Discovery 1 MAF 14 CUX

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Could you pls clarify more on “make sure that all timing gear is in good nick” how do I check this pls ?

I checked the rota arm when the car is parked. It is facing the cylinder 1.
Make sure that the timing chain or belt isn't worn, stretched or has jumped a cog. The that tensioner is in good condition.
 
Well, you have the firing order that was easy as you had the drawing, so did you start plug lead 1 in the position as the drawing shown below next to the dizzy clip that at the bottom of the cap with a slight to the left, lead 8 is on the other side of the clip.
Hopefully you’re not going to need to strip the front of the to renew the timing chain and its tensioner.
No belt to worry about on the V8.

As to add a link to a similar discussion from a few years ago on this subject. https://www.landyzone.co.uk/land-rover/firing-order.128990/page-2
 
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Well, you have the firing order that was easy as you had the drawing, so did you start plug lead 1 in the position as the drawing shown below next to the dizzy clip that at the bottom of the cap with a slight to the left, lead 8 is on the other side of the clip.
Hopefully you’re not going to need to strip the front of the to renew the timing chain and its tensioner.
No belt to worry about on the V8.

As to add a link to a similar discussion from a few years ago on this subject. https://www.landyzone.co.uk/land-rover/firing-order.128990/page-2
Thanks. yes, 1 is next to the lead 8. And rota is pointing to the 1 lead when the car is stopped. Still I could pull out the plugged and check the TDC. so just to clarify, when the rota is pointed to the lead 1 and if I remove the cylinder 1 plug and put a screw driver in, I should feel the head on top position correct? And this is TDC?

Q, if the firering order is incorrect or dizzy is fixed 180 other way around, I believe the car will not even start or run right?

My issue is, car drives with a slight vibration, Mostly when the gear changes and when it is picking up. or when I take the foot out of the gas paddle for few seconds let the speed drop, then when you try to press the gas paddle for pickup you feel the vibration till it picks up the speed, once it on expected speed the vibration is less.

An update to the above,

I just pulled out the cylinder 1 plug and check, cylinder is on top position, I believe this should be a compression stroke, as the rota arm only pointing to the 1 lead mark. Attached few pics.
Thanks
Arshad
 
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The you slight vibration when rolling that you mentioned could be mechanical
Its not unknown for one or both of the prop shafts to have an issue, it could be as simple as the UJ s or prop shaft not being greased… if so get the grease gun out.
But then it could be a faulty UJ which is more involve in the checking them and replacing if required.

With your ignition system it seems now you have exhausted your options. ☹️
 
When I had this, or similar, it turned out to be the pinion drive nut hadn't been tightened correctly and had come loose. A garage had swopped the diff over a while before.
Not immediately obvious.
 
finally I have got the RoverGuage up and running… seems like the coolest temp sensor is not working properly. Attached are some pictures of the readings, kindly advise. And what more can be done to enhance the proformance…! 😂
 

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Nice!

The code for the coolant sensor is triggered by it being WAY out of range (or, usually, open circuit) - I assume the -16C reading was VERY wrong? You may have a wiring, or sensor issue there. The other one, where the fuel temp is 91C, but cooltant is 35C, seems off to??

There is a fuel/temp correction table, and the fuelling is increased as the coolant temp drops off.

I would VERY much investigate that first. You can check the terminals in the temp sensor plug for corrosion or damage. You can also get a couple of resistors that match certain temps according to the chart for the sensor, and see if the ECU sees it correctly.


THEN:
I hate to suggest fiddling with things for the sake of fiddling, but I suspect maybe you have a replacement MAF from an auto fitted - I'd suggest altering the CO trim down to maybe 1.2 to 1.3 as a starting point. It really should be set with the exhaust sniffer, but you also need to have the ignition system working perfectly and no other fuelling issues, so a guestimate should be OK. At least you know what it was set at before.

The CO trim ony really affects the fuelling at low load and RPM: from memory, by 3400 RPM it has no effect and has the most effect at idle (it tapers off). Same for load; not sure of the rate of decay.

Your vac advance not working will only really affect cruising economy, but checking the ignition timing with a timing light is a good idea. It probably can be advanced further than stock - I think mine says 6 BTDC standard, but I run 10 to 12, depending on the temperature and If I'm towing. (I have a high compression 3.9, and run 95 RON fuel).

There is some chance, that the poor running has just resulted in a buildup of somewhat raw fuel in the muffler, and once it was warmed and vapourised, a missfire etc ignited it.

Bonus: Prolly sounds pretty raspy now 🤪
 
Nice!

The code for the coolant sensor is triggered by it being WAY out of range (or, usually, open circuit) - I assume the -16C reading was VERY wrong? You may have a wiring, or sensor issue there. The other one, where the fuel temp is 91C, but cooltant is 35C, seems off to??

There is a fuel/temp correction table, and the fuelling is increased as the coolant temp drops off.

I would VERY much investigate that first. You can check the terminals in the temp sensor plug for corrosion or damage. You can also get a couple of resistors that match certain temps according to the chart for the sensor, and see if the ECU sees it correctly.


THEN:
I hate to suggest fiddling with things for the sake of fiddling, but I suspect maybe you have a replacement MAF from an auto fitted - I'd suggest altering the CO trim down to maybe 1.2 to 1.3 as a starting point. It really should be set with the exhaust sniffer, but you also need to have the ignition system working perfectly and no other fuelling issues, so a guestimate should be OK. At least you know what it was set at before.

The CO trim ony really affects the fuelling at low load and RPM: from memory, by 3400 RPM it has no effect and has the most effect at idle (it tapers off). Same for load; not sure of the rate of decay.

Your vac advance not working will only really affect cruising economy, but checking the ignition timing with a timing light is a good idea. It probably can be advanced further than stock - I think mine says 6 BTDC standard, but I run 10 to 12, depending on the temperature and If I'm towing. (I have a high compression 3.9, and run 95 RON fuel).

There is some chance, that the poor running has just resulted in a buildup of somewhat raw fuel in the muffler, and once it was warmed and vapourised, a missfire etc ignited it.

Bonus: Prolly sounds pretty raspy now 🤪
Yes. Coolent temp is extremely wrong. Out side temp here is not less than 30 Celsius. As I noticed from -16 it jumped to 35 Celsius. And it never moved from that point, even after a long drive.

Regarding the fuel temp sensor, it hiked above 95 Celsius it’s almost near to the boiling temperature, is this normal ?

So I have to start with the coolent temp sensor and fuel temp sensor. ?

Regarding the rover gauge, what does the fuel map indicator tells ? it changers on acceleration. Is it possible to tell if the injectors working working in the perfect order?
 
Coolant temp sensor is poked - fuel temp is probably normal? - it gets hot, being to close to the motor and heads.

Change the temp sensor for a good quality one.

If it's 30c outside, and the engine is actually at 90-something, then is REALLY overfuelling at -16C - it'd be like having an old choke hard on! Then even at 35C, that's pretty cold for an engine coolant temp. Plus with the co-trim set high - it's compounded.

In your 3rd pic attached, coolant says 35, fuel 91, but it's still requesting an idle speed of 1040 and is getting 995 RPM. If the coolant is in the 90's it should be idling at 600 in gear, 700 in Park/Neutral, + 50 for AC on.

Are you in Saudi or similar? Your tune says Map 3 - I believe that is Saudi spec 3.9, or UK/Europe 4.2L.
Fuel map shows RPM across the top, and load goes downwards, so wide open throttle, should get you down to (or near) the bottom row and it will move right as Revs increase.
 
Coolant temp sensor is poked - fuel temp is probably normal? - it gets hot, being to close to the motor and heads.

Change the temp sensor for a good quality one.

If it's 30c outside, and the engine is actually at 90-something, then is REALLY overfuelling at -16C - it'd be like having an old choke hard on! Then even at 35C, that's pretty cold for an engine coolant temp. Plus with the co-trim set high - it's compounded.

In your 3rd pic attached, coolant says 35, fuel 91, but it's still requesting an idle speed of 1040 and is getting 995 RPM. If the coolant is in the 90's it should be idling at 600 in gear, 700 in Park/Neutral, + 50 for AC on.

Are you in Saudi or similar? Your tune says Map 3 - I believe that is Saudi spec 3.9, or UK/Europe 4.2L.
Fuel map shows RPM across the top, and load goes downwards, so wide open throttle, should get you down to (or near) the bottom row and it will move right as Revs increase.
Yes. I live in Abu Dhabi, UAE, it is a GCC specs with Saudi tune.

It is getting difficult to find sensors for this model here locally. Any suggestions where to order?
 
Isn't by any chance the same type sensor fitted for ECT and FT too? if they are the same swap them and see the readings then cos that -16 reading is very suspect as i dont see how the ECU's ADC would calculate such negative value... i dont know how this 14cux fuel map's configuration is but usually for lower than 0 degrees it used to be the same fuelling strategy with a preset high IQ in many cases... did you try to see what ECT reading you get with unplugged sensor? if not this would be. good test
 
The Operation Pride tunes had different parameters for cold starts under -22C, so there must be some capacity for those measurements.

Weirdly, his tune is R3704, which I've never seen online anywhere, and Op Pride was R3652, plus there was a couple of other, like R3654. I've never seen any starting with R37xx
 
Isn't by any chance the same type sensor fitted for ECT and FT too? if they are the same swap them and see the readings then cos that -16 reading is very suspect as i dont see how the ECU's ADC would calculate such negative value... i dont know how this 14cux fuel map's configuration is but usually for lower than 0 degrees it used to be the same fuelling strategy with a preset high IQ in many cases... did you try to see what ECT reading you get with unplugged sensor? if not this would be. good test
Hey sorry for the -16 reading. I realized this was even the ignition is off. When the ignition is off and rover gauge is connected it take a default reading as -16 or -24. Swapping the ECT and FT is a very good point, yesss they are using same connector also I believe the sensor mechanism also it’s the same.
 
Hey sorry for the -16 reading. I realized this was even the ignition is off. When the ignition is off and rover gauge is connected it take a default reading as -16 or -24. Swapping the ECT and FT is a very good point, yesss they are using same connector also I believe the sensor mechanism also it’s the same.
You guys are amazing….

By swapping the connector I manage to figure out the mess done by the garage who replaced my engine. The RoverGauge did its Job… “we need to see what the ECU is reading”

The mess.
here we go….

Well, the FTS connector was connected to ECT So that’s why fuel temperature was showing above 90 Celsius.

And cylinder 1 injector connector was connected to the FTS, and FTS connector was in the cyl1 injector 🤦🏽‍♂️🤷🏽‍♂️

So the coolant temperature was not detected it was showing 35 Celsius flat.

Had to break my head to figure all these out… thank you for the rover gauge which helped to detect the correct connectors.

As I mentioned about the vibration, I believe this is due to cylinder 1 injector not firing as the wrong connector was connected. Didn’t get the time to try this with a proper test drive.

Attached few pictures after correct connection is done…



Thank you for your support….

Arshard
 

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Result!

Maybe don't use that garage again 🤣
Yes. Definitely. Is this reading acceptable? ECT is at max 93 and FTS is at 51. And target RPM at 894.
And should I look for another MAF to bring down the CO level from 1.91 ?

Also I noticed when the speed actual speed in the odometer shows 120kmph R-Gauge shows as 109 is this anything to with the performance or any calibration required… if it’s not effecting the performance I don’t bother on the speed showing. Attached pic.

Thanks.
Arshard
 

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The CO trim can be adjusted by removing the bung from the maf and carefully adjusting it.

Ive seen higher fuel temps than that on ine, but probably while running, parked - it probably runs cooler with more airflow in the engine bay.

Coolant seems correct - I think Standard thermostats are either 92C or 88C, depending on original specs.

I've not seen a target idle that high, when hot, but some of your pics show 650. You have unusual software version too.

Common versions use 600 RPM in gear for Autos / 700 in Park, +25 for each load - AC or heated windscreen.

That seems about right for speedo error. They generally show lower on the speedo than the true speed.

Drive it for a bit and see how it all goes 😎
 
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