:

have had a couple of bouts(several months apart) of the engine running on when switched off. This has been like this, regardless of any replacement parts fitted(good quality lift pump and fuel pressure regulator) or modifications made (crankcase breather and blanked off egr valve which I wouldn't expect to make any difference anyway)

Click to expand...

Sounds like the turbo could be passing oil into the air, which would cause a misfire on light throttle, and running on after shutdown.

I'd be checking the intake pipes for oil contamination, as running on could lead to diesel runaway if it gets worse.

Just to humour me - try raising the revs in neutral to around 1500 rpm. If it misfires then, I think you have the same problem I had. I also had no faults showing on the diagnostics.