4.4 TDV8 PCM updated
		
		
				
					
					
				
				
		
			
				
					Yesterday the PCM was updated, ostensibly to have the fix referred to in LTB00454 but hoping for particularly one other improvement, which appears to have been resolved although still early days yet.
LTB00454 refers to hesitation while using CC in the speed range 100-160 kph.  Mine had the pulsing at 110 kph on the drive home from collecting the vehicle late 2015 after which I tracked-down the known issue.  My vehicle was April 12 built which was well after the LTB was raised but obviously the PCM had already been programmed, wasn't updated at pre-delivery nor by the dealer when reselling the vehicle to me.  The instantaneous fuel consumption display would show consumption rising and falling by a significant degree in time with the pulsing which caused my body to rock back and forth.  On the drive home yesterday, which wasn't much of a test, the consumption display only slightly rose and fell at 100 kph but I've never felt the pulsing at 100 kph so no real confirmation yet.
The other issue which was my main concern was excessive torque converter slippage on take-off or after slowing turning into a street.   I had been told that this engine and gbox combination in the L405 doesn't suffer the same excessive TC slip.  The couple of standard spots since the update on both gentle and more normal acceleration have revealed far better behaviour, reminiscent of the operation of my previous 3.0 D4's rebuilt gbox with its updated torque converter.  One particular up-hill take-off from traffic lights next week will be a significant test.  The TCM s/w is at the latest level. 
The engine feels to breathe differently in undulating terrain where I now hear a very slight gurgle/burble on light throttle.  However I'm not accustomed to listening particularly attentively for engine noises which are barely discernible in the very insulated cabin anyway so nothing may have changed. The engine acoustic cover hasn't been fitted for a couple of years.
Anyway, the update looks promising.
				
			 
			
		 
			
				
			
				
			
			
				MY21.5 L405 D350 Vogue SE with 19s.  Produce LLAMS for LR/RR, Jeep GC/Dodge Ram
VK2HFG and APRS W1 digi, RTK base station using LoRa
			
			
		 
	
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