mickeyw Posted October 31, 2016 Share Posted October 31, 2016 I recently acquired a V8 ECU. It's badged Land Rover, PRC6999 and date coded 0189, which makes it IMO an early 3.9 unit. My plan for this unit is as a test bed for fitting a socket for the tuning chip. I appreciate this is not an easy task, hence practicing on a unit I am not currently dependent on. My reason for this mod is so I can program a chip with the correct R map for a 4.2 that's lurking in my shed. I opened this up, and am now a little puzzled. The innards don't look like any 14CUX I have seen before, socketed or non-socketed. I know the flapper 3.5 ECUs look very different in their silver boxes, so obviously it's not for one of those. The tune map number R1828 doesn't correspond with any listed on Steve Sprint's site either. There is also a mystery label 'Gammel ECU' on the outside, but this means nothing to me or popular search engines. Can any of our resident V8 oracles shed any light on what spec this item actually is? TIA Quote Link to comment Share on other sites More sharing options...
zardos Posted October 31, 2016 Share Posted October 31, 2016 I think Gammel translates from various languages (Danish, Norwegian,.. ) as "Old"https://en.wiktionary.org/wiki/gammel 1 Quote Link to comment Share on other sites More sharing options...
elbekko Posted October 31, 2016 Share Posted October 31, 2016 The part number should say enough: http://www.ebay.com/itm/Land-Rover-Range-Rover-Classic-ECU-14CU-PRC6999-1989-RRC-/252154212391 Together with the date code, which is probably somewhere in 1989. Quote Link to comment Share on other sites More sharing options...
mickeyw Posted October 31, 2016 Author Share Posted October 31, 2016 1 hour ago, elbekko said: The part number should say enough: http://www.ebay.com/itm/Land-Rover-Range-Rover-Classic-ECU-14CU-PRC6999-1989-RRC-/252154212391 Together with the date code, which is probably somewhere in 1989. Well therein lies some confusion. Depending where you look, some resources refer to PRC6999 as a 14 CUX, and others as a 14CU. One constant is that they all state 3.9 fitment. Agreed on the date code - Jan (month 1) 1989. I don't know what the difference is between the two, other than the 14CUX superceding the 14CU. The plug appears to be the same, but the PCB clearly isn't. Are they interchangeable? Presumably the later version has features its predecessor doesn't??? Quote Link to comment Share on other sites More sharing options...
zardos Posted October 31, 2016 Share Posted October 31, 2016 84913A is the Manufacturer part number there was an 84913 for the same vehicle (May be the A means amened?) Differences in this number can mean just an updated fuel map was factory loaded Quote Link to comment Share on other sites More sharing options...
SteveSprint Posted January 22, 2018 Share Posted January 22, 2018 (edited) mickeyw I’ve just spotted this thread and if you are still interested I can confirm your PRC6999 ECU dated 0189 in the picture is a 14CU and not a 14CUX, it doesn’t have the 14CUX’s MVA5033(KA) square chip and therefore the tune chips are not compatible. 14CUXs manufactured in the first year of production have the MVA5033 chip and all later 14CUXs have the MVA5033KA chip. The MVA5033(KA) chip contains extra “Random Access Memory” and the interface to the OBD fault code display plus some extra functions that go over my head. From a Land Rover Manual 13CU (1987-88) 14CU (1989) 14CUX (1990-95) Have you tried connecting RoverGauge? The 14CU use the same pins 9 and 18 for the serial port but I doubt all the diagnostics would display correctly as the 14CU doesn’t have 5 maps like the 14CUX. I live in hope RoverGauge connects just to download a copy of the tune map as I’m very interested to investigate the differences between the 14CU and 14CUX in more detail. Cheers SteveSprint Edited January 22, 2018 by SteveSprint Additional information Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 23, 2018 Share Posted January 23, 2018 If the map is in an EEPROM fire up a raspberry Pi and dump the whole lot out. Would be interesting to see some dumps of factory fuel (and later ignition) maps. Quote Link to comment Share on other sites More sharing options...
mickeyw Posted January 23, 2018 Author Share Posted January 23, 2018 16 hours ago, SteveSprint said: mickeyw I’ve just spotted this thread and if you are still interested I can confirm your PRC6999 ECU dated 0189 in the picture is a 14CU and not a 14CUX, it doesn’t have the 14CUX’s MVA5033(KA) square chip and therefore the tune chips are not compatible. 14CUXs manufactured in the first year of production have the MVA5033 chip and all later 14CUXs have the MVA5033KA chip. The MVA5033(KA) chip contains extra “Random Access Memory” and the interface to the OBD fault code display plus some extra functions that go over my head. From a Land Rover Manual 13CU (1987-88) 14CU (1989) 14CUX (1990-95) Have you tried connecting RoverGauge? The 14CU use the same pins 9 and 18 for the serial port but I doubt all the diagnostics would display correctly as the 14CU doesn’t have 5 maps like the 14CUX. I live in hope RoverGauge connects just to download a copy of the tune map as I’m very interested to investigate the differences between the 14CU and 14CUX in more detail. Cheers SteveSprint Welcome Steve, and fancy you finding this here And thanks for waking up a pretty old thread with some good info. As with so many projects in my life, not very much has happened with this. I do have RoverGauge, and have had it plugged in to various other ECUs that have been in my 110. My original reason for acquiring the ECU was for a practice run installing a chip socket, yet evidently the 14CU is no good for that purpose. Do you reckon I can plug it in in place of the 14CUX for the purpose of reading the map, without starting the engine of course? Fridge the 14CUX only uses a PROM, so guessing your idea wouldn't work - not that I'd have a clue how to go about that Steve, my original plan was to install a socket, and program a chip with the factory fuel map for the 4.2, as the chances of finding a 4.2 ECU seem quite slim. I run non-cat, and the idea was to run R3116. R3384 says it's UK Range Rover 4.2 1995>, so assuming that is a cat map. Need to obtain and learn how to use a suitable programmer first though. Currently I'm running a yellow 910 Ohm tune resistor (which says it's for a 4.2), I must check what the ECU part number (not sure if it's ex RR or Disco) and tune map numbers are. It's been a while since I looked at things. The first ECU I ran was hopelessly rich, but the current one is not too bad...well it passed an MOT anyway... The LR is a 1986, so emissions allowance is fairly generous. I'll post up some more info later when I've had a chance to refresh my memory. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted January 23, 2018 Share Posted January 23, 2018 1 hour ago, mickeyw said: Fridge the 14CUX only uses a PROM, so guessing your idea wouldn't work Why not? There's only ever been one write-only memory chip, most of the others you can read from otherwise they're not terribly useful If you don't want to use a Pi you could always grab some toggle-switches and pen + paper and do it old-school Edit: Never mind, just found Steve's website and realised he's dumped loads of bins out of ECU's. Would really love to see ignition maps for the later (P38 / D2) ones though, hint hint Quote Link to comment Share on other sites More sharing options...
Disco-Ron Posted January 23, 2018 Share Posted January 23, 2018 Excuse my ignorance.... but don't flapper ecus have 2 rows of connectors... and hotwire 3.....?. Quote Link to comment Share on other sites More sharing options...
mickeyw Posted January 23, 2018 Author Share Posted January 23, 2018 1 hour ago, FridgeFreezer said: Why not? There's only ever been one write-only memory chip, most of the others you can read from otherwise they're not terribly useful I've no idea Jon. I bow to your superior knowledge of electrickery. I was just guessing 😁 Quote Link to comment Share on other sites More sharing options...
elbekko Posted January 24, 2018 Share Posted January 24, 2018 13 hours ago, FridgeFreezer said: Would really love to see ignition maps for the later (P38 / D2) ones though, hint hint Ditto. I've tried to find all sorts of Motronic tuning software, but haven't succeeded. Quote Link to comment Share on other sites More sharing options...
mickeyw Posted January 24, 2018 Author Share Posted January 24, 2018 OK,so ECUs dabbled with so far, plus some screen grabs from RoverGauge 1. PRC9611 dated 0499. This one ran terribly rich. Runs R2666 2. PRC9611 dated 1592. This one just doesn't run happily.Also runs R2666 3. AMR3242 dated 3394. This is what I am currently running and has R3383. I haven 't been able to plug the 14CU in. It seems to be hiding from me somewhere in the garage. I'll keep an eye open though. So according to Steve's data, these are all 3.9 maps from different periods. The last one (that I'm running) came from a serpentine engined (cat equipped) Discovery. It's also the only one the engine seems to run reasonably well on, and isn't running stinking rich. Being a 3.9 map I daresay the engine would go even better with the correct tune. You'll notice I've adjusted the MAF CO trim to compensate for a lack of cat. Also note that all engine and fuel temp sensors have been checked at cold and hot, and fall within LR book readings. So this leads me to wonder which ECUs contain a 4.2 map for it to be selected, other of course than one originating from a RR LSE. Steve, given I'm running without cats, ought I to run R3361 or the later R3384? Any guidance would be appreciated. Quote Link to comment Share on other sites More sharing options...
SteveSprint Posted January 28, 2018 Share Posted January 28, 2018 Mickey Thanks for the welcome. On further investigation it appears the 14CU and 14CUX main connection pin layouts are the same except for the serial port ground, see pages 101 and 102 http://www.remap-14cux.uk/14cux-docs/1314CU_14CUX_Systems.pdf . The 14CU had a separate serial ground wire on pin 37 that was later combined on the 14CUX’s ground on pin 27, therefore you would have to ground pin 37 in the 14CUX loom. The 14CUX serial port ground is highlighted in this diagram http://www.remap-14cux.uk/14cux-docs/14CUX_diagram_1993.pdf . If RoverGauge did successfully connect to a 14CU it wouldn’t show the fuel table correctly as RoverGauge is designed for the 14CUX prom layout with the 5 fuel maps, where as the 14CU only has one fuel map. However I still live in hope 14CU serial port would connect to RoverGauge and read/save the prom chip but there is no guarantee it would work. The only other way to read the prom chip would be to cut out the chip and solder the legs back on. I’m personally interested to see a 14CU prom file especially to see if the 14CUX map 0 (limp home map) has the data structure as the 14CU’s single map, sorry I don’t get out enough in the winter. I’ve also just noticed the 14CU & 14CUX injectors are mechanically different but electrically and the flow rates are very similar, see page 68 http://www.remap-14cux.uk/14cux-docs/LR_Fuel_InjectionSystems.pdf You are always welcome to help yourself to the tune chip files here http://www.remap-14cux.uk/bins/ where you’ll see I have three 4.2 tune files to choose from, however as you’re running a non cat map (3) without cats I suggest R3116 as it the only 4.2 chip file that actually has the 4.2 fuel table in the non cat maps 1,2 & 3, where as R3361 & R3834 non cat maps contain 3.9 fuel table and data. To quickly identify the fuel tables in each map see the “Map” and “Main Fuel Scalars” rows in this table http://remap-14cux.uk/LR-TVR-settings.html . I would be happy to add any additional maps if you have any. I’m sure you realise the main advantage running the non cat maps is you can remap for the following AFRs 15.5:1 Motorway cruise 13.5:1 Smooth idle 12.7:1 full load/max power Fridge Sorry I don’t have any GEMS ignition maps, I’m sure you know GEMS has knock sensors and the fuel and ignition is self mapping, however here's a good guide for TVR ignition timing https://www.pistonheads.com/gassing/topic.asp?t=828064 Cheers SteveSprint Quote Link to comment Share on other sites More sharing options...
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