Instructions to change fuel maps on 14CUX Griffith, Chimaera
Discussion
Steve- I dont yet have a good 3.9 non cat map- Im running the stock Range Rover map at the moment but it runs lean progressively above 3500 rpm however so its not ideal, I just need to get around to tweaking it. Id be quite interested just to try your own modified map and see how it runs as the engine spec's are not that far apart.
Edited by blitzracing on Saturday 9th August 19:56
The MIL lamp in TVRs is a long standing problem it seems:
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
It appears some TVRs had the MIL function enabled some didn't, and judging by the problems it was (is) causing, especially with intermittent operation, it's no wonder the code provided for a MIL disabled option.
But the confusion continues, is the dash lamp controlled by an ECU transistor switched earth via pin 10 or, as Steve has determined, by the ECU applying 12Vdc to pin 10? Some info on this here:
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
So I'm going to go with a thorough check of the lamp wiring and:
NEW_STYLE_MIL_CODE = 1
for the next build and see what happens.
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
It appears some TVRs had the MIL function enabled some didn't, and judging by the problems it was (is) causing, especially with intermittent operation, it's no wonder the code provided for a MIL disabled option.
But the confusion continues, is the dash lamp controlled by an ECU transistor switched earth via pin 10 or, as Steve has determined, by the ECU applying 12Vdc to pin 10? Some info on this here:
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
So I'm going to go with a thorough check of the lamp wiring and:
NEW_STYLE_MIL_CODE = 1
for the next build and see what happens.
Edited by davep on Saturday 9th August 10:45
Id of blown my MIL lamp up long ago if the ECU put 12 volts on the wrong side of the LED- so I can confirm, its 12 volts on one side, then the lamp, then the MIL input on the ECU. I gather from Mr Adams that the MIL lamp wiring was corrected by TVR on later cars when it was moved on the dash. Early cars the wiring is wrong.
blitzracing said:
The MIL lamp is switched to ground by the ECU- so you need 12 volts on one side of the warning lamp, and the MIL connection to the ECU
Mark,Thanks for confirming, I never questioned the polarity on pin 10 because I trusted TVR’s wiring that relies on the ECU outputting +12v to turn on the MIL.
Mark Adams said:
However you won't see the TVR one come on at all, because it isn't wired correctly. Lucas intended that the MIL lamp should have an ignition-switched live feed, and the ECU would earth the lamp to turn it on. However TVR supplied the lamp with an earth, believing that the ECU would supply 12 Volts to it.
Thanks for the link to Mark A post above from the "Warning Light Symbol Panel" thread. It certainly clarifies TVR Precat's have the polarity on the MIL the wrong way around.
As a result I pulled my dash out this evening and rewired the MIL to IGN +12v and hay presto my MIL is now working. Therefore the ECU does definitely supply a negative feed to turn on the MIL and TVR had it the wrong way around.
davep said:
On to the next action point on the list, sustained high rev's and over-fuelling at start-up; Steve I think Dan's given us a good lead in here:
Dave, danbourassa said:
There is never "simultaneous operation" although there IS a short period of double rate injector pulsing. During this time, there is no non-fuel interrupt, so each bank is fired every 2 sparks instead of every 4 sparks. This period of time can easily be changed. The 16-bit variable at $009D/9E is initialized to 192 decimal at power on. The 14CUX software double injects for this many sparks after start-up. This is equivalent to 48 engine revolutions and lasts about 3 seconds. If you want to reduce fuel a little quicker at start-up, you might want to try reducing this number. It is not in the data section but can be found under reInitVars in file reset.asm.
I’ve changed the doubleInjecterRate variable in reset.asm from $C0 down to $20 and unfortunately I didn’t notice any different when the engine fires from cold. It still idles at 1,800rpm for 6 seconds before dropping down to the target idle speed. We some how need to reduce the stepper motor opening before the engine starts like the code does when the engine is hot. When the engine is cold the stepper is at 100% but when above 85 deg C the stepper motor drops to 30% before firing and therefore no high revving. Another option would be to remove the idle mode delay.
It's a great sign we are investigate minor issues.
blitzracing said:
Steve- I don’t yet have a good 3.9 non cat map- Im running the stock Range Rover map at the moment but it runs lean progressively above 3500 rpm however so its not ideal, I just need to get around to tweaking it. Id be quite interested just to try your own modified map and see how it runs as the engine spec's are not that far apart.
MarkI’ve noticed the Lambda scale/resolution is different on R3652 to R2967/R2422 and therefore I’ve performed some back to back tests in the same conditions.
R2967 long term was typically –3 % odd +26% even where as R3652 was –2% odd 48% even. I switched between the two revisions several times and the general trend was the same. The previous day the even lambda doubled from +34% to +68%. I really don’t know if the lambda resolution has reduced or the base fuel calculations have changed and lambda trim is applying more correction.
I’ll copy map 2 tables and scalars from TVR400 / Lander Rover 3.9 (they are identical) into R3652 & R2967 plus map 5 from a Cat Chimmaera 400. Hopefully your long term trims will give us a better understanding of what is going on. I’ll email you the bin as I’m concerned if it's run blind someone may run out of Lambda trim without knowing. It would be good if you could also compare map 2 idle AFR as I was seeing a slight difference but at least that can be corrected with the CO trim screw.
Edited by stevesprint on Monday 11th August 21:18
stevesprint said:
Mark,
Are you being serious? Wouldn't that overload the motor and burn it out?
How about lowering the base idle?
Steve
Not at all- that buzz you hear as the engine is turned off is the stepper being pushed against the end stop- the ECU overdrives it by some margin to make sure its fully retracted. Adding a few washers just restricts its return path so you dont get as much air on start up- Ive got mine packed out by a about 3-4mm , works a treat.Are you being serious? Wouldn't that overload the motor and burn it out?
How about lowering the base idle?
Steve
blitzracing said:
Not at all- that buzz you hear as the engine is turned off is the stepper being pushed against the end stop- the ECU overdrives it by some margin to make sure its fully retracted. Adding a few washers just restricts its return path so you dont get as much air on start up- Ive got mine packed out by a about 3-4mm , works a treat.
Mark, That sounds an excellent solution, well done and thanks.
Dan,
As I was bored one evening I decided to load my ECU ready for the morning with a lower mysteryDownCounter from $50 $00 to $01 $00. Unfortunately I didn't notice any differences on the road, on RoverGauge or on the AFR gauge. The Lambda long term trims kicked in after the usual 2 mins and the overrun was inhibited for the first minute as usual.
As mysteryDownCounter is in the data section I assume it’s designed to be configurable, therefore I may try increasing it next time.
You can tell I’m running out of parameters to test before the winter.
Mark
I’ve merged the standard TVR 400 Precat and TVR 400 CAT into one prom with the MIL lamp enabled. The fuel & coolant tables, rpm limits etc are standard and exactly as per each vehicle including the traditional TVR overrun. As it’s based on the later TVR code the road speed limiter is also disabled correctly in the code and not in the data.
The only very slight difference you may notice is the idle speed at 800 rpm as there is only one common idle setting for all maps.
You can download it from
http://www.stevesprint.com/remap-14cux/bins/R2967_...
I'll do the same for R3652 next as I'm keen for you to compare the lambda trims and map 2 idle AFR.
I’ve merged the standard TVR 400 Precat and TVR 400 CAT into one prom with the MIL lamp enabled. The fuel & coolant tables, rpm limits etc are standard and exactly as per each vehicle including the traditional TVR overrun. As it’s based on the later TVR code the road speed limiter is also disabled correctly in the code and not in the data.
The only very slight difference you may notice is the idle speed at 800 rpm as there is only one common idle setting for all maps.
You can download it from
http://www.stevesprint.com/remap-14cux/bins/R2967_...
I'll do the same for R3652 next as I'm keen for you to compare the lambda trims and map 2 idle AFR.
Edited by stevesprint on Friday 15th August 19:44
Mark,
I've emailed you Land Rover R3652 but for TVR 400 CAT and non CAT as the 400 version is untested. However, I have been successfully running a R3652 430 Steve Sprint special version nearly everyday for the last 2 weeks without any driving issues or fault codes. In fact R3652 with the TVR overrun drives as well as R2967 including feathering the throttle in 3rd at 1,500 RPM. I never have to dip the clutch to stop shunting and it even passed the MOT emission test this week.
Although I've enabled the MIL in R2967_400 this later Land Rover version is even better as the MIL gives a reassuring flash each time the ignition is turned on. I've also removed the road speed limiter in the code as Dan has taught us, so it would be good if you could load a copy onto Lez's ECU, only joking.
I'm interested to hear how the lambda long term trims vary between R2967 and R3652 on your car as you know what to expect and I value your experienced opinion. Would it be normal for the long term trim to keep varying, with the same prom, between odd -7% to +1% and even +18% to +51%?
Ultimately before the winter I want to determine if the lambda trim ranges are different between revisions and work out if there is a configureable parameter in the data section to increase/decrease the lambda trim range.
None of this re-mapping would be possible without Dan's prom rebuild project that I'm now completely hooked on. It's much simpler and clearer than hacking the bins plus automatically fixes the checksum and duplicates the prom ready for burning. It's also easier to document and keep track of your various mods. Mark, if you are interested, in the winter we could have a pub session to help you get started, you could always start by trying to familiarise yourself with this data file
http://www.stevesprint.com/remap-14cux/bins/data_R...
There are loads of good text editors on the internet, I use TextPad as it's as simple as notepad and has a few extra features like file comparison and displays the current line and column number. I also use a file manager call Total Commander that has totally revolutionised my life.
With Dan's comments in his rebuild project we can change more than just the data and I'm sure you'll love it as much as I do.
I've emailed you Land Rover R3652 but for TVR 400 CAT and non CAT as the 400 version is untested. However, I have been successfully running a R3652 430 Steve Sprint special version nearly everyday for the last 2 weeks without any driving issues or fault codes. In fact R3652 with the TVR overrun drives as well as R2967 including feathering the throttle in 3rd at 1,500 RPM. I never have to dip the clutch to stop shunting and it even passed the MOT emission test this week.
Although I've enabled the MIL in R2967_400 this later Land Rover version is even better as the MIL gives a reassuring flash each time the ignition is turned on. I've also removed the road speed limiter in the code as Dan has taught us, so it would be good if you could load a copy onto Lez's ECU, only joking.
I'm interested to hear how the lambda long term trims vary between R2967 and R3652 on your car as you know what to expect and I value your experienced opinion. Would it be normal for the long term trim to keep varying, with the same prom, between odd -7% to +1% and even +18% to +51%?
Ultimately before the winter I want to determine if the lambda trim ranges are different between revisions and work out if there is a configureable parameter in the data section to increase/decrease the lambda trim range.
blitzracing said:
You are a fuel map god sir!
That must mean you're the hardware god who is always very generous with his time answering everyone's questions. None of this re-mapping would be possible without Dan's prom rebuild project that I'm now completely hooked on. It's much simpler and clearer than hacking the bins plus automatically fixes the checksum and duplicates the prom ready for burning. It's also easier to document and keep track of your various mods. Mark, if you are interested, in the winter we could have a pub session to help you get started, you could always start by trying to familiarise yourself with this data file
http://www.stevesprint.com/remap-14cux/bins/data_R...
There are loads of good text editors on the internet, I use TextPad as it's as simple as notepad and has a few extra features like file comparison and displays the current line and column number. I also use a file manager call Total Commander that has totally revolutionised my life.
With Dan's comments in his rebuild project we can change more than just the data and I'm sure you'll love it as much as I do.
Edited by stevesprint on Monday 18th August 00:06
Colin,
I know you like to be informed of any RoverGauge issues regards of however minor. Therefore I should mention in 0.7.2 the long trim meter bars remain in the short term position when the long term trims are zero. I’m sure you realise this only happens after an ECU reset and before the long term trims wake up. '0%' for long term is displayed correctly and the long term trim meter bars start working correctly once the long trim is non zero.
You can see from the screen shot I'm getting a lot of pleasure from your RoverGauge and your Fathers rebuild project. That's R3652 with the Chimmaera 450 CAT map and I've set the tune ID to 43 for 4.3litre and 09 for 09 overrun thershold.
I know you like to be informed of any RoverGauge issues regards of however minor. Therefore I should mention in 0.7.2 the long trim meter bars remain in the short term position when the long term trims are zero. I’m sure you realise this only happens after an ECU reset and before the long term trims wake up. '0%' for long term is displayed correctly and the long term trim meter bars start working correctly once the long trim is non zero.
You can see from the screen shot I'm getting a lot of pleasure from your RoverGauge and your Fathers rebuild project. That's R3652 with the Chimmaera 450 CAT map and I've set the tune ID to 43 for 4.3litre and 09 for 09 overrun thershold.
stevesprint said:
Colin,
I know you like to be informed of any RoverGauge issues regards of however minor. Therefore I should mention in 0.7.2 the long trim meter bars remain in the short term position when the long term trims are zero. I’m sure you realise this only happens after an ECU reset and before the long term trims wake up. '0%' for long term is displayed correctly and the long term trim meter bars start working correctly once the long trim is non zero.
Ah, this old thing. As far as I can tell, this is actually a bug in the Qt framework itself. The value of the bar does indeed update behind the scenes, but for some reason, it's not re-drawn on the display when the new value is small. I think I found that a value of 3 was the threshold.I know you like to be informed of any RoverGauge issues regards of however minor. Therefore I should mention in 0.7.2 the long trim meter bars remain in the short term position when the long term trims are zero. I’m sure you realise this only happens after an ECU reset and before the long term trims wake up. '0%' for long term is displayed correctly and the long term trim meter bars start working correctly once the long trim is non zero.
When RoverGauge was based on the old version the toolkit, Qt4, I had a workaround in my code to force a repaint for small values. When I switched to Qt5, I had thought that this bug was fixed as I wasn't able to reproduce it. It looks like it's still a problem, so I'll put the workaround back in and do another release at some point.
Hi Guys,
I've been reading this thread from the outside for months, finally joined up when I saw idle control discussions!
Mods if this is getting away from the topic can you split it please? Didn't want to fill the board up with lots of related threads unecessarily.
My own car has a 3.5 converted to serp and 14cux, currently with a 1992 3.9 Range Rover ECU. The idle control is not brilliant, when starting the engine fires then almost instantly dies. Second turn it fires and manages to gain control and the rpm is higher for a few seconds then drops down as per it should do. This is better when engine is warm, cold it can be a bit of a pest.
Questions are around
a) the ECU I am using, would a 3.5 one work better?
b) the 4lb lighter flywheel I have
c) something else I havent considered?
The engine is not long rebuilt, flowed heads, balanced, lightened flywheel, Piper270i cam, higher than standard compression. Base idle is set correctly, new plugs fitted. All sensors reading correctly and have been claibrated as per the manual.
Is there part of the coding that will allow stepper motor changes or is something else likely to be at fault?
Cheers
I've been reading this thread from the outside for months, finally joined up when I saw idle control discussions!
Mods if this is getting away from the topic can you split it please? Didn't want to fill the board up with lots of related threads unecessarily.
My own car has a 3.5 converted to serp and 14cux, currently with a 1992 3.9 Range Rover ECU. The idle control is not brilliant, when starting the engine fires then almost instantly dies. Second turn it fires and manages to gain control and the rpm is higher for a few seconds then drops down as per it should do. This is better when engine is warm, cold it can be a bit of a pest.
Questions are around
a) the ECU I am using, would a 3.5 one work better?
b) the 4lb lighter flywheel I have
c) something else I havent considered?
The engine is not long rebuilt, flowed heads, balanced, lightened flywheel, Piper270i cam, higher than standard compression. Base idle is set correctly, new plugs fitted. All sensors reading correctly and have been claibrated as per the manual.
Is there part of the coding that will allow stepper motor changes or is something else likely to be at fault?
Cheers
Welcome to the thread.
I don't think going to an earlier 3.5 ECU would be beneficial overall. It would probably have to be a 14CU (not the 14CUX) which is not fully compatible. I also don't think the lightened flywheel is part of the problem.
It would be helpful to know what tune version you are using since idle control is one of those things that continued to be tweaked and improved over the life of the 14CUX. Knowing the range used by the stepper motor would also be helpful. Also, I'm assuming that you have a hotwire MAF sensor and not the earlier style.
If it's just a startup problem and the vehicle runs fine after that, it may be that you're just not getting enough fuel at cold startup. If you have a spare temperature sensor (either coolant or fuel, it doesn't matter which) you may want to chill it in ice water and temporarily connect it in place of the coolant sensor and try starting the engine when cold. If this improves the startup, it will have proven this point.
I don't think going to an earlier 3.5 ECU would be beneficial overall. It would probably have to be a 14CU (not the 14CUX) which is not fully compatible. I also don't think the lightened flywheel is part of the problem.
It would be helpful to know what tune version you are using since idle control is one of those things that continued to be tweaked and improved over the life of the 14CUX. Knowing the range used by the stepper motor would also be helpful. Also, I'm assuming that you have a hotwire MAF sensor and not the earlier style.
If it's just a startup problem and the vehicle runs fine after that, it may be that you're just not getting enough fuel at cold startup. If you have a spare temperature sensor (either coolant or fuel, it doesn't matter which) you may want to chill it in ice water and temporarily connect it in place of the coolant sensor and try starting the engine when cold. If this improves the startup, it will have proven this point.
Hi Dan,
The Land Rover Discovery used a 3.5 14CUX engine for a short while so I intend to get a look at the map in that chip ASAP.
Its a 5AM AFM and the temp sensor is new genuine Land Rover. Its better when hot but not completely gone so your suggestoin of lack of fuelling sounds Very possible. I will get a screen shot of the map taken and post it up. It is an early ECU in that it was pre serp so definitely won’t have the upgrades of a late car in terms of idle control.
cheers
The Land Rover Discovery used a 3.5 14CUX engine for a short while so I intend to get a look at the map in that chip ASAP.
Its a 5AM AFM and the temp sensor is new genuine Land Rover. Its better when hot but not completely gone so your suggestoin of lack of fuelling sounds Very possible. I will get a screen shot of the map taken and post it up. It is an early ECU in that it was pre serp so definitely won’t have the upgrades of a late car in terms of idle control.
cheers
rangerovering said:
The Land Rover Discovery used a 3.5 14CUX engine for a short while so I intend to get a look at the map in that chip ASAP.
I wasn't aware of this and I would love a copy of the binary when you get it.rangerovering said:
Its a 5AM AFM and the temp sensor is new genuine Land Rover.
I wasn't suggesting that the temp sensor was bad. Chilling it is just a convenient way to enrich the mixture for trouble shooting purposes.Keep us posted on your progress.
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