WLJayne

Well-Known Member
Hey guys,

My missus got a 10p off per litre at Snozbury's the other day so today I filled up the entire tank with super unleaded as I've read that it contains detergents and stuff that can be good for your engine once it a while. Is there really any benefit for a K series engine? Or would I have been better saving another fiver off of regular fool?

Will.
 
Not sure about the petrol but I filled up with BP's Ultimate diesel last week and I have noticed a positive difference. Seems smoother and more responsive on acceleration. Not Ferrari style power but definately better.

Only problem is that at £1.51 a ltr. I am not sure it will be a regular thing.

I have always used redex on every fill up but I thought I would try a can of BG244 along with the next tankful of Ultimate as I have read good things on here about it's cleaning properties.

Can't say that I have noticed if the redex has made any difference in the last few months, but I suppose you can't see what's going on inside!

Wondering if the Shell V-Power will be any better/worse/same?
 
I run my MG ZS180 (same KV6 as Freelander V6) on V Power as it runs a bit smother and feels a tiny bit more responsive. The Siemens ecu fitted to the KV6 will calibrate it's self over time to run on premium fuel. My V6 Freelander gets normal unleaded as the auto box masks any real improvement!! And at 20mpg would be ridiculous to run V Power anyway!!
 
I run my MG ZS180 (same KV6 as Freelander V6) on V Power as it runs a bit smother and feels a tiny bit more responsive. The Siemens ecu fitted to the KV6 will calibrate it's self over time to run on premium fuel. My V6 Freelander gets normal unleaded as the auto box masks any real improvement!! And at 20mpg would be ridiculous to run V Power anyway!!

+1 on the smoothness w/ the Siemans KV6 on high octane. I use Sunoco 94 here, and the fuel economy increases enough to pay the overage. Tested about 12 tanks full when I first purchased the Freelander, 87 vs. 91 vs. 94. 91 worked out the best for value, but the 94 ran better still.

Some of this may be due to the use of ethanol in lower octane fuels over here.
 
+1 on the smoothness w/ the Siemans KV6 on high octane. I use Sunoco 94 here, and the fuel economy increases enough to pay the overage. Tested about 12 tanks full when I first purchased the Freelander, 87 vs. 91 vs. 94. 91 worked out the best for value, but the 94 ran better still.

Some of this may be due to the use of ethanol in lower octane fuels over here.

You will get an improvement if you switch up from 87 once the ecu has calibrated it's self (around 500 miles) The ecu is factory mapped to 95 iirc (UK standard unleaded) relying on the knock sensors to retard the ignition timing for lower octane fuels. In the UK our premium grade is 98 - 99 octane so there is only a small improvement in smoothness and no fuel economy gain at all!!
 
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Interesting! Pure speculation, but I'm wondering if some of our KV6 carnage may be from the use of 87; knock sensors being a lagging control, some detonation would always be occuring (a killer for head gaskets and liner stress), and if the system can advance itself, it would have to be by constantly advancing timing until defeated by said knock sensors.

Have to dig into the lit some more...
 
Interesting! Pure speculation, but I'm wondering if some of our KV6 carnage may be from the use of 87; knock sensors being a lagging control, some detonation would always be occuring (a killer for head gaskets and liner stress), and if the system can advance itself, it would have to be by constantly advancing timing until defeated by said knock sensors.

Have to dig into the lit some more...

The initial ignition timing can be set using T4 for different markets so in the US the startup timing should be spot on unless someone forgot to set it for the correct market?? Once the engine is running I believe the knock sensors take over so keeping the ignition timing rite on detonation but it would have to detect the onset of detonation to retard the timing so I see your thinking ;) is the KV6 known for failure in the US? They fail here too. Normally HGF but it's often caused by the cooling system loosing coolant so dropping in level which then air locks and cooks the gaskets!!
 
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because the K-Series doesn't have a knock sensor it will not gain anything from using 98 ron fool!

save your money and stick to the 95 ron ;)



and this really will save it from detonating, really :eek:
What does a knock sensor do

The KV6 has 2 knock sensors!! One for each cylinder bank ;) It does run a bit smoother on Ron 98!! The K4 doesn't have knock sensors so will run on 95 or 98 but you will gain nothing from putting 98 in the tank!!
 
The KV6 has 2 knock sensors!! One for each cylinder bank ;) It does run a bit smoother on Ron 98!! The K4 doesn't have knock sensors so will run on 95 or 98 but you will gain nothing from putting 98 in the tank!!
the knock sensor prevents pre-detonation, if 98 ron is used in a 4 cylinder K-Series it could cause damage.
 
The initial ignition timing can be set using T4 for different markets so in the US the startup timing should be spot on unless someone forgot to set it for the correct market?? Once the engine is running I believe the knock sensors take over so keeping the ignition timing rite on detonation but it would have to detect the onset of detonation to retard the timing so I see your thinking ;) is the KV6 known for failure in the US? They fail here too. Normally HGF but it's often caused by the cooling system loosing coolant so dropping in level which then air locks and cooks the gaskets!!

Hi Nodge!
This is from the LRNA Freelander Technical Training book put out for dealers and techs; "During combustion knock, the frequency of (piezo-electric knock sensor) crystal oscillation increases, which alters the signal output to the ECM. The ECM compares the signal to known signal profiles in it's memory. If the onset of combustion knock is detected, the ECM retards the ignition timing for a number of cycles. When the combustion knock stops, the ignition timing is gradually advanced to the original setting."
And also; "If the knock sensor inputs indicate the onset of combustion knock, the ECM retards the the ignition timing for that particular cylinder by 3 degrees. If the combustion knock indication continues, the ECM further retards the ignition timing in decrements of 3 degrees, for a maximum of 15 degrees from where the onset of combustion knock was first sensed. When the combustion knock indication stops, the ECM restores the original ignition timing in increments of .75 degrees."

A few point related to this that I'm thinking about;

1. The ECM memory 'decides' if it's knock based on past history, either related to initial programming or previous operation.
- there's a lag as the ECM builds memory
- there's a lag as it responds
- the impetus is always to advance timing up to the knock point
2. US models are spec'ed OK by LR at 87 octane in the manual (approx. 91 UK), so;
- I'd assume that this is the initial ECM setting
- spark retards up to 15 degrees, but doesn't have an advance function
- fuel economy and running do actually improve- at least up to
91 US octane (94 UK), leading me to think that operation on 87
is a retarded condition of continually borderline knocking, with the ECM
constantly attempting to advance the timing. Pretty hot running...

...Big troubles with the KV6 here- yes overheating is causitive to complete failure, but the causes for overheating are generally coolant loss due to mechanical failure- liners and gaskets, as well as leaking heater cores brought about by over pressure situations caused by same. I'm thinking that detonation vibration and forces may be the underlying factor linking all of the above. Interesting to speculate on...

In researching other vehicles (to possibly replace the Hippo), I've been genuinely shocked to see how fragile modern engines are- mostly cooling and HGF! Maybe we're pushing them too hard...

(My other 'truck' is an '86 VW Golf NA diesel- no turbos for me:))

Scott
 
The US KV6 uses a different ecu and a different base calibration to cope with lower octane fuel but it still uses the knock sensors to keep the timing right on the point of maximum advance. The ecu is able to adapt the ignition and the fueling by + or - 10% iirc. It does take some time to adapt depending on driving conditions but is generally about 2 tanks of fuel!!
In the UK the Freelander is one of many MG Rover group cars to have the KV6 in a choice of 2 capacities, 2L 150bhp or 2.5 L with power ranging from 160 to 190 bhp. It is generally a reliable engine provided simple weekly checks on water are carried out but sadly this is often not done by owners and HGF is the result!!
 
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the knock sensor prevents pre-detonation, if 98 ron is used in a 4 cylinder K-Series it could cause damage.

Why? Higher octane should cause no damage except to your wallet!!
Lower octane would cause knock and engine damage ;)
 

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